Search

Peroxisome proliferator-activated receptors (PPARs) are important targets for cannabidiol (CBD), which mediate many of its biological actions. The hypothesis of the present research assumed that PPARs affect the gut response to different challenge factors in chickens (C. perfringens vs. lipopolysaccharides (LPS) from E. coli), and that CBD can mediate the pathways of this response. The study proved that CBD and the challenge factors significantly affect the expression level of PPARα (p = 0.001) and selected genes determining gut barrier function. A positive correlation was demonstrated between PPARs and genes involved in the formation of tight junctions, immune, and oxidative stress responses in chickens. Dietary supplementation with CBD actively mediated the expression rate of PPARs, but the mechanism of interaction between CBD and PPARs was different depending on the stress factor used. The addition of CBD to the birds' diets did not contribute to reducing intestinal permeability under induced stress conditions nor cause stress, as indicated by the absence of elevated blood cortisol and endotoxin levels. CBD also supported the mechanisms of protecting intestinal cells from the cytotoxic effects in a C. perfringens challenge through the levels of genes involved in oxidative stress. This study indicates the importance of research toward understanding the mechanisms of PPARs as a target for enhancing intestinal barrier function, provides new results on the biological action of CBD in chickens, and shows a constant PPAR association with the jejunum mucosa of birds. [ABSTRACT FROM AUTHOR]

Simple Summary: Long photoperiods are commonly used in modern intensive broiler chicken farming, which are crucial environmental factors in the growth and health of broilers. Through different photoperiods experiments, we found that extending the photoperiods could promote the growth rate of broilers while reducing the feed efficiency, inhibiting acetylcholine and its relative-acetylcholine receptor expression, and inducing glucose metabolism disorders in broilers. In addition, these findings have important implications for future research on the role of glucose metabolism, acetylcholine, and its relative acetylcholine receptors in regulating the health of broilers underlying extending the photoperiods. Photoperiods are crucial environmental factors in the growth and health of modern intensive broiler chicken production. To date, the effects of different photoperiods on glucose metabolism, acetylcholine (ACh), and its relative acetylcholine receptor modulation in broilers remain elusive. Herein, we aimed to identify the effects of different photoperiods on regulating glucose metabolism, ACh, nicotinic acetylcholine receptor alpha 4 (α4 nAChR) mRNA, and M3 muscarinic acetylcholine receptor (M3 mAChR) modulation in broilers. A total of 216 healthy 5-day-old Arbor Acres (AA) male broilers was randomly assigned to 12L:12D, 18L:6D, and 24L:0D photoperiods for 4 weeks. The results show that, compared with the 12L:12D photoperiod, the 18L:6D and 24L:0D photoperiods significantly increase the average daily gain (ADG) and average daily feed intake (ADFI) of broilers (p < 0.05). However, the feed efficiency (FE) of broilers significantly decreased in the 18L:6D and 24L:0D photoperiods (p < 0.05). Moreover, compared with the 12L:12D photoperiod, the ACh concentrations and α4 nAChR mRNA expression levels in the hypothalamus and medulla oblongata of broilers significantly increased (p < 0.05); M3 mAChR mRNA expression levels in cecum significantly reduced in the 18L:6D photoperiod and the 24L:0D photoperiod (p < 0.05). Compared with the 12L:12D photoperiod, the serum glucose (GLU), serum insulin (INS), serum triglyceride (TG) levels, and homeostasis model assessment of insulin resistance (HOMA-IR) of broilers significantly enhanced in the 18L:6D and 24L:0D photoperiods (p < 0.05). Our results indicate that extending the photoperiod can promote the growth rate, ACh expression, and α4 nAChR mRNA expression of broilers while reducing the feed efficiency, inhibiting M3 mAChR mRNA expression, and inducing glucose metabolism disorders in broilers. [ABSTRACT FROM AUTHOR]

Simple Summary: This present study evaluated the efficacy of dietary benzoic acid (BA) and oregano essential oil (OEO) separately or together as a substitute for a commercial coccidiostatic drug (salinomycin) on growth performance and physiological and immunological responses in broiler chickens challenged with Eimeria species. It was found that the BA and OEO applied alone or in combination significantly reduced gut pathogenic bacteria (Salmonella and Escherichia coli) and Eimeria spp. and concurrently enhanced the Lactobacillus population with better body weight gain, improved feed utilization, and superior hematological values. It boosted the immune system by enhancing Eimeria-specific immunoglobulin Y titer and up- and down-regulated various immune gene expressions to protect the chickens from inflammatory reactions that were not demonstrated in salinomycin-treated birds. This study suggests that the combined application of OEO and BA can substitute for salinomycin in controlling coccidiosis as well as improving growth performance, gut health, and immune responses in broiler chickens. To overcome the antimicrobial residues in food, benzoic acid (BA) and oregano essential oil (OEO) are used in the broiler chicken industry. Independently, both exerted anticoccidial and antimicrobial actions and improved growth performance in broiler chickens. Their effect may be multiplied when they are used in combination. This present study was carried out to evaluate the efficacy of dietary BA and OEO alone or in combination as a substitute for a commercial coccidiostatic drug on growth performance and physiological and immunological responses in broiler chickens challenged with Eimeria species. A total of 252 unsexed 1-day-old broiler chicks were equally allotted to 36 pens, each pen containing seven chicks. The pens were randomly assigned to six treatments with six pens (replicates) for each treatment (n = 6)—(i) negative control, (ii) positive control, coccidia-challenged and non-treated, (iii) supplemented with salinomycin (an anti-coccidial drug) at 60 mg/kg of feed and coccidia-challenged, (iv) supplemented with BA at 500 mg/kg of feed and coccidia-challenged, (v) supplemented with OEOat 500 mg/kg of feed and coccidia-challenged (OEO), and (vi) supplemented with BA at 500 mg/kg of feed and OEO at 500 mg/kg of feed and coccidia-challenged (B&O). The liver enzymes and thyroxine and creatinine levels were not affected (p > 0.05) both in coccidia-challenged and supplemented chickens. The BA and OEO applied separately or in combination (B&O) significantly (p < 0.05) reduced gut pathogenic bacteria (Salmonella and Escherichia coli) and Eimeria spp., and concurrently enhanced (p > 0.05) the Lactobacillus population with better body weight gain, improved feed utilization, and superior hematological values. It also up-regulated (p > 0.05) the interferon-γ gene expression and down-regulated (p < 0.05) the interleukin-10 and Toll-like receptor-4 gene expression to protect the chickens from inflammatory reactions, which were not demonstrated in salinomycin-treated birds. The B&O supplementation increased (p < 0.05) the immune system by enhancing Eimeria-specific immunoglobulin Y titer and lymphocyte proliferation response. This study suggests that the combined application of OEO and BA can substitute for a commercial anti-coccidial agent (salinomycin) in controlling coccidiosis as well as improving growth performance, gut health, and immune responses in broiler chickens with a means of antimicrobial-resistant free food products. [ABSTRACT FROM AUTHOR]

Simple Summary: Coccidiosis affects broiler chickens, causing economic losses since infected chickens grow less efficiently than healthy birds. Coccidiosis is caused by a parasite Eimeria that infects the gastrointestinal tract. In the current study, changes in the bacteria of the jejunum and ileum following infection with Eimeria maxima were determined. Samples were taken between 0 and 14 days post-infection. The infection resulted in decreased body weight gain, increased feed conversion ratio, compromised gut morphology, and decreased plasma carotenoid levels. Microbiota composition was determined by sequencing a portion of the 16s rDNA gene. The results indicate that infection affected the diversity within and between bacterial communities, particularly at the height of infection. In samples from infected birds, species of bacteria that can be opportunistic pathogens were more abundant than in healthy birds. In uninfected birds, bacteria that produce short-chain fatty acids and are associated with improved growth were more abundant. Eimeria maxima affects the ecology of the small intestine by disrupting its integrity and changes the types of bacteria present to those that could be opportunistic pathogens. Coccidiosis is a complex gastrointestinal disease, and understanding its effects on the host will help find effective control methods in the future. Coccidiosis in broiler chickens continues to be a major disease of the gastrointestinal tract, causing economic losses to the poultry industry worldwide. The goal of this study was to generate a symptomatic Eimeria maxima (1000 oocysts) infection to determine its effect on the luminal and mucosal microbiota populations (L and M) in the jejunum and ileum (J and IL). Samples were taken from day 0 to 14 post-infection, and sequencing of 16S rRNA was performed using Illumina technology. Infected birds had significantly (p < 0.0001) lower body weight gain (BWG), higher feed conversion ratio (FCR) (p = 0.0015), increased crypt depth, and decreased villus height (p < 0.05). The significant differences in alpha and beta diversity were observed primarily at height of infection (D7). Analysis of taxonomy indicated that J-L and M were dominated by Lactobacillus, and in IL-M, changeover from Candidatus Arthromitus to Lactobacillus as the major taxon was observed, which occurred quicky in infected animals. LEfSe analysis found that in the J-M of infected chickens, Lactobacillus was significantly more abundant in infected (IF) chickens. These findings show that E. maxima infection affects the microbiota of the small intestine in a time-dependent manner, with different effects on the luminal and mucosal populations. [ABSTRACT FROM AUTHOR]

Simple Summary: Transcriptomic studies allow us to reveal at the molecular level the nature of the influence of various paratypical factors on physiological processes underlying the formation of animal productivity and health. The uncontrolled use of feed antibiotics is one of the key reasons for the development of antibiotic resistance in pathogens, necessitating the testing of alternative nutraceuticals in animal nutrition, including phytobiotics, the effectiveness and biological properties of which can be identified with the help of modern molecular genetic biotechnologies in addition to traditional methods of phenotype assessment. The nature of changes in gene expression related to the formation of skeletal muscles and lipogenesis was studied when using biologically active substances extracted from plants in the nutrition of broiler chickens. The study aimed to analyze gene expression linked to skeletal muscle growth and lipid metabolism in broiler chickens fed with plant extracts. Five groups of chickens were formed: four experimental groups and one control group. The diets of the experimental groups were supplemented with different plant extracts: chicory, St. John's wort, maral root, and creeping thyme, whereas the control group received feed without phytobiotic compounds. Weekly weighings were conducted (n = 36). The chickens were slaughtered at day 26 for tissue sampling of four birds from each group. Gene expression (MYOG, MSTN, FASN) related to muscle growth and fatty acid synthesis was analyzed using the β-actin ACTB gene as a reference. Blood samples were taken at day 35 for biochemical analysis and anatomical dissection was performed. The study revealed that using plant extracts from chicory, thyme, and maral root increased MYOG gene activity by 4.21, 7.45, and 8.93 times, respectively. T. serpyllum extract boosted the MSTN gene by 10.93 times, impacting muscle growth regulation. FASN gene expression for fatty acid synthesis increased significantly by 18.22–184.12 times with plant extracts. The best results regarding meat productivity of chickens were obtained when using R. carthamoides extract. The results of the study will serve as a basis for further development of a phytocomposition designed to increase the meat productivity of broiler chickens in the production of environmentally safe poultry products. [ABSTRACT FROM AUTHOR]

Escherichia coli isolates from intensive poultry production are associated with antimicrobial resistance and worldwide health problems. The aim of the study was to detect and evaluate the phenotypic and genotypic antimicrobial resistance, biofilm formation, phylogenetic typing, and virulence factors in E. coli isolates from the rectal swabs of chickens from two farms and swabs of chicken meat purchased from Slovakian food markets. Interpretative readings of minimal inhibitory concentration (MIC) revealed dominant resistance to ampicillin (>50%) in both groups. We also detected higher resistance to ciprofloxacin (45%), tetracycline, ampicillin + sulbactam, and trimethoprim + sulfonamide (each >30%). Here, 28.57% of the strains studied were multidrug-resistant (MDR). The formation of weak biofilms was confirmed in 8.8% of E. coli, while one of the strains obtained from chicken cloacal swabs was classified as a strong biofilm producer. The most frequently confirmed phylogenetic groups in E. coli were B1 and A1 in all groups. PCR detection revealed the presence of genes encoding tetracycline resistance (tetAB) and plasmid-mediated quinolone resistance (qnrABS), and Int1 (52.9%), Tn3 (76.5%), kpsMT II (8.8%), fimA (97.1%), cvaC (38.2%), and iutA (76.5%) genes in the strains studied. Our results demonstrate that chickens and chicken meat were the source of antibiotic-resistant, biofilm-forming, and virulent E. coli, representing a potential risk from the point of view of the One Health concept. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examines the impact of replacing 50% of soybean meal (SBM) with untreated cottonseed meal (CSM), fermented CSM (FCSM), or electron beam-irradiated CSM (ICSM) on the growth performance and physiological characteristics of broiler chickens. The findings revealed that broilers fed ICSM achieved higher body weight than those fed CSM. Furthermore, substituting 50% of SBM with FCSM significantly improved growth performance and nutrient digestibility compared to CSM and ICSM diets. In addition, including FCSM in the diet enhanced digestive enzyme activity, balanced the microbiota population, and reduced ammonia emissions compared to other experimental diets. Overall, FCSM provided superior nutritional benefits compared to both untreated and irradiated CSM in broiler diets. Therefore, FCSM can be used as a suitable alternative to SBM in broiler chicken diets. This study was conducted to investigate and compare the effects of substituting soybean meal (SBM) with untreated cottonseed meal (CSM), fermented CSM (FCSM), or electron beam-irradiated CSM (ICSM) on the growth performance, cecal microbiota, digestive enzyme activity, apparent ileal digestibility (AID), and excreta gas emission of broiler chickens. A total of 384 one-day-old male broiler chickens were randomly assigned to four experimental diets, with eight replicates per diet and 12 birds per replicate, for six weeks. The experimental diets consisted of a control diet based on corn–SBM and three other diets in which 50% of the SBM (control) was substituted with CSM in its raw, irradiated, and fermented forms. The results showed that throughout the entire rearing period, feeding broiler chickens with ICSM significantly increased average daily gain (ADG) and body weight (BW) compared to the CSM diet (p < 0.05). Replacing 50% of SBM with FCSM led to a significant improvement in BW, ADG, and feed conversion ratio (FCR) compared to the CSM and ICSM diets (p < 0.05). Interestingly, no significant differences in BW, ADG, or FCR were observed between birds fed FCSM and those on the control diet (p > 0.05). Birds fed FCSM diets exhibited the lowest pH value in the crop, ileum, and ceca. Substituting SBM with FCSM significantly reduced Escherichia coli and Clostridium spp. counts in the ceca, while enhancing the presence of Lactobacillus spp. (p < 0.05). The AID of protein and ether extract was higher in the FCSM group than in the CSM and ICSM groups (p < 0.05). Compared to the CSM diet, ICSM feeding improved protein digestibility (p < 0.05). Broiler chickens on the FCSM diet exhibited higher intestinal amylase and protease activity than those on the other diets (p < 0.05). Furthermore, feeding diets containing FCSM significantly reduced ammonia emissions compared to the other diets (p < 0.05). Overall, our results indicated that microbial fermentation of CSM is a more effective approach than irradiation for enhancing the nutritional value of CSM. Therefore, FCSM is recommended as a viable alternative protein source that can safely replace up to 50% of SBM in broiler chicken diets, particularly during times of fluctuating SBM prices and availability issues. [ABSTRACT FROM AUTHOR]

Amaranthus hypochondriacus is rich in nutrients and represents a feed resource with significant potential. This experiment aimed to study the effects of different proportions of Amaranthus hypochondriacus stem and leaf powder (AHSL) on intestinal digestive enzyme activities, cecal volatile fatty acids, and the microbiota of broilers. A total of 288 one-day-old male broilers (Ross 308) were randomly assigned to the control diet group and the 3%, 6%, and 9% AHSL diet group for days 0–21. Subsequently, the 3%, 6%, and 9% AHSL diets were switched to 5%, 10%, and 15% AHSL diets for days 22–42. The results demonstrated that the dietary inclusion of AHSL significantly affected sucrase activity in the jejunal mucosa (p < 0.05). The 5% AHSL group exhibited the highest sucrase activity, followed by the control group, both of which showed significantly higher activity compared to the 10% and 15% AHSL groups (p < 0.05). The cecal pH in the 5%, 10%, and 15% AHSL groups was significantly lower than that in the control group (p < 0.05). The contents of acetate, propionate, butyrate, and valerate in the cecum of the 10% and 15% AHSL groups were significantly higher than those of the control group (p < 0.05). The addition of AHSL had no significant effect on the alpha diversity of cecum microorganisms. The relative abundance of Ruminococcaceae_UCG_005 and Lactonifactor was significantly higher in the 10% AHSL group compared to the control group, whereas the 15% AHSL group had a significantly higher relative abundance of Clostridium_sensus_tricto12, Peptoclostridium, Anaerofilum, and Peptococcaceae. In summary, the inclusion of 5% AHSL in the diet enhances sucrase activity in the jejunum of broilers, while 10% or 15% AHSL increases the volatile fatty acid content and reduces the pH value in the cecum, without adverse effects on the cecal microbiota. [ABSTRACT FROM AUTHOR]

Objective: Multidrug-resistant, highly pathogenic Escherichia coli strains are the primary causative agents of intestinal and extraintestinal human diseases. The extensive utilization of antibiotics for farm animals has been identified as a contributing factor to the emergence and dissemination of E. coli strains that exhibit multidrug resistance and possess high pathogenic potential. Consequently, a significant research objective is to examine the genetic diversity of pathogenic E. coli strains and to identify those that may pose a threat to human health. Methods: In this study, we present the results of genome sequencing and analysis, as well as the physiological characterization of E. coli strain APEC 36, which was isolated from the liver of a broiler chicken with generalized colibacillosis. Results: We found that APEC 36 possess a number of mechanisms of antibiotic resistance, including antibiotic efflux, antibiotic inactivation, and antibiotic target alteration/replacement/protection. The most widely represented group among these mechanisms was that of antibiotic efflux. This finding is consistent with the strain's documented resistance to multiple antibiotics. APEC 36 has an extremely rare variant of the beta-lactamase CTX-M-169. Notwithstanding the multitude of systems for interfering with foreign DNA present in the strain, seven plasmids have been identified, three of which may possess novel replication origins. Additionally, qnrS1, which confers resistance to fluoroquinolones, was found to be encoded in the genome rather than in the plasmid. This suggests that the determinants of antibiotic resistance may be captured in the genome and stably transmitted from generation to generation. Conclusions: The APEC 36 strain has genes for toxins, adhesins, protectins, and an iron uptake system. The obtained set of genetic and physiological characteristics allowed us to assume that this strain has a high pathogenic potential for humans. [ABSTRACT FROM AUTHOR]

Simple Summary: The study evaluated the effects of Rumex nepalensis leaf powder (RNL) as a natural feed additive in broiler chickens. RNL @ 10 g/kg diet improved the body weight gain and feed conversion ratio of broilers. Total serum cholesterol was decreased when RNL was added @ 5 and 10 g/kg diet. Immunity of birds was better as depicted by increase in the serum levels of immunoglobulin G and immunoglobulin M levels in RNL supplemented groups. RNL @ 10 g/kg diet was found effective in enhancing the antioxidant enzyme status of birds in terms of increased serum superoxide dismutase and decreased malondialdehyde levels. Gut health of broilers improved by RNL as recorded by favorable results in cecal microbiology and intestinal histomorphology. Thus, RNL is a promising natural feed additive for improving the growth, immuno-antioxidant status and gut health of broiler chicken. The study investigated the impact of utilizing Rumex nepalensis leaf powder (RNL) as a phytogenic feed additive on performance, blood markers, intestinal microbiology and histomorphology in broiler chicken. One hundred eighty day-old Cobb broiler chicks were randomly divided into four treatment groups having three replicates with fifteen birds each. Four iso-caloric and iso-nitrogenous diets primarily based on maize–soybean were formulated, viz., CN (Control)—fed basal diet only; RNL2.5 (basal diet + 2.5 g/kg RNL); RNL5 (basal diet + 5 g/kg RNL); and RNL10 (basal diet + 10 g/kg RNL). The results revealed a significant (p < 0.05) increase in body weight gain and feed conversion ratio in dietary treatments compared to CN with best values in RNL10 followed by RNL5. The blood markers like glucose, total protein, creatinine, alanine transaminase (ALT) and aspartate transaminase (AST) showed no significance (p > 0.05) among all the treatments, however total cholesterol significantly (p < 0.05) decreased in RNL5 and RNL10 as against CN. Regarding immune parameters, immunoglobulin G (IgG) and immunoglobulin M (IgM) levels significantly (p < 0.05) enhanced in RNL5 and RNL10. Antioxidant enzyme status showed that superoxide dismutase (SOD) increased and malondialdehyde (MDA) decreased significantly (p < 0.05) in RNL10 compared to CN. Gut health in terms of cecal microbiology and histomorphology of duodenum and jejunum were altered by inclusion of RNL in the broiler diet. A significant decrease (p < 0.05) in coliform count was recorded by incorporation of dietary treatments with highest reduction in RNL10. Lactobacillus count and total viable count did not vary significantly (p > 0.05) among dietary treatments and CN. Duodenal and jejunal villus height and villus height/crypt depth ratio were significantly (p < 0.05) increased in RNL5 and RNL10 compared to RNL2.5 and CN. Thus, it could be concluded that inclusion of Rumex nepalensis leaf powder in the diet resulted in improved performance and better immuno-antioxidant status of broilers. Further, an improvement in the gut health was observed in terms of positive effects on cecal microbiota and intestinal histomorphology of broiler chickens. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the protective effects of xylooligosaccharide (XOS) on the growth performance and intestinal health of broilers challenged by avian pathogenic Escherichia coli (APEC). A total of 144 newly hatched male Lingnan yellow-feathered broilers were randomly divided into three groups (six replicates/group): a control (CON) group, an APEC group and an XOS group (APEC-challenged broilers supplemented with 1600 mg/kg XOS). Birds in the APEC and XOS groups were orally challenged with APEC from 7 to 12 d of age. Growth performance and intestinal health-related parameters were determined on d 13 and 17. The reductions (p < 0.05) in final body weight, average daily gain and elevation (p < 0.05) in intestinal APEC colonization in challenged broilers were counteracted by the XOS addition, which also alleviated the APEC-induced reductions (p < 0.05) in jejunal goblet cell count and density in broilers on d 17. Supplementing with XOS increased (p < 0.05) jejunal villus height and crypt depth, coupled with occludin and zonula occluden-1 expression, on d 17, and diminished the change (p < 0.05) in the jejunal inflammatory cytokine expression profile in a time-dependent manner. Moreover, cecal counts of total bacteria and Lactobacillus in challenged broilers were augmented (p < 0.05) by the XOS addition, which also mitigated APEC-induced reductions (p < 0.05) in cecal acetate, butyrate and valerate concentrations in broilers on d 13 or 17. Supplementing with XOS blocked the increases (p < 0.05) in the expression of cecal E. coli virulence genes relA and ompR on d 13 along with the expression of fimH and csgA on d 17. XOS alleviated APEC-induced growth retardation and intestinal disruption in broilers partially by restraining the intestinal colonization of APEC. Furthermore, the improvements in cecal microbiota and fermentation pattern, along with attenuation of cecal E. coli virulence resulting from XOS supplementation, could also support the maintenance of intestinal health in APEC-challenged broilers. [ABSTRACT FROM AUTHOR]

Simple Summary: There has been an exponential increase in demand for poultry meat and eggs worldwide. Therefore, it is essential to keep coccidiosis under control in broilers to fulfill the increase in demand for protein. The objective of this study was to assess the efficacy of two ionophore coccidiostats against coccidiosis and their impact on broiler gut health and performance. Both the ionophores were effective in treatment against coccidiosis, and out of the two, narasin demonstrated superiority in terms of improved performance parameters compared with salinomycin. This finding is highly important as it significantly focuses on sustainable poultry and, in turn, can help prevent economic losses and maintain broiler health. The objective of this study was primarily to assess the different performance impacts of two ionophore coccidiostats (narasin and salinomycin) used to manage coccidiosis. While both products may be efficacious in controlling disease challenges, previous literature has suggested that some ionophores are less well tolerated by the broiler chickens. In this study, we were particularly interested to know how the use of different coccidiostat programs translates into broiler health and performance, as measured by zootechnical parameters such as the feed conversion ratio, average daily gain, and final body weight. A total of 352 male Ross 308 one-day-old broilers were randomly divided into two treatment groups (T1 and T2). Treatment 1 included a basal diet (BD) + nicarbazin/narasin (Maxiban®, Elanco) at 100 ppm 0–24 days, narasin at 70 ppm 25–42 days, and (2) Treatment 2 included basal diet + nicarbazin/narasin at 100 ppm 0–24 days, salinomycin (Sacox®, Huvepharma) at 70 ppm 25–42 days. Efficacy and performance parameters, slaughter analysis, dry matter (DM) in litter, and intestinal integrity (I2) were measured for the broilers from both treatment groups. The findings demonstrated more favorable results for broilers reared in the group diet fed with narasin (in the finisher phase), including higher daily body weight gain, higher final body weight, lower feed conversion ratio value (improved feed efficiency), and higher European Production Efficiency Factor value, compared with the salinomycin-supplemented group. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to assess the efficiency of including the novel protein ingredient Arthrospira platensis or improved soybean meal in a broiler diet. The first experiment aimed to determine the feeding value of soybean meal produced from varieties of soybeans bred for increased amino acid content (SBAA) and improved oil content (SBO) compared to a conventional soybean variety in an ANOVA design fed to Cobb 500 female broilers for 28–42 d. The SBAA and SBO soybeans contained overall higher amino acid content and lower oligosaccharide content compared to the conventional soybean variety in addition to improved oil quality. The second experiment assessed the novel protein ingredient microalgae, Arthrospira platensis (algae), and was conducted to evaluate algae and corn distillers' grain (DDGS) inclusion on broiler performance for a 28–42 d feeding period in Cobb CF05 male broilers with a 2 × 2 factorial treatment array. Prior to the experimental period, all birds were reared on common feeds. In Experiment 1, birds were fed a diet containing 20% inclusion of an experimental soybean source in the form of full-fat soybean meal. In Experiment 2, the four dietary treatments consisted of diets containing algae at inclusion levels of either 0 or 2% and DDGS at inclusion levels of 0% and 8%. Diets were fed to 288 female broilers (Experiment 1) and 384 male broilers (Experiment 2), placed in eight replicate pens of twelve birds, and live performance was assessed from d 28 to 42. At d 42, six birds from each pen were randomly selected and processed for evaluation of carcass traits and incidence of woody breast. For Experiment 1, all performance data were analyzed using a one-way ANOVA using JMP Pro 16 software with diet as the fixed effect and block as a random effect. Statistical significance was considered at p ≤ 0.05. No significant responses were observed for any recorded measurement for live performance, carcass traits, or woody breast. All data in Experiment 2 were analyzed as a full factorial with a mixed model using JMP software with algae, DDGS, and algae × DDGS as fixed effects and block as a random effect. The F-protected Fisher's LSD test was used to separate means when p ≤ 0.05. No significant responses were observed for the algae, DDGS, and algae × DDGS influences on BWG, FI, and FCR or processing characteristics; the ingredient source did not affect bird performance. Experimental soybean lines developed at the University of Arkansas were able to be incorporated into broiler diets without decreasing performance. Algae has the potential to be a protein-contributing ingredient for broilers. [ABSTRACT FROM AUTHOR]

Phytogenic additives such as tannins are characterized as polyphenolic compounds known for their antimicrobial, anti-inflammatory, antioxidant, and immunostimulatory properties that have been used to enhance the performance, intestinal health, and meat quality of broiler chickens. The objective of this experiment was to evaluate the effects of increasing dietary supplementation of tannins from Acacia mearnsii on the intestinal morphometrics, litter moisture, and growth performance of broiler chickens. A total of 1400 Cobb 500 one-day-old male chicks were randomly distributed into five dietary treatments with eight replicates (35 birds/pen) until 42 days of age. The treatments consisted of Salmonella Heidelberg-challenged groups supplemented with 0, 300, 500, 700, or 900 mg/kg tannin from Acacia mearnsii. A four-phase feeding program was used with pre-starter, starter, grower, and finisher feeds. At 3 days of age, birds were orally gavaged with an S. Heidelberg culture. Feed intake, body weight gain (BWG), and feed conversion ratio (FCR) were evaluated until day 42. The morphometry of duodenum, jejunum, and ileum was measured at 7 and 42 days of age. From 1 to 28, 1 to 35, and 1 to 42 days of age, tannin supplementation for broilers under S. Heidelberg challenge led to quadratic increases (p < 0.05) in BWG, with optimal responses at 265, 412, and 456 mg/kg, respectively. No effects of tannin were observed on FCR in all periods. Villus height was similar in all segments on day 7 (p > 0.05); however, on day 42, tannin supplementation that improved villus height of the ileum was 600 mg/kg (p = 0.0100). In conclusion, tannins from Acacia mearnsii were able to improve body weight gain and intestinal morphometry of broiler chickens under an imposed challenge of S. Heidelberg. [ABSTRACT FROM AUTHOR]

The use of antibiotics in poultry farming has been associated with bacterial resistance in humans, leading to a ban on their inclusion in chicken diets. Therefore, the objective was to evaluate the effects of probiotics and β-mannanase on the growth performance and intestinal health of broiler chickens challenged by Eimeria maxima and Clostridium perfringens. For this, 2100 one-day-old male Ross 308 chicks were used. The treatments were as follows: T1—Negative control (NC) unchallenged birds; T2—Positive control (PC) challenged with E. maxima + C. perfringens; T3—PC + Antibiotic (Enramycin 8%-125 g/ton); T4—PC + β-mannanase (HemicellHT; 300 g/ton); T5—PC + probiotic (ProtexinTM; 150 g/ton); T6—PC + β-mannanase + probiotic. Significant differences (p < 0.05) were observed from 1 to 42 days in the variables body weight, body weight gain and feed intake, and the NC treatment presented higher values compared to the PC and PC + probiotic groups. The villus/crypt ratio in the duodenum increased in the PC + β-man + prob treatment, differing from the NC, PC and PC + probiotic (p < 0.05) treatments. The use of β-mannanase, probiotics or both together is effective to mitigate the effects of production challenges, through the maintenance of the intestine by modulating action on the cecum microbiome and intestinal morphometry. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the apparent metabolizable energy (AME) and nitrogen-corrected AME (AMEn) of defatted black soldier fly larvae meal (BSM), full-fat dry larvae meal (BSL), and larvae fat (LF) for broiler chickens. The BSM, BSL, and LF contained on a g/kg basis, respectively, crude protein, 459, 399, 0; crude fat, 171, 240, 923; dry matter, 963, 940, 997; neutral detergent fiber, 210, 333, 0; acid detergent fibers, 95, 93, 0; and gross energy (MJ/kg), 22.04, 22.78, 38.16. An AME bioassay was performed wherein broilers were fed four experimental diets (a maize–wheat–soy basal diet and three test diets containing 100 g/kg BSM, BSL, or LF, respectively). The AME of BSM, BSL, and LF was calculated based on the differences between the AME values of basal and test diets (substitution method). The AME and AMEn for BSM, BSL, and LF were determined to be 18.20 and 17.40; 17.60 and 16.50; and 36.50 and 35.60 MJ/kg DM, respectively. There were no significant differences (p > 0.05) between nutrient retention coefficients of dry matter, N, and fat. The results showed that the examined products from black soldier fly larvae are a good source of available energy and crude protein (BSL and BSM) and can be incorporated in broiler diets as alternative protein and energy sources. [ABSTRACT FROM AUTHOR]

This research proposes a low-cost system consisting of a hardware setup and a deep learning-based model to estimate broiler chickens' feed intake, utilizing audio signals captured by piezoelectric sensors. The signals were recorded 24/7 for 19 consecutive days. A subset of the raw data was chosen, and events were labeled in two classes, feed-pecking and non-pecking (including singing, anomaly, and silence samples). Next, the labeled data were preprocessed through a noise removal algorithm and a band-pass filter. Then, the spectrogram and the signal envelope were extracted from each signal and fed as inputs to a VGG-16-based convolutional neural network (CNN) with two branches for 1D and 2D feature extraction followed by a binary classification head to classify feed-pecking and non-pecking events. The model achieved 92% accuracy in feed-pecking vs. non-pecking events classification with an f1-score of 91%. Finally, the entire raw dataset was processed utilizing the developed model, and the resulting feed intake estimation was compared with the ground truth data from scale measures. The estimated feed consumption showed an 8 ± 7% mean percent error on daily feed intake estimation with a 71% R2 score and 85% Pearson product moment correlation coefficient (PPMCC) on hourly intake estimation. The results demonstrate that the proposed system estimates broiler feed intake at each feeder and has the potential to be implemented in commercial farms. [ABSTRACT FROM AUTHOR]

Simple Summary: The global supply of the primary component of poultry feed, i.e., soybean meal, has dwindled due to an imbalance between demand and supply. Hence, there is an urgent need for exploring some cost-effective and environmentally friendly alternative protein sources to ensure sustainable poultry production. The outcomes of the present study exhibited that replacing 12% of soybean meal with either Periplaneta americana or Hermetia illucens improves the growth, blood hematology, gut morphometry, and meat quality of broilers. Consequently, these insects can serve as a viable alternative to traditional protein sources in poultry nutrition, offering a promising solution to meet the rising demand for animal protein, while mitigating the environmental impacts associated with conventional feed ingredients. Insects are becoming increasingly popular as a sustainable and nutritious alternative protein source in poultry feeds, due to their high protein content, low environmental impact, and efficient feed conversion rates. Using insect-based feeds can reduce the need for traditional protein sources like soybean meal (SBM), which often contribute to environmental issues such as deforestation and high water consumption. The current experiments were devised to assess the impacts of the partial replacement of SBM with the American cockroach Periplaneta americana and black soldier fly Hermetia illucens on the performances, hematology, gut morphometry, and meat quality of male broilers (Ross 308). A total of 350, 1-day-old chicks weighing 40.05 ± 0.27 g were divided into 7 dietary treatments (5 pens/treatment and 10 birds/pen) at random, i.e., a 4, 8, or 12% SMB replacement with P. americana and H. illucens. Soybean meal was used as a basal diet and taken as a control. The results indicated that broilers fed on 12% P. americana or H. illucens showed significant improvements (p < 0.05) in feed conversion ratio, live weight, and daily weight gain. Hematological traits significantly improved (p < 0.05). A gut histology showed increased villus height, villus width, crypt depth, and villus height/crypt depth ratios, indicating improved nutrient absorption. Broiler meat fed on 12% P. americana meal had significantly higher redness and yellowness (p < 0.05). Substituting soybean meal with up to 12% P. americana or H. illucens meal in poultry feed can enhance the broilers' growth performance, hematology, gut morphometry, and meat quality. Hence, these findings imply that P. americana or H. illucens meal are viable and constructive alternative protein sources in poultry nutrition, offering a sustainable approach to meet the increasing demand for animal protein across the world. [ABSTRACT FROM AUTHOR]

Simple Summary: In a gut metabolomics analysis of growth-promoting probiotics which enhanced broiler growth, we discovered that β-alanine was significantly elevated as a gut metabolite. Furthermore, β-alanine is known to be synthesized into carnosine or have various biological functions in the body on its own. For these reasons, we evaluated the value of β-alanine as a new feed additive for Eimeria-infected broilers through this study, and our results will serve as a good example of utilizing metabolites revealed through metabolomics. (1) Background: In a metabolomics analysis conducted to investigate the mechanisms behind the growth-promoting effects of probiotics in broilers, β-alanine was found to be significantly elevated. This led to the hypothesis that β-alanine could also contribute to growth-promoting effects in infected broilers. (2) Methods: An in vitro culture system was developed to assess β-alanine's impact on proinflammatory cytokine response in chicken macrophage cells, gut integrity in chicken intestinal epithelial cells, and muscle differentiation in quail muscle cells and primary chicken embryonic muscle cells. In vivo animal feeding studies were then conducted to investigate the effects of dietary β-alanine on various disease parameters in Eimeria maxima-infected broiler chickens. (3) Results: In vitro, β-alanine treatment significantly decreased the gene expression of cytokines in chicken macrophage cells and increased occuldin expression in chicken intestinal epithelial cells. Dietary β-alanine increased the body weight of chickens following Eimeria maxima infection in the H-ALA group. Dietary β-alanine also suppressed cytokines and increased JAM-2 and occludin expression in the H-ALA group compared to the infected group without β-alanine supplementation. (4) Conclusions: These results strongly support the positive effects of dietary β-alanine on intestinal immune responses and gut barrier function in broiler chickens infected with Eimeria maxima. [ABSTRACT FROM AUTHOR]

Simple Summary: This research examined how light exposure during incubation affects broiler chickens after hatch. Incubating eggs were exposed to different light durations during incubation (from none to all the time). After hatching, chicks' growth, stress levels, health, and immune response were checked. Results show that light during incubation did not affect most of these measures; however, chicks exposed to 20 h of light had heavier hearts. Overall, light during incubation does not seem to have a big impact on post-hatch performance. This study evaluated the subsequent effect of photoperiods during incubation on post-hatch growth and stress response of commercial broiler chickens. A total of 875 Ross 308 broiler breeder (48 weeks of age) eggs were hatched using different durations (0, 4, 8, 12, 16, 20, and 24 h a day) of dichromatic light [green and red (495 to 750 nm); 2700 K; 250 lux; SUNJIE; China] throughout the whole period of incubation. A total of 50 0-day-old hatched straight run broiler chicks from each photoperiod during incubation were used to evaluate subsequent growth performance (feed intake, body weight, and feed conversion ratio); stress parameters (physical asymmetry, tonic immobility, and vocalization,); welfare traits (feather score and gait score); carcass traits (live weight, dressed weight, carcass yield, liver weight, gizzard weight, heart weight, abdominal fat weight, breast weight, and leg weight); and serum chemistry (globulin, total protein, cholesterol, glucose, and uric acid). There were no influences of photoperiod during incubation on post-hatch growth, stress parameters, welfare, and carcass traits. Heart yield was higher in birds incubated under 20 h light than in those from the 16 h light group. Incubation under different lighting durations also altered blood biochemical profile but did not influence serum globulin and cholesterol levels. It was concluded that under experimental conditions, incubation of broiler eggs under different lighting durations did not impact subsequent post-hatch performance (21–35 d). [ABSTRACT FROM AUTHOR]

Simple Summary: β-hydroxybutyrate (BHB) is generated as one of the ketone bodies in the liver under fasted and hypoglycemic conditions. While BHB is utilized as an alternative energy substrate in extrahepatic tissues/organs, this ketone body has been reported to exert anti-inflammatory effects via modulating inflammatory signaling cascades. Several bacterial pathogens that originated in hygienic litter conditions consecutively threaten chickens. Lipopolysaccharides, a harmful component of Gram-negative bacteria, cause intestinal and systemic inflammation. Therefore, the management of inflammation is a significant concern in poultry production. However, the therapeutic effects of BHB on inflammation have yet to be investigated in chickens. This study demonstrated that BHB administration can alleviate LPS-induced inflammation in broiler chickens, and the effects could be dependent on the gene expression levels of ketolytic enzymes, BHB dehydrogenase-1 and succinyl-CoA:3-ketoacid CoA transferase, in extrahepatic tissues/organs. This study is the first to show the therapeutic effects of BHB on LPS-induced inflammation in chickens, possibly via the involvement of BHB utilization. Background: This study aimed to evaluate the suppressive effects of β-hydroxybutyrate (BHB) administration on lipopolysaccharide (LPS)-induced inflammation in broiler chickens. Methods: Twenty-day-old male broiler chickens were randomly allocated to three groups, each of which was treated with saline (control), intraperitoneal administration of LPS [1.5 mg/kg body weight (BW), Escherichia coli O127:B8], or LPS plus BHB (3 mmol/kg BW). Results: Plasma albumin and total protein concentration were significantly reduced by LPS administration, while BHB co-treatment partially attenuated the effects. The LPS treatment significantly induced plasma aspartate and alanine aminotransferase activities, and interleukin (IL)-6 concentration, with the increases suppressed by BHB co-treatment (p < 0.05). The LPS treatment significantly increased the gene expression levels of IL-1β, IL-6, and IL-18 in the spleen and peripheral blood monocytes (PBMC), while the increases were partially attenuated by BHB in the spleen. Relatively higher levels of BHB dehydrogenase 1 and succinyl-CoA:3-ketoacid CoA transferase were observed in the spleen and skeletal muscle, while these gene levels were lower in PBMC and the liver. Conclusions: The present results suggest that BHB can suppress LPS-induced inflammation, in which ketolytic enzyme expression levels may be involved in broiler chickens. [ABSTRACT FROM AUTHOR]

Heat stress (HS) is a significant concern in broiler chickens, which is vital for global meat supply in the dynamic field of poultry farming. The impact of heat stress on the ileum and its influence on the redox homeostatic genes in chickens remains unclear. We hypothesized that adding zinc to the feed of heat-stressed broilers would improve their resilience to heat stress. However, this study aimed to explore the effects of organic zinc supplementation under HS conditions on broiler chickens' intestinal histology and regulation of HS index genes. In this study, 512 Xueshan chickens were divided into four groups: vehicle, HS, 60 mg/kg zinc, and HS + 60 mg/kg zinc groups. Findings revealed that zinc supply positively increased the VH and VH: CD in the ileum of the broilers compared to the HS group, while CD and VW decreased in Zn and HS+Zn supplemented broilers. Zn administration significantly increased superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and decreased the enzymatic activities of reactive oxygen species (ROS) and malondialdehyde (MDA) compared to the HS group. In addition, Zn administration significantly increased relative ATP, complex I, III, and V enzyme activity compared to the HS group. Furthermore, the expression of acyl-CoA synthetase long-chain family member 4 (ACSL4), lactate transporter 3 (LPCAT3), peroxiredoxin (PRX), and transferrin receptor (TFRC) in the protein levels was extremely downregulated in HS+Zn compared to the HS group. Zn supply significantly decreased the enrichment of RORγ, P300, and SRC1 at target loci of ACSL4, LPCAT3, and PRX compared to the HS group. The occupancies of histone active marks H3K9ac, H3K18ac, H3K27ac, H3K4me1, and H3K18bhb at the locus of ACSL4 and LPCAT3 were significantly decreased in HS+Zn compared to the HS group. Moreover, H3K9la and H3K18la at the locus of ACSL4 and LPCAT3 were significantly decreased in HS+Zn compared to the HS group. This study emphasizes that organic Zn is a potential strategy for modulating the oxidative genes ACSL4, LPCAT3, PRX, and TFRC in the ileum of chickens via nuclear receptor RORγ regulation and histone modifications. [ABSTRACT FROM AUTHOR]

Simple Summary: Research on broiler feeding has increasingly focused on finding effective alternatives to antibiotic growth promoters (AGPs) due to concerns about antibiotic resistance and antibiotic residues in food products. A total EU-wide ban on AGPs was implemented in 2006. However, 70% of antibiotics are still used in animal treatment, contributing to 700,000 deaths worldwide annually due to antibiotic-resistant infections. As a result, researchers have sought natural alternatives, such as probiotics, prebiotics, enzymes, and plant-based preparations like essential oils, which have shown promise in improving broiler production traits and meat quality. The experiment in this study demonstrated that phytogenic supplements improved the European Production Efficiency Factor (EPEF). Additionally, meat from chickens on the phytogenic diet had better water-holding capacity, higher collagen content, and a favorable profile of amines, ketones, and aldehydes, indicating improved quality. These findings suggest that alternatives to AGPs can enhance broiler chicken production and meat physicochemical properties when used in appropriate doses and proportions. The primary objective of this study was to investigate the impact of a phytogenic additive (PA) in broiler chickens' diet on production, physiochemical parameters, and the profile of volatile organic compounds present in broiler chickens' meat. The experiment was conducted in a commercial chicken house, where Ross 308 broiler chickens were divided into two groups, each consisting of 65,000 broilers. One group was fed a diet supplemented with 100 ppm of PA throughout the rearing period. The primary chemical composition of the meat and its physicochemical parameters were determined. A visual assessment of breast muscles for defects and volatile organic compounds were evaluated using an electronic nose system. No statistically significant differences were shown in the production performance of the chickens; while summarizing all production parameters, a higher EPEF index of 31 points in the experimental group was highlighted. Breast muscle quality showed differences in drip loss and WHC (p ≤ 0.01) in favor of the experimental group, and a lower cutting force value (p ≤ 0.05) was found for breast muscles from the experimental group. The group also had a lower proportion of muscles with a white striping defect, and the results of volatile organic compound profiling showed the most aroma units. [ABSTRACT FROM AUTHOR]

Simple Summary: White striping (WS) is a condition frequently observed in poultry farming, which reduces consumer acceptability and causes economic losses for the industry. Although common, the development of WS during the animal's growth remains unclear. Therefore, the objective of this study was to identify genes involved in the occurrence of WS in broiler chickens at 35 days of age and through which processes they act. For this, breast samples were collected from normal and WS-affected chickens, and complete RNA sequencing was performed. Thirty genes showing an altered expression were identified, of which 23 were more expressed and 7 were less expressed in affected chickens compared to normal ones. Fourteen of these genes were related to WS for the first time and are associated with muscle development (CEPBD, DUSP8, METTL21EP, NELL2, UBE3D), lipid metabolism (PDK4, DDIT4, FKBP5, DGAT2, LIPG, TDH, and RGCC), and collagen (COL4A5 and COL4A6). Genes related to muscle, as well as cellular processes, are possibly involved with the initial phase of WS development. Genes linked to lipid metabolism and collagen may be more related to the progression of this condition. White striping (WS) is a myopathy characterized by the appearance of white stripes parallel to the muscle fibers in the breast of broiler chickens, composed of adipose and connective tissues. This condition causes economic losses and, although common, its etiology remains poorly understood. Hence, the objective was to identify genes and biological mechanisms involved in the early stages of WS using a paternal broiler line that grows slightly slower than commercial ones, at 35 days of age, through the RNA sequencing of the pectoralis major muscle. Thirty genes were differentially expressed between normal and WS-affected chickens, with 23 upregulated and 7 downregulated in the affected broilers. Of these, 14 genes are novel candidates for WS and are implicated in biological processes related to muscle development (CEPBD, DUSP8, METTL21EP, NELL2, and UBE3D), lipid metabolism (PDK4, DDIT4, FKBP5, DGAT2, LIPG, TDH, and RGCC), and collagen (COL4A5 and COL4A6). Genes related to changes in muscle fiber type and the processes of apoptosis, autophagy, proliferation, and differentiation are possibly involved with the initial stage of WS development. In contrast, the genes linked to lipid metabolism and collagen may have their expression altered due to the progression of the myopathy. [ABSTRACT FROM AUTHOR]

Accurate and timely molecular diagnosis of respiratory diseases in chickens is essential for implementing effective control measures, preventing the spread of diseases within poultry flocks, minimizing economic loss, and guarding food security. Traditional molecular diagnostic methods like polymerase chain reaction (PCR) require expensive equipment and trained personnel, limiting their use to centralized labs with a significant delay between sample collection and results. Loop-mediated isothermal amplification (LAMP) of nucleic acids offers an attractive alternative for detecting respiratory viruses in broiler chickens with sensitivity comparable to that of PCR. LAMP's main advantages over PCR are its constant incubation temperature (∼65 °C), high amplification efficiency, and contaminant tolerance, which reduce equipment complexity, cost, and power consumption and enable instrument-free tests. This review highlights effective LAMP methods and variants that have been developed for detecting respiratory viruses in chickens at the point of need. [ABSTRACT FROM AUTHOR]

Simple Summary: This study provides a historical perspective of climate change in relation to chickens and a review of genetic advancements related to heat tolerance in chickens. It highlights the origin of the chickens and how the process of domestication and selective breeding has resulted in genetic variations and increased vulnerability to heat stress. This review also discusses the protective genes and molecular mechanisms, such as heat shock proteins, antioxidants, and immunological response that contribute to heat stress tolerance. Likewise, it discusses the use of further genomic techniques such as the genome-wide association study (GWAS) and quantitative trait locus (QTL) analysis in the identification of genetic variables that contribute to the breeding of broiler chickens with enhanced heat tolerance. Similarly, it highlights the need for including local chickens in breeding programs to enhance genetic diversity. This would help them to better withstand heat stress, addressing the challenge of sustainable poultry production in the context of global warming. Climate change poses a significant threat to the poultry industry, especially in hot climates that adversely affect chicken growth, development, and productivity through heat stress. This literature review evaluates the evolutionary background of chickens with the specific genetic characteristics that can help chickens to cope with hot conditions. Both natural selection and human interventions have influenced the genetic characteristics of the breeds used in the current poultry production system. The domestication of chickens from the Red junglefowl (Gallus gallus) has resulted in the development of various breeds with distinct genetic differences. Over the past few years, deliberate breeding for desirable traits (such as meat production and egg quality) in chickens has resulted in the emergence of various economically valuable breeds. However, this selective breeding has also caused a decrease in the genetic diversity of chickens, making them more susceptible to environmental stressors like heat stress. Consequently, the chicken breeds currently in use may possess a limited ability to adapt to challenging conditions, such as extreme heat. This review focuses on evaluating potential genes and pathways responsible for heat tolerance, including heat shock response, antioxidant defense systems, immune function, and cellular homeostasis. This article will also discuss the physiological and behavioral responses of chicken varieties that exhibit genetic resistance to heat, such as the naked neck and dwarf traits in different indigenous chickens. This article intends to review the current genomic findings related to heat tolerance in chickens that used methods such as the genome-wide association study (GWAS) and quantitative trait loci (QTL) mapping, offering valuable insights for the sustainability of poultry in the face of global warming. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: The ban on the use of antibiotics as growth promoters has compelled the exploration of other alternatives. Acidifiers and essential oils are promising alternatives for antibiotics in poultry production, especially acidifiers provided in drinking water as they are more convenient and reduce the potential corrosion of processing equipment and loss during granulation. This study investigated the effect of acidifier and essential oil supplementation in drinking water on growth performance, intestinal digestive capacity, and immune status in broiler chickens. The results showed that a combination of acidifiers (with formic acid and propionic acid as active ingredients) and essential oils (with eucalyptus essential oil, mint essential oil, and cinnamaldehyde as active ingredients) improved the immune function of broilers and reduced the growth of potential pathogenic microorganisms in the waterline and excreta. In order to evaluate the effects of acidifiers and essential oils in drinking water on growth, intestinal digestive capacity, and immune status in broilers, a total of 480, 1-day-old Arbore Acres broilers were randomly assigned to four treatments including normal tap water (Ctr) and tap water supplemented with acidifier I (ACI), acidifier I and essential oils (ACI+EO), and acidifier II (ACII). Both ACI+EO and ACII increased final body weight. The pH value of the crop and gizzards was reduced by ACI+EO, and ACII decreased the pH values of the proventriculus and gizzards (p < 0.05). Compared with control group, ACI, ACI+EO, ACII significantly enhanced lipase activity in jejunum but ACII decreased the level of serum total cholesterol and total triglyceride (p < 0.05). Compared with the control group, ACI+EO and ACII significantly increased the relative weight of the spleen, increased the level of serum IgA and IgM, and decreased E. coli in excreta, while ACII significantly decreased Salmonella in excreta (p <0.05). All treatments significantly increased Lactobacillus in excreta. In conclusion, ACI+EO improved immune status and ACII was effective in reducing Salmonella and promoting Lactobacillus, contributing to intestinal health. [ABSTRACT FROM AUTHOR]

The evolution of the H5 highly pathogenic avian influenza (HPAI) viruses has led to the emergence of distinct groups with genetically similar clusters of hemagglutinin (HA) sequences. In this study, a consensus H5 HA sequence was cloned into the baculovirus expression system. The HA protein was expressed in baculovirus-infected insect cells and utilized as the antigen for the production of an oil emulsion-based H5 avian influenza vaccine (rBacH5Con5Mut). Twenty-one-day-old SPF chickens were immunized with this vaccine and then challenged at 21 days post-vaccination with clade 2.3.2.1, clade 2.3.4.4, and clade 7.2 of H5 HPAI viruses. The sera of vaccinated chickens exhibited high hemagglutination inhibition (HI) titers against the rBacH5 vaccine antigen, while lower HI titers were observed against the different challenge virus H5 hemagglutinins. Furthermore, the rBacH5Con5Mut vaccine provided 100% protection from mortality and clinical signs. Virus isolation results showed that oropharyngeal and cloacal shedding was prevented in 100% of the vaccinated chickens when challenged with clade 2.3.2.1 and clade 2.3.4.4 H5 viruses. When the rBacH5Con5Mut vaccine candidate was administrated at one day of age, 100% protection was demonstrated against the challenge of clade 2.3.4.4 virus at three weeks of age, indicating the potential of this vaccine for hatchery vaccination. Overall, A single immunization of rBacH5Con5Mut vaccine candidate with a consensus HA antigen can protect chickens against different clades of H5 HPAI viruses throughout the rearing period of broiler chickens without a boost, thus fulfilling the criteria for an efficacious broad-spectrum H5 avian influenza vaccine. [ABSTRACT FROM AUTHOR]

This study was undertaken to evaluate and compare the efficacy of different multi-antigen vaccines, including heat-inactivated, whole lysate, and subunit (outer membrane proteins [OMPs]) C. jejuni vaccines along with the immunostimulant CpG ODN in controlling Campylobacter colonization in chickens. In the first trial, 125 μg of C. jejuni OMPs and 50 μg of CpG ODN were administered individually or in combination, either in ovo to chick embryos or subcutaneously (SC) to one-day-old chicks. In the second trial, different concentrations of C. jejuni antigens (heat-killed, whole lysate, and OMPs) were administered SC to one-day-old chicks. The results of the first trial revealed that SC immunization with the combination of CpG ODN and C. jejuni OMPs elevated interferon (IFN)-γ, interleukin (IL)-1β, and IL-13 gene expression in the spleen, significantly increased serum IgM and IgY antibody levels, and reduced cecal C. jejuni counts by approximately 1.2 log10. In contrast, in ovo immunization did not elicit immune responses or confer protection against Campylobacter. The results of the second trial showed that SC immunization with C. jejuni whole lysate or 200 μg OMPs reduced C. jejuni counts by approximately 1.4 and 1.1 log10, respectively. In conclusion, C. jejuni lysate and OMPs are promising vaccine antigens for reducing Campylobacter colonization in chickens. [ABSTRACT FROM AUTHOR]

Simple Summary: Plant-derived compounds, also known as phytogenics, are gaining popularity in the poultry industry as an effective replacement for antibiotic growth promoters, whose wide and irrational use damages the ecosystem and health of animals and humans. Phytogenics are known for improving poultry's health and production performance. These effects are closely related to the cecal microbiota of chickens, which highlights the importance of studying the effects of any feed additive related to gut microbial communities. In this study, we assessed the effects of a phytogenic blend with and without casein in high amounts on cecal microbiota composition and diversity using an artificial gastrointestinal system (CALIMERO-2) that mimics the physiology of a chicken's cecum. The phytogenic blend promoted the abundance of bacteria associated with energy metabolism and production performance in poultry and decreased the presence of opportunistic pathogens. This study showed promising feed additives that can be used as growth promoters for poultry; however, testing in living broiler chickens to prove these data is needed, as artificial GI systems cannot fully reproduce the intestinal physiology of animals. Phytogenic blends (PBs) consist of various bioactive plant-derived compounds that are used as growth promoters for farm animals. Feed additives based on PBs have beneficial effects on farm animals' production performance, health, and overall well-being, as well as positive modulating effects on gut microbiota. In this study, we used a validated in vitro cecal chicken alimentary tract model (CALIMERO-2) to evaluate the effects of a PB (a mix of components found in rosemary, cinnamon, curcuma, oregano oil, and red pepper), alone or in combination with casein (control), on poultry cecal microbiota. Supplementation with the PB significantly increased the abundance of bacteria associated with energy metabolism (Monoglobus) and growth performance in poultry (Lachnospiraceae UCG-010). The PB also decreased the abundance of opportunistic pathogens (Escherichia-Shigella) and, most importantly, did not promote other opportunistic pathogens, which indicates the safety of this blend for poultry. In conclusion, the results of this study show promising perspectives on using PBs as feed additives for poultry, although further in vivo studies need to prove these data. [ABSTRACT FROM AUTHOR]

The composition of the intestinal microbiota can influence the metabolism and overall functioning of avian organisms. Therefore, the objective of this study was to evaluate the effect of three different probiotics and an antibiotic on the microbiomes of 1.400 male Cobb® broiler raised for 42 days. The experiment was conducted with the following treatments: positive control diet (basal diet + antibiotic); negative control diet (basal diet without antibiotic and without probiotic); basal diet + Normal Avian Gut Flora (NAGF); basal diet + multiple colonizing strain probiotics (MCSPs); and basal diet + non-colonizing single strain probiotics (NCSSPs). The antibiotic (enramycin—antibiotic growth promoter) and probiotics were administered orally during all experiment (1 to 42 days), mixed with broiler feed. To determine the composition of the microbiota, five samples of ileal digesta were collected from 42-day-old chickens of each experimental group. The alpha and beta diversity of the ileal microbiota showed differences between the groups. MCSPs presented greater richness and uniformity compared to the positive control, negative control, and NCSSPs treatments, while the negative control exhibited greater homogeneity among samples than NCSSPs. MCSPs also showed a higher abundance of the genus Enterococcus. There were differences between the groups for low-abundance taxa (<0.5%), with NAGF showing higher levels of Delftia, Brevibacterium, and Bulleidia. In contrast, NCSSPs had a higher abundance of Ochrobactrum, Rhodoplanes, and Nitrospira. It was concluded that the treatments analyzed in this study induced modulations in the ileal microbiota of the chickens examined. [ABSTRACT FROM AUTHOR]

Bacterial chondronecrosis with osteomyelitis (BCO) lameness is a major welfare issue for broiler production worldwide affecting approximately 1.5% of broilers over 42 days old. Excessive body weight gain causes mechanical stress on long bones, leading to micro-fractures. This condition induces a bacterial infection of fractures, resulting in bone necrosis and eventual BCO lameness. Increasing gut integrity and supporting Calcium metabolism contribute to the optimal bone structure and subsequently reduce BCO lameness. Probiotics thus provide an excellent strategy for alleviating BCO due to the improvement of intestinal integrity and barrier function. Accordingly, the present study investigated the lameness reduction through the feed supplementation of a selected probiotic. Broiler chickens were assigned to three treatments, including a control litter group (FL), a PoultryStar®Bro probiotic fed group (BRO), and a control wire-flooring group (CW) designed to induce BCO lameness. The probiotic significantly decreased lameness by 46% compared to the control group (p < 0.05). The most predominant bacteria identified from the BCO lesions were Staphylococcus cohnii and Staphylococcus lentus. Moreover, significant increments of tight junction gene expression in jejunum and ileum, plus numerical improvements of body weight gain (BW; +360 g) and feed conversion ratio (FCR; −12 pts) were observed in BRO-supplemented birds. [ABSTRACT FROM AUTHOR]

Simple Summary: Methionine (Met), as the first limiting amino acid in a broiler's diet, plays an important role in protein synthesis, methyl donor, and cell proliferation. Therefore, determining the accurate requirement of Met is of great importance for improving broiler production. However, the optimal L-Met requirement of yellow-feathered broilers remains undetermined at different growth rates. The aim of the trial was to explore the effects of L-Met on growth performance, feather traits, Met-metabolizing enzyme activities, bioavailability, and intestinal morphological characteristics of medium-growing, yellow-feathered broiler chickens compared with DL-Met during the starter phase. Based on the findings, dietary supplementation with L-Met or DL-Met has beneficial effects on the growth performance, feather traits, and intestinal morphology of medium-growing, yellow-feathered broilers aged 1 to 30 d by decreasing the enzyme activities of Met methylation (MAT) and increasing the enzyme activities of the sulfur transfer pathway (CBS), and supplementation with L-Met served a better function compared with DL-Met. The relative efficacy of L-Met to DL-Met was 142.5% for average daily gain (ADG) of yellow-feathered broilers. The appropriate dietary Met levels for medium-growing, yellow-feathered broilers are between 0.36~0.38% (supplementation with DL-Met) or 0.32~0.33% (supplementation with L-Met) when based on ADG and feed-to-gain ratio. This experiment investigated the effects of L-Methionine (L-Met) on growth performance, Met-metabolizing enzyme activity, feather traits, and small intestinal morphological characteristics, and compared these with DL-Methionine (DL-Met) for medium-growing, yellow-feathered broilers during the starter phase. Furthermore, the aim was to provide recommendations for the appropriate dietary Met levels in feed. A total of 1584 1-d broilers were randomly divided into 11 treatment groups with six replicates of 24 birds each: basal diet (CON, Met 0.28%), basal diet + L-Met (0.04%, 0.08%, 0.12%, 0.16%, 0.20%), and basal diet + DL-Met (0.04%, 0.08%, 0.12%, 0.16%, 0.20%). The total trial period was 30 days. Compared with broilers fed the basal diet, those fed 0.04 to 0.20% supplemental Met had higher final body weight (FBW), average daily feed intake (ADFI), average daily gain (ADG), and lower feed-to-gain ratio (F: G) (p < 0.05). Compared with DL-Met groups, the L-Met group had higher FBW and ADG (p < 0.05). The relative bioavailability (RBV) of L-Met in ADG of 1–30 d was 142.5%. Chicks fed diets supplemented with L-Met had longer fourth primary feather lengths compared to birds fed the control and diets supplemented with DL-Met (p < 0.05). Compared to the control, birds supplemented with DL-Met or L-Met had an increased moulting score (p ≤ 0.05). Chicks fed diets supplemented with L-Met had lower activities of methionine adenosyl transferase (MAT) compared to those fed the basal diet or supplemented with DL-Met (p < 0.05). Chicks supplemented with either DL-Met or L-Met had higher activities of cystathionine β-synthase (CBS) than those fed the basal diet (p < 0.05). Compared with the control, chicks fed diets supplemented with either DL-Met or L-Met had an enhanced level of albumin in plasma (p < 0.05). There were no obvious differences in the plasma content of uric acid and total protein among the treatments (p > 0.05). Chicks fed diets supplemented with either DL-Met or L-Met had higher villus height and V/C in the duodenal than chicks fed the basal diet (p < 0.05). The jejunum morphology was not affected by either L-Met or DL-Met supplementation (p > 0.05). Therefore, dietary supplementation with DL-Met or L-Met improved the growth performance, feather traits, and intestinal morphological characteristics of medium-growing, yellow-feathered broiler chickens aged 1 to 30 d by decreasing the enzyme activities of Met methylation (MAT) and increasing the enzyme activities of the sulfur transfer pathway (CBS), and supplementation with L-Met showed a better improvement compared with DL-Met. The relative efficacy of L-Met to DL-Met was 142.5% for ADG of yellow-feathered broilers. The appropriate Met levels for medium-growing, yellow-feathered broilers are between 0.36~0.38% (supplementation with DL-Met) or 0.32~0.33% (supplementation with L-Met) when based on ADG and feed-to-gain ratio. [ABSTRACT FROM AUTHOR]

Simple Summary: Aflatoxin B1 (AFB1) is a potent mycotoxin that can severely harm broiler health and performance, leading to reduced growth rates, compromised liver function, and weakened immune function. The study explored the effectiveness of two dietary supplements, hydrated sodium calcium aluminosilicates (HSCASs), and discarded date pits (DDPs) in reducing the harmful effects of AFB1 on broiler chickens. The research involved feeding 240 chickens with different diets: a control diet, a control diet with AFB1, and an AFB1-contaminated diet with either HSCAS or DDP. The results showed that including HSCAS or DDP in the diet improved the chickens' body weight, feed efficiency, and overall health. These improvements were evident through better liver and kidney function, higher protein and glucose levels in the blood, and enhanced digestive efficiency. Remarkably, DDP supplementation also reduced liver size and improved total antioxidant capacity levels, while HSCAS increased protein digestibility. The study concluded that both HSCAS and DDP are effective in reducing the negative impacts of AFB1 on broiler chickens, suggesting they could be valuable natural feed additives in poultry farming to ensure healthier birds and safer food products for consumers. The research aimed to evaluate how effective hydrated sodium calcium aluminosilicates (HSCASs) and discarded date pits (DDPs) are as dietary adsorbents for aflatoxin B1 (AFB1) in enhancing the performance and health of broiler chickens aged 16 to 30 days. A total of 240 Ross 308 straight-run broilers were randomly allocated into four dietary groups, each with 10 replicates: a control diet, a control diet with 1000 ppb AFB1, an AFB1-contaminated diet with 0.5% HSCAS, and an AFB1-contaminated diet with 4% DDP. Incorporating HSCASs or DDPs into the AFB1-contaminated diet resulted in significant improvements across various parameters, involving increased body weight, improved feed conversion ratio, higher dressing percentage, decreased relative weights of kidney and spleen, elevated serum levels of total protein, globulin, and glucose, reduced serum alanine aminotransferase activity, and heightened hepatic protein concentration and glutathione peroxidase activity, along with diminished hepatic malondialdehyde content and glutamic oxaloacetic transaminase activity. Moreover, both supplements led to increased ileal villus height and surface area, enhanced apparent nitrogen-corrected metabolizable energy digestibility, and decreased AFB1 residues in the liver and kidney. Moreover, the dietary inclusion of DDPs significantly decreased relative liver weight, raised serum albumin concentration, lowered serum alkaline phosphatase activity, enhanced hepatic total antioxidant capacity level, and augmented ileal villus width. Conversely, the dietary addition of HSCASs significantly heightened apparent crude protein digestibility. In conclusion, the inclusion of HSCASs and DDPs in AFB1-contaminated diets can mitigate the toxic effects of AFB1 on broiler chickens, with DDPs exhibiting additional advantages in optimizing liver function and gut morphology. [ABSTRACT FROM AUTHOR]

Simple Summary: Soybean meal is the main constituent of poultry feed, and the global supply of soybeans has decreased because of an imbalance between its demand and supply, primarily caused by the growing world population and reduced cultivation area. Therefore, a cheap and environmentally sustainable alternative protein source is urgently needed to maintain the sustainability of poultry production. In this study, we demonstrated that substituting 12% of soybean meal with either fall armyworm larvae or black soldier fly larvae enhances the growth, blood haematology, gut morphometry, and meat quality of broiler chickens. Consequently, soybean meal can be substituted with protein-rich insects in the poultry feed. The primary challenge facing the global animal industry is the scarcity of protein feed resources. Various insects are gaining prominence as innovative feed sources due to their economic, environmentally friendly, and nutritious attributes. The purpose of the present study was to determine the effects of a partial replacement of soybean meal with fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) and black soldier fly Hermetia illucens (Diptera: Stratiomyidae) on the growth performances, blood parameters, gut histology, and meat quality of broilers. A total of 350 1-day-old (40 ± 0.15 g) male chicks (Ross 308) were randomly assigned to seven experimental meals. Each treatment was repeated five times with 50 birds per dietary treatment. The seven dietary treatments included 4, 8, and 12% replacements of SBM with larvae of S. frugiperda and H. illucens. SBM was the basal diet considered the control. The data showed that broilers fed 12% S. frugiperda or H. illucens exhibited a significantly higher (p < 0.05) live weight, average daily weight gain, and improved the feed conversion ratio. Meals with 12% S. frugiperda or H. illucens significantly enhanced (p < 0.05) haematological and gut histological parameters, including villus height, crypt depth, villus width, and villus height/crypt depth ratios. The meat of broilers fed the 12% S. frugiperda diet showed significantly higher (p < 0.05) lightness and yellowness. Replacing soybean meal up to 12% with either S. frugiperda or H. illucens larvae improves the growth performance, blood haematology, gut morphometry, and meat quality traits of broilers. [ABSTRACT FROM AUTHOR]

Simple Summary: Muscle development plays a pivotal role in the growth process of chickens. Clarifying the mechanisms of muscle development holds significant scientific and economic value. In this study, transcriptome sequencing was conducted on muscle tissues from two broilers with differing growth rates, identifying Insulin–like growth factor 2 mRNA binding protein 1 (IGF2BP1) as a potential participant in chicken muscle development via bioinformatics analysis. The identified genes were further validated using overexpression and knockdown approaches. It was found that IGF2BP1 is highly expressed in chicken muscle tissues, and the experimental results indicated that IGF2BP1 expression promotes the proliferation and differentiation of chicken primary myoblasts (CPMs). These findings offer new insights into the regulation of muscle development. Muscle development is a multifaceted process influenced by numerous genes and regulatory networks. Currently, the regulatory network of chicken muscle development remains incompletely elucidated, and its molecular genetic mechanisms require further investigation. The Longsheng-Feng chicken, one of the elite local breeds in Guangxi, serves as an excellent resource for the selection and breeding of high-quality broiler chickens. In this study, we conducted transcriptome sequencing of the pectoral muscles of Longsheng-Feng chickens and AA broiler chickens with different growth rates. Through comprehensive bioinformatics analysis, we identified differentially expressed genes that affect muscle growth and showed that IGF2BP1 is a key participant in chicken muscle development. Subsequently, we employed QRT-PCR, EdU staining, and flow cytometry to further investigate the role of IGF2BP1 in the proliferation and differentiation of chicken myogenic cells. We identified 1143 differentially expressed genes, among which IGF2BP1 is intimately related to the muscle development process and is highly expressed in muscle tissues. Overexpression of IGF2BP1 significantly promotes the proliferation and differentiation of chicken primary myoblasts, while knockdown of IGF2BP1 significantly inhibits these processes. In summary, these results provide valuable preliminary insights into the regulatory roles of IGF2BP1 in chicken growth and development. [ABSTRACT FROM AUTHOR]

Simple Summary: This experiment investigated how male and female broiler chickens respond to a dietary guanidinoacetic acid (GAA) supplementation concerning their growth, body temperature, blood components, carcass traits, and intestinal structure. The results indicated that male broilers grew faster and consumed feed more than females. When given a higher dose of GAA, all broilers gained weight better and had improved feed efficiency. Further, GAA improved intestinal architecture, especially in male broilers. Interestingly, male birds treated with GAA had higher shank and head temperatures compared to females. Overall, this research suggests that GAA supplementation, especially at a higher dose, can enhance broiler growth and intestinal health, which could be beneficial for broilers. It is well known that female and male broilers showcase variations in their growth performance, influenced by various physiological factors. This experiment aims to explore potential differences between female and male broilers concerning growth performance, body temperature, blood metabolites, carcass traits, and intestinal architecture in response to guanidinoacetic acid (GAA) supplementation. A total of 240 Ross 308 broiler chickens were arranged in a 3 × 2 factorial design and randomly allocated into 48 boxes, each containing 5 birds. The experiment comprised six treatments, with eight replicates per treatment. The main factors investigated were dietary GAA levels (0%, 0.06%, and 0.12%) and sex (male and female). Male broilers demonstrated superior body weight gain (BWG) and feed intake (FI) compared to females (p< 0.05). GAA supplementation at 0.12% concentration notably improved BWG and reduced FI and feed conversion ratio (FCR) across experimental phases (p < 0.05). However, interactions between sex and GAA were minimal except for reduced FI and FCR (p < 0.05) in both sexes during early growth stages. Regardless of GAA treatment, the male birds exhibited more elevated shank and head temperatures than the females. Carcass traits were largely unaffected by GAA supplementation or sex, except for higher heart yield in the males. Serum metabolite levels were not different between treatment groups at 10 and 24 days of age, except for a higher level of serum creatinine at 10 days in the female birds with 0.06% GA supplementation (p < 0.05). Intestinal morphology was significantly affected by GAA and sex, depending on the segment of intestine, in which GAA supplementation significantly increased villus height, crypt depth, villus width, surface area, and goblet cell count, while the males consistently exhibited higher values of these parameters than the females, and differences were observed between intestinal segments, especially in the ileum and duodenum, at different ages. In conclusion, the interactions between GAA and sex had minimal influences on growth performance indices. However, male broilers demonstrated a more pronounced response to GAA concerning ileal architecture. This study highlights the importance of supplementing broiler chicken diets with GAA for optimizing male broiler performance and intestinal function. The inclusion of GAA into broiler diets needs further study to reveal the underlying mechanisms driving these sex-specific responses and assess the long-term impacts of GAA supplementation on broiler health and productivity. [ABSTRACT FROM AUTHOR]

Simple Summary: This review explores how the Chlorella vulgaris microalga affects broiler chickens, specifically their growth performance and blood health markers. Our analysis shows that a cumulative intake of approximately 20 g per bird improved growth and feed efficiency, with benefits peaking at this level before levelling off. This amount also enhanced plasma health markers, suggesting that C. vulgaris can support overall broiler health. However, exceeding 20 g diminished these benefits, emphasising the need to determine the optimal intake levels of C. vulgaris. This systematic review examines the effects of cumulative Chlorella vulgaris intake levels on broiler chickens, focusing on growth performance and systemic health markers. The review establishes a clear relationship between cumulative C. vulgaris intake and significant outcomes in poultry nutrition and health through a detailed analysis of various studies. The correlation analysis revealed that cumulative C. vulgaris intake levels ranging from 0.8 to 718 g/bird influenced growth rates and feed efficiency, following sigmoid models. Specifically, intakes of approximately 20 g/bird maximized final body weight (R2 = 0.616, p < 0.001), cumulative body weight gain (R2 = 0.627, p < 0.001) and daily weight gain (R2 = 0.639, p < 0.001). The feed conversion ratio also improved with increasing C. vulgaris intakes up to this level, although this was non-significant (R2 = 0.289, p = 0.117). In addition, similar cumulative C. vulgaris intake levels impacted plasma health markers in broilers, leading to reductions in triacylglycerols and cholesterol and improvements in immunoglobulin levels. These findings underscore the importance of carefully calibrated C. vulgaris supplementation strategies to optimise poultry growth and health without adverse effects. Future research should focus on refining C. vulgaris dosing guidelines and further exploring its long-term effects and mechanisms of action to enhance poultry health and production sustainability. [ABSTRACT FROM AUTHOR]

Simple Summary: Light is a very important parameter in poultry farming. It can influence production, meat quality and welfare. The increasingly popular energy-efficient light-emitting diode (LED) lighting has replaced other light sources in many farms. We aimed to investigate the effects of incandescent light (IL) and LED lighting on production, meat quality parameters and behavior. In the first five weeks, there was a significant difference in body weights between the groups. The feed conversion ratio was more favorable in all weeks in the LED group. Among the meat quality parameters, only the shear force values differed significantly between the groups. Broilers raised under LED lighting were more active, spent more time socializing and rested less. The results indicated that LED lighting positively impacts animal welfare and production efficiency. Many farms have been replacing traditional lighting sources with light-emitting diode (LED) bulbs because of technological modernization. We aimed to investigate the effects of incandescent lighting (IL) and LED lighting on Cobb 500 broiler chickens for six weeks. Production parameters (body weight, feed consumption, feed conversion ratio), calculated slaughter values (yield%, relative breast%, thigh%) and breast meat quality parameters (pH at 45 min and 24 h postmortem, color, drip loss, kitchen equipment losses, shear force, meat composition) were recorded. Non-stop recordings were used to analyze the behavior of the birds during several periods of rearing. The LED group was significantly better in the body weight parameter between week 1 and 5 and the feed conversion ratio between week 2 and 3. The most significant difference in behavior was observed in the middle of the rearing period. The chickens in the LED group spent more time eating, drinking and interacting, and rested less. There was no difference in the meat quality parameters; only shear force was significantly lower in the LED group (1781.9 g/s vs. 2098.8 g/s). According to our results, LED lighting can bring about positive changes in animal production efficiency, behavior and other important characteristics for meat consumers. [ABSTRACT FROM AUTHOR]

Simple Summary: The implementation of antibiotic-free (ABF) and no-antibiotics-ever (NAE) poultry production has prompted interest in identifying viable options to reduce the need for medically important antibiotics (MIA) in animal feed. The Magni-Phi® Ultra (MPU) nutritional specialty product is mainly composed of natural plant extracts (Quillaja saponaria and Yucca schidigera), which are known for their numerous benefits. By evaluating the effects of feeding MPU on the immune response and intestinal permeability of broilers during coccidia challenge at the peak and recovery phases of infection, this study found that intestinal integrity was enhanced and growth performance and immune response were improved when feeding MPU. This study assessed the impact of Magni-Phi Ultra (MPU) inclusion on intestinal integrity and immunity in broiler chickens challenged with coccidia during peak and recovery phases. A total of 128 male Ross 708 broiler chicks were randomly allotted to one of four treatment groups (four chicks/cage). Treatments included an uninfected control (UUC); a coccidial challenge (CC) infected control (IUC); a CC fed salinomycin at 66 ppm (SAL); and a CC fed Magni-Phi Ultra at 0.11 g/kg of diet (MPU). At 16 days post-hatch, all birds in the CC groups were orally gavaged with a 3× dose of a live coccidia vaccine. At 5 dpi, the birds fed MPU and SAL showed decreased plasma FITC-d, oocyte shedding, and lesion scores and higher BWG compared to the IUC birds (p < 0.05). Jejunum IL-17, IL-10, and IFN-ϒ mRNA expression was higher in the IUC compared to the UUC (p < 0.05) group at 5 dpi. At 12 dpi, the birds fed MPU or SAL had lower plasma FITC-d and jejunum IFN-ϒ and IL-10 mRNA expression compared to the IUC birds (p < 0.05). This study indicates that MPU supports intestinal integrity and mucosal immune responses during the peak and recovery phases of infection, which may lead to improved health and performance. [ABSTRACT FROM AUTHOR]

Light pollution is a potential risk for intestinal health in humans and animals. The gut microbiota is associated with the development of intestinal inflammation induced by extended exposure to light, but the underlying mechanism is not yet clear. The results of this study showed that extended exposure to light (18L:6D) damaged intestinal morphology, downregulated the expression of tight junction proteins, and upregulated the expression of the NLRP3 inflammasome and the concentration of pro-inflammatory cytokines. In addition, extended exposure to light significantly decreased the abundance of Lactobacillus, Butyricicoccus, and Sellimonas and increased the abundance of Bifidobacterium, unclassified Oscillospirales, Family_XIII_UCG-001, norank_f__norank_o__Clostridia_vadinBB60_group, and Defluviitaleaceae_UCG-01. Spearman correlation analysis indicated that gut microbiota dysbiosis positively correlated with the activation of the NLRP3 inflammasome. The above results indicated that extended exposure to light induced intestinal injury by NLRP3 inflammasome activation and gut microbiota dysbiosis. Antibiotic depletion intestinal microbiota treatment and cecal microbiota transplantation (CMT) from the 12L:12D group to 18L:6D group indicated that the gut microbiota alleviated intestinal inflammatory injury induced by extended exposure to light via inhibiting the activation of the NLRP3 inflammasome. In conclusion, our findings indicated that the gut microbiota can alleviate intestinal inflammation induced by extended exposure to light via inhibiting the activation of the NLRP3 inflammasome. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonellosis affects the poultry industry globally and is a major cause of bacterial food poisoning in humans. A Salmonella infection in broiler chickens can result in lower growth rates, decreased feed efficiency and higher mortality rates. The inclusion of probiotics in chicken diets enhances their intestinal microbiota and enhances different patterns of cytokine production in response to Salmonella infection. The increasing demand from consumers for chicken products devoid of antibiotics has increased the need to identify alternatives to antibiotics for the management of Salmonella infection, colonization, and carcass contamination in poultry. Through the process of competitive exclusion, probiotics have been shown to inhibit the colonization of the gut by harmful bacteria such as Salmonella and Clostridium perfringens. Probiotic supplementation also regulates the gut flora to protect the host from infections as well as to create bacteriocins, which directly prevent the growth of pathogens. This study was therefore carried out to ascertain whether the supplementation of Pediococcus pentosaceus GT001 can influence the growth performance, meat quality, intestinal development and cecum microbiota of Salmonella typhimurium-challenged broiler chickens. This study evaluated the effects of Pediococcus pentosaceus GT001 on Salmonella typhimurium (S. typhimurium)-challenged broiler chickens. Two hundred Ross 708 broiler day-old chicks with comparable weight were distributed at random into four treatments with five replicates and ten chicks per replicate. The following were the treatment groups: (B) basal diet (control); (B + S) basal diet and birds were challenged with S. typhimurium at 1.0 × 107 cfu/g; (B + P) basal diet + Pediococcus pentosaceus GT001 at 4.0 × 108 cfu/g; (B + P + S) basal diet + P. pentosaceus GT001 at 4.0 × 108 cfu/g and birds were challenged with S. typhimurium at 1.0 × 107 cfu/g. There was a significant reduction (p < 0.05) in the body weight of the Salmonella-infected birds compared to the other treatment groups. However, the FCRs of the broilers were comparable among the different treatment groups (p > 0.05). The lipid profile and liver function indices measured were significantly enhanced in the P. pentosaceus GT001-supplemented groups (B + P and B + P + S) compared to the group that was Salmonella-challenged (p < 0.05) but were similar to those in the control group. The serum antioxidant activities, such as the T-AOC, SOD, CAT, GHS-Px and MDA, were significantly improved in the P. pentosaceus GT001-supplemented groups (B + P and B + P + S) (p < 0.05). The MDA was similar in the B + P and B + P + S groups, but both were significantly lower than the control and the Salmonella groups. The administration of P. pentosaceus GT001 enhanced the lipase and amylase levels in both the serum and intestine of the broilers (p < 0.05). The immunoglobin (IgA, IgG, IgM) and cytokine (IL-10 and IL-6) levels in the serum were significantly higher in the B, B + P and B + P + S treatment groups (p < 0.05). The immune-related organs (bursa and spleen) were significantly influenced in the birds fed with P. pentosaceus GT001. No significant variation was noted among all the dietary treatments in terms of the measured meat quality indices. The small intestinal digesta content of the Salmonella load was below a detectable range after 14 days of infection (p < 0.05). No significant differences were observed among the different treatment groups in terms of the breast pH, drip loss and meat color (p > 0.05). The inclusion of P. pentosaceus GT001 also modified the community structure in the cecum. This indicates that it has health benefits and could be incorporated in the broiler diet. [ABSTRACT FROM AUTHOR]

Simple Summary: As demands for high-quality protein like chicken meat constantly rise, producers and researchers are actively looking for ways to continuously improve chicken health and performance. The present study examined the effectiveness of a novel mannan-rich yeast carbohydrate product to improve chicken growth performance and immunity. We demonstrated that supplementing mannan-rich yeast carbohydrate improved broiler chicken feed efficiency and antibody immune responses. Our study suggested that the novel mannan-rich yeast carbohydrate product has significant potential for use in poultry production. The current study examined the benefits of a novel mannan-rich yeast carbohydrate product (YM) on broiler chicken growth performance and immune response against sheep red blood cells (SRBCs). A total of 144 newly hatched male Cornish cross broiler chicks were randomly assigned to four treatments with 12 cages per treatment and three birds per cage. The treatments were (1) control, basal diet; (2) YCW, basal diet + 1 g/kg yeast cell wall; (3) YM1, basal diet + 0.5 g/kg of a novel yeast mannan-rich product (YM); and (4) YM2, basal diet + 1 g/kg YM. Growth performance was measured at 14, 28, and 35 days of age (d). At 26 and 27 d, nine birds per treatment were immunized intravenously with SRBCs, and antibody responses against SRBCs were analyzed through a hemagglutination assay 7 days post-inoculation. Supplementing YM tended to improve broiler chicken weight gain from 29 to 35 d (p = 0.053). An improvement in the feed conversion ratio (FCR) was observed in the birds fed YM diets during 29–35 d and over the entire experimental period (0–35 d; p < 0.05). Furthermore, birds fed YM2 diets had more robust antibody responses against SRBCs than the control birds (p = 0.033). In conclusion, dietary supplementation of YM improved broiler chicken growth performance and antibody response against SRBCs. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we compared two different methods of raising broiler chickens: modern colony cages and traditional floor systems. We aimed to understand how each system impacts both the production and wellbeing of the chickens. We discovered that, while colony cages excel in maintaining optimal environmental conditions and promoting rapid growth, they also create challenges, such as leg deformities and difficulty standing. Conversely, traditional floor systems present issues such as heat stress, affecting broiler growth. Our findings emphasize the need to achieve a balance between chicken welfare and production objectives in poultry farming. By recognizing these differences, we can strive to enhance broiler rearing practices, ensuring the birds' wellbeing while still meeting the consumer demand for poultry products. This study compares the effects of modern colony cage systems and traditional floor systems on the production and welfare of broiler chickens. Through two trials spanning 35 days each, we evaluated various physiological parameters, including growth performance, bone health, stress responses, and meat quality. Colony cages demonstrated superior thermal regulation and growth performance compared to traditional floor systems, but also exhibited higher frequencies of leg deformity and reduced standing ability. Conversely, the broilers in traditional floor systems experienced heat stress-related challenges, impacting the meat quality. Our findings underscore the need to balance productivity with animal welfare in broiler farming practices. By understanding the distinct impacts of different housing systems, we can work towards improving broiler rearing methods to ensure optimal welfare and production outcomes. [ABSTRACT FROM AUTHOR]

Simple Summary: The abdominal fat of broiler chickens was used as one of the important parts for color evaluation, which directly affects the market price and demand of broilers. This study aimed to identify the contributors and the regulatory network involved in the formation of yellow and white color in abdominal fat. Four xanthophyll compounds were generally significantly correlated with eight metabolites. The high expression of 3-hydroxyanthranilate 3,4-dioxygenase (HAAO) in the yellow abdominal fat group leads to the degradation of tryptophan and its intermediate 5-hydroxyindole compounds, and subsequently to the formation of the four xanthophyll compounds. This study provides a genetic theoretical basis for improving the external appearance and internal quality of chicken abdominal fat. Abdominal fat, which in the past was often regarded as waste and discarded, has in recent years been used as a fat source to produce meat by-products. Yellow abdominal fat has higher economic value. Therefore, improving the color of abdominal fat plays an important role in improving the appearance of meat products. This study aimed to identify the contributors and the regulatory network involved in the formation of yellow and white color in abdominal fat. We found that four xanthophyll compounds were significantly different in yellow and white abdominal fat chicken, including zeaxanthin, lutein, canthaxanthin, and β-cryptoxanthin. There were 551 different and 8 common metabolites significantly correlated with these 4 xanthophyll compounds. Similarly, a total of 54 common genes were identified in 4 common related pathways (Complement and coagulation cascades, Metabolic pathways, PPAR signaling pathway, Carbon metabolism) of the 8 common metabolites. The high expression of HAAO in the yellow abdominal fat group leads to the degradation of tryptophan and its intermediate 5-hydroxyindole, and subsequently to the formation of the four xanthophyll compounds. This process is also regulated by tyrosine, kynurenine 3-monooxygenase (KMO), homogentisate 1, 2-dioxygenase (HGD), etc. Together, these findings show the effect of tryptophan on abdominal fat color, as well as a negative regulatory effect of HAAO and 5-hydroxyindole on the production of xanthophyll compounds involved in abdominal fat coloration. [ABSTRACT FROM AUTHOR]

Simple Summary: Necrotic enteritis caused by Clostridium perfringens (CP) is an important disease for the poultry industry. It leads to decreased growth and production performance in chickens. Bacillus amyloliquefaciens SC06 (BaSC06) is known to play a role in preventing damage from the bacterial infection. However, whether CP could affect brain function and behavior and whether BaSC06 has a preventive role in infected animals are not yet reported. Thus, the aim of this study was to investigate whether BaSC06 has a preventative effect on broiler chickens infected by CP. Our results showed that CP is associated with a reduction in stress and fear-related behaviors and causes pathological damage to the pia and cortex of the brain, as well as inhibiting the expression of genes related to stress, while the treatment of BaSC06 alleviates these adverse effects. Poultry studies conducted on Clostridium perfringens (CP) mainly focus on the effects of intestinal health and productive performance. Notably, the probiotic Bacillus amyloliquefaciens SC06 (BaSC06) is known to play a role in preventing bacterial infection. However, whether CP could induce the changes in brain function and behaviors and whether BaSC06 could play roles in these parameters is yet to be reported. The aim of this study was to evaluate the effects of BaSC06 on stress-related behaviors and gene expression, as well as the brain morphology and mRNA sequence of the hypothalamus in broiler chickens. A total of 288 one-day-old chicks were randomly divided into four groups: (1) a control group with no treatment administered or infection; (2) birds treated with the BaSC06 group; (3) a CP group; and (4) a BaSC06 plus CP (Ba_CP) group. The results showed that stress and fear-related behaviors were significantly induced by a CP infection and decreased due to the treatment of BaSC06. CP infection caused pathological damage to the pia and cortex of the brain, while BaSC06 showed a protective effect. CP significantly inhibited hypothalamic GABA and promoted HTR1A gene expression, while BaSC06 promoted GABA and decreased HTR1A gene expression. The different genes were nearly found between the comparisons of control vs. Ba group and Ba vs. CP group, while there were a great number of different genes between the comparisons of control vs. Ba_CP as well as CP vs. Ba_CP. Several different gene expression pathways were found that were related to disease, energy metabolism, and nervous system development. Our results will help to promote poultry welfare and health, as well as provide insights into probiotics to replace antibiotics and reduce resistance in the chicken industry. [ABSTRACT FROM AUTHOR]

Simple Summary: Lameness induced by bacterial chondronecrosis with osteomyelitis poses a significant challenge in the poultry industry globally. It is caused by pathogenic bacteria entering the bird's bloodstream via the skin, respiratory tract, or digestive system. These bacteria are then disseminated hematogenously and infest the osteochondrotic crypts from chronic fractures resulting from mechanical stress caused by fast growth rate and heavy body weight, leading to lameness. The objective of this research is to identify the ideal timing for Availa® ZMC supplementation in broiler lameness reduction using an aerosol transmission challenge model, with a hypothesis that providing Availa® ZMC through the initial four weeks of the production cycle will optimally strengthen skeletal bones, improve intestinal integrity, and enhance immune responses. The results show that including 0.15% Availa® ZMC in the broiler diet during the first 28 days is the optimal timing. This approach provides a level of protection against BCO lameness nearly equivalent to that of birds fed with the same inclusion level throughout the entire production cycle. Our prior research demonstrated a 20% to 25% reduction in bacterial chondronecrosis with osteomyelitis (BCO) lameness in broilers with organic Zn, Mn, and Cu (Availa® ZMC) supplementation. Expanding on this, we investigated the optimal timing for Availa® ZMC feeding to mitigate BCO lameness and reduce feed additive costs in the poultry industry. In this study, we compared the application of 0.15% Availa® ZMC for 56 days, the first 28 days, and the last 28 days. The experimental design was a randomized block design involving 1560 one-day-old chicks distributed across two wire-floor pens as BCO source infection and four treatment groups with six replicates. The source of BCO infection exhibited a cumulative lameness incidence of 83%, whereas the negative control group showed a 77% cumulative incidence of lameness (p = 0.125). Administering 0.15% of Availa® ZMC during the initial 28 d resulted in a 41.3% reduction in BCO incidence, significantly different from the supplementation during the last 28 d (p < 0.05). However, this reduction did not differ substantially (p > 0.05) from the 56d application period. Hence, administering 0.15% Availa® ZMC during the first four weeks emerges as the optimal timing protocol, providing a defense against lameness comparable to the continuous supplementation throughout the complete production duration. Implementing this feeding approach reduces the cost of feed additive, promotes the health of skeletal bones, and effectively protects against BCO lameness in broilers, offering a valuable consideration for producers seeking optimal outcomes in the poultry industry. [ABSTRACT FROM AUTHOR]

As societal progress elevates living standards, the focus on meat consumption has shifted from quantity to quality. In broiler production, optimizing meat quality has become paramount, prompting efforts to refine various meat attributes. Recent advancements in sequencing technologies have revealed the genome's complexity, surpassing previous conceptions. Through experimentation, numerous genetic elements have been linked to crucial meat quality traits in broiler chickens. This review synthesizes the current understanding of genetic determinants associated with meat quality attributes in broilers. Researchers have unveiled the pivotal insights detailed herein by employing diverse genomic methodologies such as QTL-based investigations, candidate gene studies, single-nucleotide polymorphism screening, genome-wide association studies, and RNA sequencing. These studies have identified numerous genes involved in broiler meat quality traits, including meat lightness (COL1A2 and ACAA2), meat yellowness (BCMO1 and GDPD5), fiber diameter (myostatin and LncIRS1), meat pH (PRDX4), tenderness (CAPN1), and intramuscular fat content (miR-24-3p and ANXA6). Consequently, a comprehensive exploration of these genetic elements is imperative to devise novel molecular markers and potential targets, promising to revolutionize strategies for enhancing broiler meat quality. [ABSTRACT FROM AUTHOR]

Further reductions of crude protein in broiler diets may cause essential amino acids traditionally considered to be supplied at adequate levels to become limiting. Requirement data for histidine are currently scarce and this amino acid is uniquely able to be stored within the body. Thus, the objectives of this study were to evaluate female Cobb 500 broiler growth performance and carcass characteristic responsiveness to increasing digestible histidine to digestible lysine ratios (dHis:dLys) during a 22- to 42-day feeding period and determine if dHis:dLys in preceding feeds influence the former responses. Starter diets were formulated to contain dHis:dLys of 33% or 38% and grower diets were formulated to contain dHis:dLys of 28%, 33%, 38%, or 43%, which gave rise to a 2 × 4 factorial arrangement of treatments. No interactions (p > 0.05) between the starter or grower diet dHis:dLys occurred. Increasing the dHis:dLys from 22 to 42 days resulted in body weight gain, feed conversion ratio, and total breast meat yield quadratic responses (p ≤ 0.05). Additionally, it appears that dHis:dLys between 33% and 38% fed during the starter phase does not influence broiler responsiveness to different dHis:dLys during the grower phase. [ABSTRACT FROM AUTHOR]

The study aimed to quantify carcass fat and protein retention, and the efficiency of carcass energy utilization (Kre) resulting from feeding broiler chickens diets containing wheat, maize or mixtures of both as the major cereal ingredient. The apparent metabolizable energy (AME) of the four cereal samples was determined in adult cockerels. There was a linear (p < 0.001) increase in AME with increasing amounts of maize within the four cereal mixtures, with analyses indicating that the AME of maize was 1.4 MJ/kg greater than that of wheat. A second bioassay with growing chickens was used to determine Kre in each cereal, measured as carcass fat and protein from 7 to 21d age. Increasing proportions of maize resulted in linear increases in carcass fat and energy retained from fat (p < 0.001). However, the carcass protein and energy retained from protein did not follow the same pattern as fat (p = 0.121), but rather decreased numerically (L = 0.032). The Kre tended (p = 0.060) to increase with greater proportion of maize in a linear fashion (L = 0.009). Although AME values of cereals were confirmed to be additive, this could not be confirmed for Kre. This data can be used for optimizing energy utilization models for growing broilers. [ABSTRACT FROM AUTHOR]