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Introduction: Clinical metritis (CM) has significant costs to dairy producers. Current treatment strategy involves systemic antibiotics; however, there is increasing concern about judicious antibiotic use. The study objective was to evaluate the effects of a non-antibiotic treatment vs. systemic antibiotic therapy on the vaginal discharge microbiome of dairy cows diagnosed with CM at 7 ± 3 DIM (days in milk). We hypothesize that both treatment methods will have a similar impact on the reproductive microbiome due to broad-spectrum bactericidal activity; therefore, there will not be significant differences amongst the microbiota after the completion of therapy. Methods: Cows from a central Pennsylvania dairy were screened for CM at 7 ± 3 days DIM using a Metricheck™ device (n = 351). Cows with red-brown watery discharge were diagnosed with CM and eligible for enrollment. Eligible cows (n = 77) were blocked by parity and randomly allocated to one of two treatments starting on the day of diagnosis: (1) Intrauterine dextrose (DEX, n = 38): 1 l of an intrauterine 50% dextrose solution for 3 days, and (2) Systemic ceftiofur (CONV, n = 39): two injections of ceftiofur (6.6 mg/Kg of BW; Excede, Zoetis Inc.) 72 h apart. Cows were evaluated for clinical cure rate at 7 ± 3 and 14 ± 3 days post-diagnosis. Vaginal discharge samples were collected using the Metricheck™ at enrollment day [study day (sd) 0, pre-treatment], sd 7, and sd 14 for a subset of enrolled cows (DEX = 13, CONV = 14). Vaginal discharge samples were analyzed with 16S rRNA sequencing to evaluate changes in the microbiome between treatments. Results: After treatment, there were only minor differences within the microbiome between the two treatments indicating the potential suitability of dextrose as an antibiotic-alternative treatment. Alpha diversity did not differ (Welch's t -test) between the treatments at any of the time points. Beta diversity based on PERMANOVA analysis did differ between treatments at sd 0 (P = 0.014) and again at sd 14 (P = 0.028), but not at sd 7 (P = 0.261). Discussion: While 16S rRNA analysis does not provide information on bacterial viability, the relative similarity of the microbiome between the two groups immediately following treatment might suggest that intrauterine dextrose could be utilized as an alternative treatment for CM. [ABSTRACT FROM AUTHOR]

Introduction: Platelet lysate (PL) demonstrates antimicrobial and anti-inflammatory properties offering potential for treatment of bacterial pneumonia in horses. It remains unknown whether nebulization is suitable for PL administration in horses. This pilot study characterized particle size and flow rate of pooled equine PL (single preparation) nebulized using an equine-specific nebulizer (Flexivent®). Methods: Protein composition and antimicrobial activity were compared before and after nebulization. Protein composition was evaluated according to growth factor, antimicrobial peptide and cytokine concentrations and proteomic analysis. To evaluate antimicrobial activity, bacterial growth inhibition [maximum growth (μmax); carrying capacity (K)] were determined for E. coli, Streptococcus equi subsp zooepidemicus and Rhodococcus equi (WT and MDR) using pre- and post-nebulized PL concentrations of 50%. Results: Flow rate and median particle size were 0.8 ml/min and 4.991 μm with 52% of particles ≤ 5 μm. Differences in PL protein composition were detected with nebulization. For E. coli and S. zooepidemicus , nebulization did not alter effect of PL on growth parameters. PL treatments decreased K for S. zooepidemicus (p = 0.009) compared to BHI. For R. equi K was increased post- vs. pre-nebulization (WT and MDR) and μmax increased pre- vs, post-nebulization (MDR). PL treatments increased K and μmax for MDR R. equi and μmax for WT R. equi compared to BHI (p ≤ 0.05). Conclusion: Nebulization of PL in vitro is technically feasible. The results of this study support further investigation to better characterize the effect of nebulization on PL and its suitability for nebulization in horses. [ABSTRACT FROM AUTHOR]

Intensive poultry rearing needs preventive strategies against diseases, several of which are little or not containable by vaccinations. Short- and medium-chain fatty acids (SMCFAs) and chestnut tannin (CHT), both by-products of two different industrial production chains, are very effective antimicrobials. The inclusion level of these additives in the diet is fundamental because a detrimental effect on the gut microbiome can occur if the dose is too high, compromising the animal welfare and performance. Hence, the aim of this trial was to test the effect of a blend (BL; 1:1, w/w) of SMCFAs (fatty acids from C4:0 to C9:0) and CHT extract (CTE) as feed additive in broiler feeding. One hundred one-day-old Ross 308 male chicks were randomly assigned to 5 dietary treatments (4 replicates; 20 pens; 5 animals per pen): control diet (CON), FAS diet (with 1.5 g/100g on dry matter (DM) of SMCFAs), CTE diet (with 1.5 g/100g on DM of CHT extract), BL1 diet (with 1.5 g/100g on DM of BL), and BL2 diet (with 3.0 g/100g on DM of BL). Among the parameters evaluated (weight gain; feed intake; feed efficiency; dressing out), the only differences were observed for the feed intake. In particular, the feed intake of CON (2.876 kg), FAS (2.773 kg), CTE (2.882 kg), and BL1 (2.858 kg) were comparable while the feed intake of BL2 (2.717 kg) was lower than the other diets except for FAS which was similar (p = 0.0010). The microbial community in the caecum was described by high-throughput sequencing of 16S rRNA gene amplicons and was similar between the treatments both in terms of alpha-diversity and beta-diversity. The results of this trial evidenced that no detrimental effect on growth performances or on gut microbiome occurred when birds were fed the blend of SMCFAs and CHT extracts at the inclusion levels tested in this study. HIGHLIGHTS: Short- and medium-chain fatty acids and chestnut tannins are alternatives to conventional antimicrobials Natural antimicrobials improve the sustainability of poultry production Short- and medium-chain fatty acids and chestnut tannins did not alter the gut microbiota of broiler [ABSTRACT FROM AUTHOR]

Simple Summary: Phage therapy offers a targeted approach to combat antibiotic-resistant infections. In this study, we isolated a phage named vB_PmuM_CFP3 (CFP3) from a chicken farm to specifically target Pasteurella multocida, the bacterium responsible for avian cholera. Our research showed that CFP3 effectively attacks the bacteria while being stable under conditions suitable for poultry treatment. Safety checks revealed that CFP3 lacks genes related to antibiotic resistance, making it a safer option. Our findings suggest that CFP3 could be a viable alternative treatment for birds without harming other beneficial bacteria. While the initial findings are promising, further studies are needed to confirm these results in living animals. Our work provides an important step towards using phage therapy for safer, sustainable management of avian cholera. The rise of antibiotic-resistant bacterial infections necessitates alternative therapeutic strategies, such as phage therapy. This study investigates the potential of phage vB_PmuM_CFP3 (CFP3) as a therapeutic agent against avian cholera caused by Pasteurella multocida (P. multocida). Phage CFP3 was isolated from the feces and wastewater of a laying hen farm and underwent comprehensive biological characterization, including host range, lytic activity, and environmental stability. Transmission electron microscopy revealed CFP3′s typical myovirus morphology, with a head diameter of approximately 60 nm and a tail length of about 120 nm. CFP3 demonstrated high stability across a pH range of 4–10 and temperatures of 30–40 °C, making it suitable for oral administration in poultry. The phage exhibited a latent period of about 90 min and an optimal multiplicity of infection (MOI) of 1. Despite its narrow host range, with a lysis rate of 28.2% against avian-derived type A P. multocida, CFP3′s specificity minimizes impact on non-target bacteria. Whole-genome sequencing revealed a 32,696 bp linear double-stranded DNA genome with 46 predicted open reading frames (ORFs) and no tRNA or antibiotic resistance genes, enhancing its safety profile. Phylogenetic analysis indicated a close evolutionary relationship with Haemophilus phages HP1, HP2, and Pasteurella phage F108. While CFP3 shows promise as a precision therapeutic tool, further in vivo studies are required to evaluate its efficacy and safety. Future research should focus on expanding the phage library, optimizing phage mixtures, and exploring synergistic effects with other antimicrobial strategies. This study provides foundational data supporting the development of CFP3 as a viable alternative to antibiotics for controlling avian cholera. [ABSTRACT FROM AUTHOR]

Intensive poultry rearing needs preventive strategies against diseases, several of which are little or not containable by vaccinations. Short- and medium-chain fatty acids (SMCFAs) and chestnut tannin (CHT), both by-products of two different industrial production chains, are very effective antimicrobials. The inclusion level of these additives in the diet is fundamental because a detrimental effect on the gut microbiome can occur if the dose is too high, compromising the animal welfare and performance. Hence, the aim of this trial was to test the effect of a blend (BL; 1:1, w/w) of SMCFAs (fatty acids from C4:0 to C9:0) and CHT extract (CTE) as feed additive in broiler feeding. One hundred one-day-old Ross 308 male chicks were randomly assigned to 5 dietary treatments (4 replicates; 20 pens; 5 animals per pen): control diet (CON), FAS diet (with 1.5 g/100g on dry matter (DM) of SMCFAs), CTE diet (with 1.5 g/100g on DM of CHT extract), BL1 diet (with 1.5 g/100g on DM of BL), and BL2 diet (with 3.0 g/100g on DM of BL). Among the parameters evaluated (weight gain; feed intake; feed efficiency; dressing out), the only differences were observed for the feed intake. In particular, the feed intake of CON (2.876 kg), FAS (2.773 kg), CTE (2.882 kg), and BL1 (2.858 kg) were comparable while the feed intake of BL2 (2.717 kg) was lower than the other diets except for FAS which was similar (p = 0.0010). The microbial community in the caecum was described by high-throughput sequencing of 16S rRNA gene amplicons and was similar between the treatments both in terms of alpha-diversity and beta-diversity. The results of this trial evidenced that no detrimental effect on growth performances or on gut microbiome occurred when birds were fed the blend of SMCFAs and CHT extracts at the inclusion levels tested in this study.HIGHLIGHTS Short- and medium-chain fatty acids and chestnut tannins are alternatives to conventional antimicrobials Natural antimicrobials improve the sustainability of poultry production Short- and medium-chain fatty acids and chestnut tannins did not alter the gut microbiota of broiler

Simple Summary: Plant extracts contain a series of bio-active ingredients. Particularly, flavonoids exert efficient bio-activity and excellent microbial modulatory capacities, which are considered to be appropriate feed additives in husbandry production. In this study, flavonoids extracted from kudzu leaf (KL) was chosen to investigate their promotive effects on the productive performance and egg quality of layer hens. The results indicate that the kudzu leaf flavonoid (KLF) supplement significantly proliferated probiotics, such as Bifidobacterium sp. and Lactobacillus sp., which may have further interacted with hypothalamus genes, thus decreasing the deformity rate while increasing eggshell strength in the finishing phase. The findings indicate that KLF could be used as an effective feed additive for prolonging laying rates during the late-laying stage and may further improve feed efficiency, thus lowering costs. (1) Background: Improving feed efficiency and the vitality of the reproductive system in the late stage of the egg-laying period is of great significance for prolonging the egg-laying cycle and improving egg quality. In the present study, a new flavonoid, which was extracted from kudzu leaf, was chosen to investigate its effects on the productive performance and egg quality of late-laying hens. (2) Methods: A total of 360 500-day-old Hy-Line Brown layer hens were randomly divided into a control treatment group (no KLF supplementation), and groups that received 0.2%, 0.4%, 0.6%, 0.8%, and 1.0% KLF supplement treatments. Each treatment contained 6 replicates, with 10 hens in each replicate. Productive performance metrics, including the daily egg production, egg weight, the number of deformed eggs, egg quality, egg density, egg shape index, eggshell strength, yolk color, and the Haugh unit, were meticulously recorded for each replicate. Furthermore, microbial communities and hypothalamus gene expressions were investigated based on the results of the productive performance and egg quality. (3) Results: KLF supplementation significantly decreased the deformity rate while significantly increasing the eggshell strength in the finishing phase afterward (p < 0.05). Specifically, hens supplemented with 0.6% KLF possessed the lowest deformed egg rate. KLF supplementation significantly increased the relative abundances of Bifidobacterium sp., Blautia sp., Lactococcus sp., and Lactobacillus sp., while significantly decreasing Parasutterella sp. and Escherichia-Shigella sp. (p < 0.05). Furthermore, the interactive analysis showed the hypothalamus gene expression mainly interacted with probiotics, such as Bifidobacterium sp. and Lactobacillus sp., through ribosome biogenesis, nucleocytoplasmic transport, and cAMP signaling pathways. (4) Conclusions: The findings of the present study indicate that KLF supplementation significantly proliferated probiotics, such as Bifidobacterium and Lactobacillus, which may have further interacted with hypothalamus genes, thus decreasing the deformity rate while increasing eggshell strength in the finishing phase. [ABSTRACT FROM AUTHOR]

IntroductionClinical metritis (CM) has significant costs to dairy producers. Current treatment strategy involves systemic antibiotics; however, there is increasing concern about judicious antibiotic use. The study objective was to evaluate the effects of a non-antibiotic treatment vs. systemic antibiotic therapy on the vaginal discharge microbiome of dairy cows diagnosed with CM at 7 ± 3 DIM (days in milk). We hypothesize that both treatment methods will have a similar impact on the reproductive microbiome due to broad-spectrum bactericidal activity; therefore, there will not be significant differences amongst the microbiota after the completion of therapy.MethodsCows from a central Pennsylvania dairy were screened for CM at 7 ± 3 days DIM using a Metricheck™ device (n = 351). Cows with red-brown watery discharge were diagnosed with CM and eligible for enrollment. Eligible cows (n = 77) were blocked by parity and randomly allocated to one of two treatments starting on the day of diagnosis: (1) Intrauterine dextrose (DEX, n = 38): 1 l of an intrauterine 50% dextrose solution for 3 days, and (2) Systemic ceftiofur (CONV, n = 39): two injections of ceftiofur (6.6 mg/Kg of BW; Excede, Zoetis Inc.) 72 h apart. Cows were evaluated for clinical cure rate at 7 ± 3 and 14 ± 3 days post-diagnosis. Vaginal discharge samples were collected using the Metricheck™ at enrollment day [study day (sd) 0, pre-treatment], sd 7, and sd 14 for a subset of enrolled cows (DEX = 13, CONV = 14). Vaginal discharge samples were analyzed with 16S rRNA sequencing to evaluate changes in the microbiome between treatments.ResultsAfter treatment, there were only minor differences within the microbiome between the two treatments indicating the potential suitability of dextrose as an antibiotic-alternative treatment. Alpha diversity did not differ (Welch's t-test) between the treatments at any of the time points. Beta diversity based on PERMANOVA analysis did differ between treatments at sd 0 (P = 0.014) and again at sd 14 (P = 0.028), but not at sd 7 (P = 0.261).DiscussionWhile 16S rRNA analysis does not provide information on bacterial viability, the relative similarity of the microbiome between the two groups immediately following treatment might suggest that intrauterine dextrose could be utilized as an alternative treatment for CM.

IntroductionPlatelet lysate (PL) demonstrates antimicrobial and anti-inflammatory properties offering potential for treatment of bacterial pneumonia in horses. It remains unknown whether nebulization is suitable for PL administration in horses. This pilot study characterized particle size and flow rate of pooled equine PL (single preparation) nebulized using an equine-specific nebulizer (Flexivent®).MethodsProtein composition and antimicrobial activity were compared before and after nebulization. Protein composition was evaluated according to growth factor, antimicrobial peptide and cytokine concentrations and proteomic analysis. To evaluate antimicrobial activity, bacterial growth inhibition [maximum growth (μmax); carrying capacity (K)] were determined for E. coli, Streptococcus equi subsp zooepidemicus and Rhodococcus equi (WT and MDR) using pre- and post-nebulized PL concentrations of 50%.ResultsFlow rate and median particle size were 0.8 ml/min and 4.991 μm with 52% of particles ≤ 5 μm. Differences in PL protein composition were detected with nebulization. For E. coli and S. zooepidemicus, nebulization did not alter effect of PL on growth parameters. PL treatments decreased K for S. zooepidemicus (p = 0.009) compared to BHI. For R. equi K was increased post- vs. pre-nebulization (WT and MDR) and μmax increased pre- vs, post-nebulization (MDR). PL treatments increased K and μmax for MDR R. equi and μmax for WT R. equi compared to BHI (p ≤ 0.05).ConclusionNebulization of PL in vitro is technically feasible. The results of this study support further investigation to better characterize the effect of nebulization on PL and its suitability for nebulization in horses.

ABSTRACT: The widespread use of antibiotics causes the development of antibiotic-resistant bacterial strains, which have a severe impact on poultry productivity and human health. As a result, research is continuing to develop safe natural antibiotic alternatives. In the current study, Bacillus pumilus SA388 was isolated from the chicken feces and confirmed to be a probiotic. The selected strain was tested for its antimutagenic and antioxidant capabilities before being employed as a probiotic food supplement and antibiotic alternative. The effect of B. pumilus SA388 impact on broiler chickens' growth performance, gut microbiome, blood biochemical markers, immunological response, and meat quality was also studied. B. pumilus SA388 showed significant bactericidal activity against Streptococcus pyogenes, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella typhi, and Klebsiella pneumonia. A total of 200 chickens were used in the present study, divided equally among four experimental groups (ten birds per group with 5 replicates): group 1 (control, G1) received a basal diet without B. pumilus SA388, group 2 (G2) received a basal diet supplemented with 0.4 mg/kg of B. pumilus SA388, group 3 (G3) received a basal diet supplemented with 0.8 mg/kg of B. pumilus SA388, and group 4 (G4) received a basal diet supplemented with 1.6 mg/kg of B. pumilus SA388. Over 35 d, the B. pumilus SA388-supplemented groups outperformed the G1 in terms of body weight gain, performance index, and feed conversion ratio, with a preference for the G4 treatment. The levels of alanine aminotransferase (ALT), aspartate transaminase (AST), low-density lipoprotein (LDL), and total cholesterol decreased significantly (P < 0.05) with increasing B. pumilus SA388 dosages compared to the control G1 group. Dietary supplementation of B. pumilus SA388 at 1.6 mg/kg (G4) significantly (P < 0.05) resulted in improved lipid profile, immunological response, thyroid function, and gut microbiota compared to the control group (G1). Compared to the broilers in the control treatment (G1), the addition of B. pumilus SA388 to broilers in G4 significantly (P < 0.05) enhanced juiciness, tenderness, aroma, and taste. Adding B. pumilus SA388 to chicken feed at different doses significantly (P < 0.05) decreased average feed intake while increasing economic and relative efficiency measures. In conclusion, B. pumilus SA388 has been proven to be an effective antibiotic and nutritional supplement.

Abstract The targeted depletion of potential gut pathogens is often challenging because of their intrinsic ability to thrive in harsh gut environments. Earlier, we showed that Campylobacter jejuni (C. jejuni) exclusively uses the Type-VI Secretion System (T6SS) to target its prey such as Escherichia coli (E. coli), and phenotypic differences between T6SS-negative and T6SS-positive C. jejuni isolates toward bile salt sensitivity. However, it remains unclear how the target-driven T6SS functionality prevails in a polymicrobial gut environment. Here, we investigated the fate of microbial competition in an altered gut environment via bacterial T6SS using a T6SS-negative and -positive C. jejuni or its isogenic mutant of the hemolysin-coregulated protein (hcp). We showed that in the presence of bile salt and prey bacteria (E. coli), T6SS-positive C. jejuni experiences enhanced intracellular stress leading to cell death. Intracellular tracking of fluorophore-conjugated bile salts confirmed that T6SS-mediated bile salt influx into C. jejuni can enhance intracellular oxidative stress, affecting C. jejuni viability. We further investigated whether the T6SS activity in the presence of prey (E. coli) perturbs the in vivo colonization of C. jejuni. Using chickens as primary hosts of C. jejuni and non-pathogenic E. coli as prey, we showed a marked reduction of C. jejuni load in chickens cecum when bile salt solution was administered orally. Analysis of local antibody responses and pro-inflammatory gene expression showed a reduced risk of tissue damage, indicating that T6SS activity in the complex gut environment can be exploited as a possible measure to clear the persistent colonization of C. jejuni in chickens.

The targeted depletion of potential gut pathogens is often challenging because of their intrinsic ability to thrive in harsh gut environments. Earlier, we showed that Campylobacter jejuni (C. jejuni) exclusively uses the Type-VI Secretion System (T6SS) to target its prey such as Escherichia coli (E. coli), and phenotypic differences between T6SS-negative and T6SS-positive C. jejuni isolates toward bile salt sensitivity. However, it remains unclear how the target-driven T6SS functionality prevails in a polymicrobial gut environment. Here, we investigated the fate of microbial competition in an altered gut environment via bacterial T6SS using a T6SS-negative and -positive C. jejuni or its isogenic mutant of the hemolysin-coregulated protein (hcp). We showed that in the presence of bile salt and prey bacteria (E. coli), T6SS-positive C. jejuni experiences enhanced intracellular stress leading to cell death. Intracellular tracking of fluorophore-conjugated bile salts confirmed that T6SS-mediated bile salt influx into C. jejuni can enhance intracellular oxidative stress, affecting C. jejuni viability. We further investigated whether the T6SS activity in the presence of prey (E. coli) perturbs the in vivo colonization of C. jejuni. Using chickens as primary hosts of C. jejuni and non-pathogenic E. coli as prey, we showed a marked reduction of C. jejuni load in chickens cecum when bile salt solution was administered orally. Analysis of local antibody responses and pro-inflammatory gene expression showed a reduced risk of tissue damage, indicating that T6SS activity in the complex gut environment can be exploited as a possible measure to clear the persistent colonization of C. jejuni in chickens. Highlights: 1. Differential response of C. jejuniT6SS under bile salt stress. 2. T6SS function was probed by deleting its essential functional subunit, Hcp. 3. The presence of prey bacteria facilitates enhanced bile salt influx and oxidative stress in T6SS-positive C. jejuni. 4. Decreased colonization of C. jejuniin chickens by tuning T6SS activity. [ABSTRACT FROM AUTHOR]

Antibiotic-resistant microorganisms may lead to treatment failure and economic losses in the poultry industry and threaten public health. One of the main factors involved in the increasing emergence of antimicrobial resistance is the non-judicious use of antimicrobial agents as growth promoters in poultry and animal production. The search for natural alternatives to growth promoters to antimicrobial agents is continuous and crucial. This investigation focused on the probiotic strains extracted from the gastrointestinal tracts of poultry reared in various habitation types. The selected strain with antioxidant properties was Bacillus toyonensis (BT) M44, used as a probiotic dietary supplement and antibiotic alternative, then investigated its effects on growth performance, blood biochemical parameters, immune response, gut microbiota, and meat quality of IR broilers. Bacillus toyonensis M44 exhibited potent antibacterial activity against MDR microorganisms, as evidenced by MICs ranging from 5% to 10%. A total of 160 IR chicks were allocated into four groups randomly, each consisting of (10 x 4) chicks. The control group was administered a basal diet; the remaining three groups were provided the control diets containing BT at concentrations of 0.4, 0.8, and 1.6 mg/kg. The results indicated that BT-supplemented groups showed increased body weights, weight gain, growth rate, and performance index and reduced feed conversion ratio during the two growth periods compared to control. The best results were obtained with BT 1.6 mg/kg for the antecedent growth metrics. Chicks receiving BT (0.4 mg/kg) had improved renal functions and lower uric acid and creatinine levels than the other groups. Moreover, ALT and AST levels P<0.05 decreased with BT doses compared to the control. BT 1.6 mg/kg produced the best liver function results; the histopathological studies confirmed that BT addition didn't affect the liver and intestine structure. Adding Bacillus toyonensis M44 to the diet formulation improved (P<0.05) lipid profile, immune response, thyroid functions, and gut microflora compared to the control group. Additionally, BT enhanced the chicken meat's juiciness and tenderness characteristics and improved its moisture and protein content; the meat color was also enhanced. Generally, supplementing IR chicken with BT could improve growth performance and blood biochemistry, modulate the gut microflora structure, and enhance the meat quality. [ABSTRACT FROM AUTHOR]

Phytogenic feed additives (PFAs) often referred to as phytobiotics or botanical feed additives, are natural compounds derived from various plants, herbs, spices and other botanical sources. These feed additives are intended to serve a variety of purposes, including an immune system regulator, an antimicrobial, an antimutagenic, an antioxidant and a growth promoter. They are composed of bioactive compounds extracted from plants, including essential oils, polyphenols, terpenoids and flavonoids. They are mostly utilized as substitute antibiotic growth promoters in nonruminant (swine and poultry) livestock production, owing to the prohibition of antibiotic usage in the feed industry. It has been thoroughly examined to ascertain their impact on intestinal health and activity, correlation with animals' effective health and well‐being, productivity, food security and environmental impact. The potential uses of these feed additives depend on the properties of herbs, the comprehension of their principal and secondary components, knowledge of their mechanisms of action, the safety of animals and the products they produce. They are gaining recognition as effective and sustainable tools for promoting animal health and performance while reducing the reliance on antibiotics in nonruminant nutrition. Their natural origins, multifaceted benefits and alignment with consumer preferences make them a valuable addition to modern animal farming process. However, because of their inconsistent effects and inadequate knowledge of the mechanisms of action, their usage as a feed additive has been limited. This review offers a comprehensive assessment of the applications of PFAs as an effective feed supplement in swine and poultry nutrition. In summary, this comprehensive review provides current knowledge, identifies gaps in research and emphasizes the potential of phytogenic additives to foster sustainable and healthier livestock production systems while addressing the global concerns associated with antibiotic use in livestock farming. [ABSTRACT FROM AUTHOR]

ABSTRACT: The main goal of this study was to evaluate the effect of nutraceuticals vs. in-feed antibiotics on performance, blood lipids, antioxidant capacity, cecal microbiota, and organ histomorphology of broiler chickens. A total of 320 one-day-old male broiler chickens were distributed into 5 treatment groups with 8 replicates each. The control group was fed on a basal diet without any additives (NC); the antibiotic group was fed on a basal diet supplemented with 100 mg kg-1 avilamycin (PC); the algal group was fed on a basal diet supplemented with a mixture of Spirulina platensis and Chlorella vulgaris (1.5 g + 1.5 g/kg feed) (SP+CV); the essential oil group was fed with a basal diet containing 300 mg/kg feed rosemary oil (REO); and the probiotics group (a mixture of 1 × 1011 CFU/g Bacillus licheniformis, 1 × 1011 CFU/g Enterococcus facieum, 1 × 1010 CFU/g Lactobacillus acidophilus, and 2 × 108 CFU /g Saccharomyces cerevisiae) was fed with a basal diet supplemented with 0.05% probiotics (PRO). The experiment lasted for 35 d. A beneficial effect of SP+CV and PRO (P < 0.01) was noticed on final body weight, body weight gain, feed conversion ratio, and breast yield. The dietary supplementation with SP+CV, REO, and PRO increased (P < 0.001) broilers' cecal lactic acid bacteria count compared to the control. Lower cecal Clostridium perfringens and Coliform counts (P < 0.001) were noticed in chickens fed the PC and supplemental diets. Malondialdehyde (MDA) concentration was decreased, while glutathione peroxidase (GPx), superoxide dismutase, and catalase enzymes were increased in the breast and thigh meat (P < 0.001) of broiler chickens fed SP+CV, REO, and PRO diets. Dietary SP+CV, REO, and PRO supplementation decreased (P < 0.001) serum total lipids, cholesterol, triglycerides, low-density lipoprotein, and MDA, but increased serum high-density lipoprotein and GPx compared to PC and NC. No pathological lesions were noticed in the liver, kidney, or breast muscle among broilers. The SP+CV, REO, and PRO groups had greater (P < 0.001) intestinal villi height and crypt depth while lower goblet cell densities (P < 0.01) than the control. The present findings suggest that PRO and SP+CV, followed by REO could be suitable alternatives to in-feed antibiotics for enhancing the performance, health, and meat quality of broiler chickens.

Abstract Edwardsiella piscicida causes significant economic losses to the aquaculture industry worldwide. Phage-based biocontrol methods are experiencing a renaissance because of the spread of drug-resistant genes and bacteria resulting from the heavy use of antibiotics. Here, we showed that the novel Edwardsiella phage EPP-1 could achieve comparable efficacy to florfenicol using a zebrafish model of Edwardsiella piscicida infection and could reduce the content of the floR resistance gene in zebrafish excreta. Specifically, phage EPP-1 inhibited bacterial growth in vitro and significantly improved the zebrafish survival rate in vivo (P = 0.0035), achieving an efficacy comparable to that of florfenicol (P = 0.2304). Notably, integrating the results of 16S rRNA sequencing, metagenomic sequencing, and qPCR, although the effects of phage EPP-1 converged with those of florfenicol in terms of the community composition and potential function of the zebrafish gut microbiota, it reduced the floR gene content in zebrafish excreta and aquaculture water. Overall, our study highlights the feasibility and safety of phage therapy for edwardsiellosis control, which has profound implications for the development of antibiotic alternatives to address the antibiotic crisis.

The rise of antibiotic-resistant bacterial infections necessitates alternative therapeutic strategies, such as phage therapy. This study investigates the potential of phage vB_PmuM_CFP3 (CFP3) as a therapeutic agent against avian cholera caused by Pasteurella multocida (P. multocida). Phage CFP3 was isolated from the feces and wastewater of a laying hen farm and underwent comprehensive biological characterization, including host range, lytic activity, and environmental stability. Transmission electron microscopy revealed CFP3′s typical myovirus morphology, with a head diameter of approximately 60 nm and a tail length of about 120 nm. CFP3 demonstrated high stability across a pH range of 4–10 and temperatures of 30–40 °C, making it suitable for oral administration in poultry. The phage exhibited a latent period of about 90 min and an optimal multiplicity of infection (MOI) of 1. Despite its narrow host range, with a lysis rate of 28.2% against avian-derived type A P. multocida, CFP3′s specificity minimizes impact on non-target bacteria. Whole-genome sequencing revealed a 32,696 bp linear double-stranded DNA genome with 46 predicted open reading frames (ORFs) and no tRNA or antibiotic resistance genes, enhancing its safety profile. Phylogenetic analysis indicated a close evolutionary relationship with Haemophilus phages HP1, HP2, and Pasteurella phage F108. While CFP3 shows promise as a precision therapeutic tool, further in vivo studies are required to evaluate its efficacy and safety. Future research should focus on expanding the phage library, optimizing phage mixtures, and exploring synergistic effects with other antimicrobial strategies. This study provides foundational data supporting the development of CFP3 as a viable alternative to antibiotics for controlling avian cholera.

ABSTRACT: Finding effective antibiotic alternatives is crucial to managing the re-emerging health risk of Clostridium perfringens (CP) type A/G–induced avian necrotic enteritis (NE), a disease that has regained prominence in the wake of governmental restrictions on antibiotic use in poultry. Known for its antimicrobial and immunomodulatory effects, the use of bovine lactoferrin (bLF) in chickens is yet to be fully explored. In this study, we hypothesized that bLF can accumulate in the small intestines of healthy chickens through gavage and intramuscular supplementation and serves as a potential antibiotic alternative. Immunohistochemistry located bLF in various layers of the small intestines and ELISA testing confirmed its accumulation. Surprisingly, sham-treated chickens also showed the presence of bLF, prompting a western blotting analysis that dismissed the notion of cross-reactivity between bLF and the avian protein ovotransferrin. Although the significance of the route of administration remains inconclusive, this study supports the hypothesis that bLF is a promising and safe antibiotic alternative with demonstrated resistance to the degradative environment of the chicken intestines. Further studies are needed to determine its beneficial pharmacological effects in CP-infected chickens.

(1) Background: Improving feed efficiency and the vitality of the reproductive system in the late stage of the egg-laying period is of great significance for prolonging the egg-laying cycle and improving egg quality. In the present study, a new flavonoid, which was extracted from kudzu leaf, was chosen to investigate its effects on the productive performance and egg quality of late-laying hens. (2) Methods: A total of 360 500-day-old Hy-Line Brown layer hens were randomly divided into a control treatment group (no KLF supplementation), and groups that received 0.2%, 0.4%, 0.6%, 0.8%, and 1.0% KLF supplement treatments. Each treatment contained 6 replicates, with 10 hens in each replicate. Productive performance metrics, including the daily egg production, egg weight, the number of deformed eggs, egg quality, egg density, egg shape index, eggshell strength, yolk color, and the Haugh unit, were meticulously recorded for each replicate. Furthermore, microbial communities and hypothalamus gene expressions were investigated based on the results of the productive performance and egg quality. (3) Results: KLF supplementation significantly decreased the deformity rate while significantly increasing the eggshell strength in the finishing phase afterward (p < 0.05). Specifically, hens supplemented with 0.6% KLF possessed the lowest deformed egg rate. KLF supplementation significantly increased the relative abundances of Bifidobacterium sp., Blautia sp., Lactococcus sp., and Lactobacillus sp., while significantly decreasing Parasutterella sp. and Escherichia-Shigella sp. (p < 0.05). Furthermore, the interactive analysis showed the hypothalamus gene expression mainly interacted with probiotics, such as Bifidobacterium sp. and Lactobacillus sp., through ribosome biogenesis, nucleocytoplasmic transport, and cAMP signaling pathways. (4) Conclusions: The findings of the present study indicate that KLF supplementation significantly proliferated probiotics, such as Bifidobacterium and Lactobacillus, which may have further interacted with hypothalamus genes, thus decreasing the deformity rate while increasing eggshell strength in the finishing phase.

Antibiotic resistance of pathogens, which is caused by the abuse of in-feed antibiotics, threatens the sustainable development of livestock production. The present study aimed to investigate the efficiency of porcine intestinal antimicrobial peptide (PIAP) as an alternative to in-feed antibiotics in terms of growth performance, intestinal morphology, digestive enzymes and immunity, and microbiota community of the post-weaning piglets. A total of 204 piglets (Duroc × Landrace × Yorkshire, weaned at 28 d age) with a similar body weight of 7.97 ± 1.04 kg were randomly allocated to 4 groups (51 piglets per group): (1) control group: basal diet; (2) AB group: antibiotic, basal diet + chlortetracycline (1000 mg/kg from d 1 to 24; 500 mg/kg from d 25 to 37); (3) P1 group: basal diet + a relatively low dose of PIAP (400 mg/kg from d 1 to 24; 300 mg/kg from d 25 to 37); (4) P2 group, basal diet + a relatively high dose of PIAP (600 mg/kg from d 1 to 24; 500 mg/kg from d 25 to 37). The results showed that serum indicators of hepatocyte damage and relative organ weight were not affected by these treatments (P > 0.05). Compared with the AB treatment, the P1 treatment remarkably decreased jejunal crypt depth and increased jejunal and ileal villus height:crypt depth ratio (P

Like probiotics, postbiotics function without the presence of living cells and are composed of bacteriocins and metabolites that are antibacterial. They improve chicken products and health by reducing acidity in the gut and preventing infectious diseases. A total of 288 one-day-old unsexed broiler birds (Ross308) were divided into sex-specific treatment groups, with each group having four replicates and each replicate containing twelve birds.The treatment groups were as follows: T1 = Standard diet (negative control), T2 = Standard diet + 0.01% doxin200 (positive control), T3 (0.1%) = Standard diet + 0.05% thyme oil + 0.05% postbiotic, T4(0.2%) = Standard diet + 0.1% thyme oil + 0.1% postbiotic, T5(0.3%) = Standard diet + 0.15% thyme oil + 0.15% postbiotic, T6 (0.4%) = Standard diet + 0.2% thyme oil + 0.2% postbiotic.The results showed significantly (P 0.05) in meat color were noticed by feed additives compared to the positive control and stayed within the normal range. Various levels of the combination diet significantly improved tibia bone health, especially at a level of 0.4% (T6). In conclusions, a level of 0.4% combined (0.2% postbiotics+ 0.2% phytobiotics(thyme oil) as viable alternatives to antibiotics in broiler diets.

ABSTRACT: The development of antibiotic-resistant microorganisms prompted the investigation of possible antibiotic substitutes. As a result, the purpose of the current study is to assess the effect of dietary Spirulina platensis extract as an antibiotic alternative on Japanese quail (Coturnix japonica) growth, antioxidant status, blood parameters, and cecal microorganisms. There was a total of 150 Japanese quails used in this study, divided equally among 5 experimental groups (10 birds per group with 3 replicates): group 1 (G1) received a basal diet without any S. platensis extract, group 2 (G2) received a basal diet supplemented with 1 mL S. platensis extract/kg, group 3 (G3) received a basal diet supplemented with 2 mL S. platensis extract/kg, group 4 (G4) received a basal diet supplemented with 3 mL S. platensis extract/kg, and group 5 (G5) received a basal diet supplemented with 4 mL S. platensis extract/kg from d 7 until d 35. The results showed that compared to the control birds in G1, Japanese quail supplemented with 4 mL of S. platensis extract/kg of diet (G5) had significantly better live body weight, body weight gain, feed intake, feed conversion ratio, digestive enzymes, blood parameters, liver and kidney functions, lipid profile, antioxidant profile, immunological parameters, and cecal microorganism's count. There were no significant changes in the percentage of carcasses, liver, and total giblets among all the 5 groups. Only gizzard percentage showed a significant increase in G2 compared to birds in G1. In addition, intestinal pH showed a significant drop in G2 and G5 compared to birds in G1. After cooking the quail meat, the juiciness and tenderness increased as S. platensis extract levels increased, whereas aroma and taste declined slightly as S. platensis extract levels increased. Furthermore, when a high concentration of S. platensis extract was used, the lightness of the meat reduced while its redness and yellowness increased. The disk diffusion assay showed that S. platensis extract had significant antibacterial activity against Staphylococcus aureus, Listeria monocytogenes, Campylobacter jejuni, and Salmonella typhi, with inhibition zones ranging from 16 to 42 mm. This activity may be attributable to the volatile chemicals in S. platensis extract, of which Geosmin and 2-methylisoborneol are the primary components. In the diet of Japanese quails, it is possible to draw the conclusion that the extract of S. platensis can be utilized as a feed additive and as an alternative to antibiotics.

Over the years, the misuse of antibiotics and other drugs in animal production has posed a serious threat to public health and safety. Aiming to improve the health of animal organisms, focusing on the development of the livestock and aquaculture industry, the use of aromatic Chinese medicine has been explored. Aromatic Chinese medicine typically refers to Chinese medicinal herbs and their extracts that contain volatile substances as the main active ingredients and possess an aromatic odor. These substances have antibacterial, anti-inflammatory, and immune-enhancing effects. In recent years, many studies have investigated the potential of aromatic Chinese medicine as substitutes for feed additives. This article reviews the mechanisms of action of aromatic Chinese medicine (mainly essential oils) and the research progress in animal production. It analyzes the relationship between aromatic Chinese medicine and animal health farming and identifies the current issues associated with aromatic Chinese medicine. Additionally, it provides an outlook on the future development prospects, to provide reference opinions for aromatic traditional Chinese medicine application in the health farming and feed industry of livestock, poultry, and aquaculture. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the effects of different doses of the fibrous roots of Polygonatum cyrtonema Hua on the growth performance, slaughter parameters, meat quality, immune function, cytokines, antioxidant capacity, and intestinal morphology of white-feathered broilers. Also, the mechanism to improve immune functions of broilers was explored through network pharmacology and molecular docking technology. A total of 360 AA-white-feathered broilers were randomly divided into six groups (not separated by sex), with six repetitions per group (n = 10). The groups were as follows: basal diet (CON group), basal diet supplemented with 300 mg/kg aureomycin (ANT group), basal diet supplemented with 2%, 3%, and 4% fibrous root raw powder (LD, MD, and HD group), or basal diet supplemented with 3% fibrous root processed powder (PR group), in a 42-day experiment. The dietary inclusion of P. cyrtonema fibrous roots increased slaughter performance (p < 0.05), reduced the fat rate (p < 0.05), improved intestinal morphology (p < 0.05), and improved the immune organ index to varying degrees. It also significantly improved pH reduction, drip loss, and pressure loss of breast muscle and leg muscle (p < 0.05). Furthermore, it significantly improved immune and antioxidant functions including decreased MDA content of serum (p < 0.01), increased GSH-Px content (p < 0.01), IgG, IgA, and C4 contents (p < 0.05), and increased expression of IL-2 and IFN-γ (p < 0.01). Additionally, the mechanism by which fibrous roots improve immune function in broilers was explored using network pharmacology and molecular docking technology. Network pharmacology and molecular docking revealed that flavonoids such as baicalein, 4′,5-Dihydroxyflavone, 5,7-dihydroxy-6,8-dimethyl-3-(4′-hydroxybenzyl)-chroman-4-one, and 5,7-dihydroxy-3-(2′-hydroxy-4′-methoxybenzyl)-6,8-dimethyl-chroman-4-one were key components that enhanced immune function through the MAPK1 and other key targets involved in regulating the MAPK signaling pathway. From the findings, it can be concluded that incorporating P. cyrtonema Hua fibrous root as a natural feed supplement and growth promoter in broiler diets had a positive impact on bird health and performance. [ABSTRACT FROM AUTHOR]

Bacillus spp. have been widely used as probiotic supplements in animal feed as alternatives to antibiotics. In the present study, we screened a Bacillus subtilis strain named BS21 from pig feces. Antimicrobial activities, whole genome mining and UHPLC-MS/MS analysis were used to explore its antimicrobial mechanism. Strain BS21 showed Significant growth inhibition against a variety of animal pathogens, including Escherichia coli, Salmonella enterica Pullorum, Salmonella enterica Typhimurium, Citrobacter rodentium, Shigella flexneri and Staphylococcus aureus. Seven gene clusters involved in antimicrobial biosynthesis of secondary metabolites were encoded by strain BS21 genome, including four non-ribosomal peptides (bacillibactin, fengycin, surfactin and zwittermicin A), one ribosomal peptide (subtilosin A), one dipeptide (bacilysin) and one polyketide (bacillaene). Among them, production of surfactin, fengycin, bacillibactin, bacilysin and bacillaene was detected in the supernatant of B. subtilis strain BS21. To develop the potential application of BS21 in animal production, medium components and fermentation parameters optimization was carried out using response surface methodology (RSM). Production of antimicrobial secondary metabolites of strain BS21 was increased by 43.4%, and the best medium formula after optimization was corn flour 2%, soybean meal 1.7% and NaCl 0.5% with optimum culture parameters of initial pH 7.0, temperature 30°C, rotating speed at 220 rpm for 26 h. Our results suggested that strain BS21 has the potential for large-scale production and application as a potential source of probiotics and alternative to antibiotics for animal production. [ABSTRACT FROM AUTHOR]

Simple Summary: Producing antibiotic-free animal products is one of the urgent global concerns, particularly the emergence of antimicrobial resistance, which has caused several health problems in humans and animals. Inventing natural antibiotic alternatives with multi-biological functions can present a good solution for sustainable animal production without additional load on human and animal health. The integration of biological and industrial technologies, such as microbiology, extraction of phytogenics, and nanotechnology, can aid in innovating new eco-friendly feed additives that can not only act as antibiotic alternatives but may also improve the general health of animals. Therefore, this study was designed to evaluate the physicochemical, antioxidant, and antimicrobial activities of a newly innovated alginate nanoencapsulated synbiotic composite of pomegranate peel phytogenics and multi-probiotic species as a potential feed additive. A synbiotic composed of alginate nanoencapsulated prebiotic (pomegranate peel phytogenics) and multi-species probiotics (Lactococcus lactis, Lactobacillus plantarum, Lactobacillus paracasei, and Saccharomyces cerevisiae) has been developed as a potential eco-friendly alternative to antibiotics. The physicochemical properties of the encapsulated synbiotic were evaluated, and its gastric and storage tolerance, as well as its antioxidant and antimicrobial activity, were tested and compared to that of the non-encapsulated synbiotic (free synbiotic). The results showed that the prebiotic pomegranate peel ethanolic extract contained seven phenolic compounds, with cinnamic being the most abundant (13.26 µL/mL). Sodium alginate-CaCl2 nanocapsules were effective in encapsulating 84.06 ± 1.5% of the prebiotic's phenolic compounds and 98.85 ± 0.57% of the probiotics. The particle size of the alginate-CaCl2 nanoencapsulated synbiotic was 544.5 nm, and the polydispersity index and zeta potential values were 0.593 and −12.3 mV, respectively. Thermogravimetric analysis showed that the alginate-CaCl2 nanoencapsulated synbiotic had high thermal stability at high temperatures, with only 2.31% of its weight being lost within the temperature range of 70–100 °C. The count of viable probiotics in the nanoencapsulated synbiotic was significantly higher than that in the free synbiotic after exposure to gastric acidity and storage for six months at room temperature. The percent inhibition values of the nanoencapsulated synbiotic and ascorbic acid (as a standard antioxidant) were comparable and significantly greater than those of the free synbiotic. The half-maximal inhibitory concentrations (IC50) of the nanoencapsulated synbiotic and ascorbic acid were significantly lower than those of the free synbiotic (3.96 ± 0.42 µg/mL and 4.08 ± 0.79 µg/mL for nanoencapsulated synbiotic and ascorbic acid, respectively, vs. 65.75 ± 2.14 µg/mL for free synbiotic). The nanoencapsulated synbiotic showed the highest significant antimicrobial activity against Escherichia coli (ATCC 8739). Both the nanoencapsulated and free synbiotics showed antimicrobial activity against Staphylococcus aureus (ATCC 6538), similar to that of gentamicin, although the nanoencapsulated synbiotic showed significantly higher inhibition activity compared to the free synbiotic. The nanoencapsulated synbiotic showed antimicrobial activity comparable to gentamicin against Pseudomonas aeruginosa (ATCC 90274), whereas the free synbiotic showed the least antimicrobial activity (p < 0.05). Both synbiotics showed significantly higher antimicrobial activity against Salmonella typhi (ATCC 6539) than gentamicin. Both synbiotics showed antifungal activity against Aspergillus niger and Aspergillus flavus, with a stronger effect observed for the nanoencapsulated synbiotic. However, the activity of both synbiotics was significantly lower than that of fluconazole (an antifungal drug). [ABSTRACT FROM AUTHOR]

Abstract Background The 2017 Veterinary Feed Directive eliminated the use of medically important antibiotics for growth promotion of food animals; thus, alternative growth promoters are highly desirable by food animal producers to enhance animal health and reduce pathogen colonization, including the human foodborne pathogen Salmonella. β(1-3)(1-6)-d-glucan (β-glucan) is a soluble fiber with prebiotic characteristics; it has been shown to modulate immune and intestinal functions that strengthen swine resistance to health challenges such as bacterial infections when supplemented in the diets of growing pigs. The current study evaluated the effects of a β-glucan product on gut microbial community structure as well as Salmonella shedding and intestinal colonization. Results Five-week-old pigs were fed a β-glucan amended diet at 500 g/ton (n = 13) or a non-amended control diet (n = 14) for three weeks, followed by inoculation of the 27 pigs with 1 × 109 colony forming units of Salmonella enterica serovar Typhimurium strain UK1. While remaining on the respective diets, fecal samples collected at 2, 4, 7, and 16 days post-inoculation (dpi) were similar for Salmonella shedding counts between the two diets. At 16 dpi, Salmonella counts were significantly lower in the cecal contents of the β-glucan-fed pigs (P = 0.0339) and a trend towards a reduction was observed in the Peyer’s patches region of the ileum (P = 0.0790) compared to the control pigs. Pigs fed β-glucan for three weeks exhibited an increase in members of the Clostridia class in their fecal microbial communities, and after inoculation with Salmonella, several potentially beneficial microorganisms were enriched in the microbiota of β-glucan-fed pigs (Lactobacillus, Ruminococcaceae, Prevotellaceae, Veillonellaceae, Bifidobacterium and Olsenella). Conclusion Administration of β-glucan altered the swine gut microbiome and reduced Salmonella colonization in the cecal contents.

Antibiotic resistance has become an increasingly common problem in treating infectious diseases caused by pathogenic micro-organisms, and this threat is heightened due to the lack of new antibiotic discoveries since the 1980s. This paper aims to summarise the currently available knowledge on the antimicrobial properties of cholesterol esters and to evaluate the use of cholesterol esters as an alternative to antibiotics. A systematic literature search was conducted in three databases namely Pubmed, Embase, and Web of Science to retrieve articles published between 2000 and 2020 where cholesterol esters were the primary or one of the primary examined molecules as part of research targeting immunity and antimicrobial operations. The findings showed antibacterial properties of cholesterol esters, their synergistic activity with antibiotics, antimicrobial role of cholesterol esters in upper respiratory tract and its diseases in humans, and correlation of cholesterol esters with infection protection in physically active individuals. Overall, there is strong evidence that cholesterol esters have antimicrobial properties. However, the currently pooled information available for cholesterol esters’ antimicrobial properties is not expansive enough to draw a conclusion on its ability to replace existing antibiotics as a treatment for infections and this warrants future investigation.

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Broiler chickens are increasingly kept in large numbers in intensive housing conditions that are stressful, potentially depleting the immune system. With the prohibition of the use of antibiotics in poultry feed spreading worldwide, it is necessary to consider the role of natural feed additives and antibiotic alternatives to stimulate the chickens' immune systems. We review the literature to describe phytogenic feed additives that have immunomodulatory benefits in broilers. We initially review the major active ingredients from plants, particularly flavonoids, resveratrol and humic acid, and then describe the major herbs, spices, and other plants and their byproducts that have immunomodulatory effects. The research reviewed demonstrates the effectiveness of many natural feed additives in improving the avian immune system and therefore broiler health. However, some, and perhaps all, additives have the potential to reduce immunocompetence if given in excessive amounts. Sometimes additives are more effective when given in combination. There is an urgent need to determine tolerance levels and optimum doses for additives deemed most suitable to replace antibiotics in the diet of broiler chickens. Effective replacement is most likely with readily available additives, such as olive oil byproducts, olive leaves and alfalfa. It is concluded that effective replacement of antibiotic function with plant-derived additives will be possible, but that further research is necessary to determine optimum doses. [ABSTRACT FROM AUTHOR]

Simple Summary: Selenium is an essential trace mineral for better performance, meat quality, and health benefits in farm animals. In broiler diets, selenium has been added in inorganic or organic form to maintain the selenium requirement of the chickens. Researchers have studied the effects and applications of both inorganic and organic selenium in broiler nutrition. However, there is a paucity of information pertaining to organic selenium application under coccidiosis conditions. In this study, we evaluated the effect of dietary organic selenium on growth performance, gut health, and tissue selenium concentrations in broiler chickens under coccidiosis conditions. Results indicated that the addition of organic selenized yeast improved the growth performance and enhanced the selenium concentrations in the tissue, regardless of the Eimeria challenge. Therefore, organic selenized yeast supplementation can be recommended to produce selenium-enriched organic broiler chickens. A total of 252 one-day-old Ross broilers were randomly allocated to one of six treatments in a 2 × 3 factorial arrangement with respective Eimeria challenges (non-infection and infection) and three different selenium (Se) diets. Dietary treatments were as follows: (1) Se un-supplemented control (CON), (2) inorganic Se treatment (SS; 0.3 mg/kg as sodium selenite), and (3) organic Se treatment (SY; 0.3 mg/kg as selenized yeast). Six replicate cages were allocated per treatment. Chickens in the respective Eimeria infection groups were infected with an E. acervulina, E. tenella, and E. maxima oocyst mixture (15,000 oocysts/chicken) on day 16. Growth performance was measured on days 16, 22, and 24. On day 22, intestinal samples were collected from randomly selected chickens to evaluate gut lesion scores, antioxidant enzymes, and tight junction gene expression. Blood, breast, and liver samples were collected to analyze the Se concentrations on day 24. Dietary SY supplementation improved (p < 0.05) the growth performance of the chickens regardless of the Eimeria challenge. Moreover, independent of Eimeria infection, Se supplementation elevated (p < 0.05) the heme oxygenase 1 (HMOX-1) expression in jejunal mucosa at 6 days post-infection (dpi). Duodenal junctional adhesion molecule 2 (JAM-2) expression and jejunal occludin (OCLN) were elevated (p < 0.05) with dietary SY supplementation at 6 dpi. Among Se sources, broiler chickens fed with the SY diet showed higher (p < 0.05) Se concentrations in breast muscle and serum on 8 dpi. These results confirmed the beneficial effects of dietary Se and the efficiency of organic Se compared with inorganic Se for growth improvement and muscle Se enrichment in broiler chickens regardless of coccidiosis infection. [ABSTRACT FROM AUTHOR]

Simple Summary: In an era of increasingly complex global trade, continual evolution of production practices, and emerging threats from antibiotic resistance, new strategies for maintaining the health and performance of poultry flocks remain critical along with reducing risk from foodborne pathogens such as Salmonella Enteritidis (SE). Natural feed-additive technologies, often referred to as antibiotic alternatives, may play a key role. In this study, layer pullets were fed a control diet with or without a postbiotic feed additive and subsequently challenged directly or indirectly with SE at 16 weeks of age to evaluate the effect of the postbiotic for preventing or reducing SE colonization loads in birds directly or indirectly exposed to the pathogen. Within birds indirectly exposed to the SE inoculation, the postbiotic was associated with a significant reduction of SE-positive individual birds and their associated SE loads when compared to the control birds 7 days after inoculation, with non-significant yet explorable outcomes after 14 days post-challenge. These data support previous research findings in the literature indicating the postbiotic feed additive may aid in reducing SE in poultry production and may therefore be a candidate component of a comprehensive pre-harvest food-safety management plan. Determining the efficacy of feed-additive technologies utilized as pre-harvest food-safety interventions against Salmonella enterica may be influenced by factors including, but not limited to, mechanism of action, experimental design variables, Salmonella serovar(s), exposure dose, route, or duration in both controlled research and real-world field observations. The purpose of this study was to evaluate the dietary inclusion of a Saccharomyces cerevisiae fermentation-derived postbiotic (SCFP) additive (Diamond V, Original XPC®) on the colonization of cecal and ovarian tissues of commercial pullets directly and indirectly exposed to Salmonella Enteritidis (SE). Four hundred and eighty commercial, day-of-age W-36 chicks were randomly allotted to 60 cages per treatment in two identical BSL-2 isolation rooms (Iowa State University) with four birds per cage and fed control (CON) or treatment (TRT) diets for the duration of study. At 16 weeks, two birds per cage were directly challenged via oral gavage with 1.1 × 109 CFU of a nalidixic-acid-resistant SE strain. The remaining two birds in each cage were thus horizontally exposed to the SE challenge. At 3, 7, and 14 days post-challenge (DPC), 20 cages per group were harvested and sampled for SE prevalence and load. No significant differences were observed between groups for SE prevalence in the ceca or ovary tissues of directly challenged birds. For the indirectly exposed cohort, SE cecal prevalence at 7 DPC was significantly lower for TRT (50.0%) vs. CON (72.5%) (p = 0.037) and, likewise, demonstrated significantly lower mean SE cecal load (1.69 Log10) vs. CON (2.83 Log10) (p = 0.005). At 14 DPC, no significant differences were detected but ~10% fewer birds remained positive in the TRT group vs. CON (p > 0.05). These findings suggest that diets supplemented with SCFP postbiotic may be a useful tool for mitigating SE colonization in horizontally exposed pullets and may support pre-harvest food-safety strategies. [ABSTRACT FROM AUTHOR]

Indigenous Saccharomyces (S.) cerevisiae was cultured under submerged fermentation conditions and ß-glucans were extracted by enzymatic method. The extracted ß-glucans were characterized by FT-IR and their spectra presented peaks at a wavelength of 1021 cm-1. Safety and mutagenicity testing of ß-glucans showed them non-mutagenic and non-toxic up to a concentration of 200 mg/mL. For immunotherapeutic effects against Salmonella (Sal.) typhimurium infection, broiler chicks (n=120) were randomly divided into 4 equal groups viz. A (negative control), B (positive control challenged with Sal. typhimurium; 1.0× 1010 cfu), C (ß-glucans at the dose rate of 50 mg/kg feed + Sal. typhimurium challenge), and D (ß-glucans at the dose rate of 100 mg/kg feed + Sal. typhimurium challenge). Results revealed protective effects of ß-glucans against Sal. typhimurium infection as depicted by mild clinical signs along with minimal/no gross and histopathological lesions. Immunological responses were also higher (P<0.05) in ß-glucans administered birds. ß-glucans also modulated intestinal morphology with improved villi-height and crypt-depth ratio. In conclusion, ß-glucans isolated from indigenous S. cerevisiae conferred protective effects against salmonellosis and therefore can be used successfully in broilers. [ABSTRACT FROM AUTHOR]

Background: The 2017 Veterinary Feed Directive eliminated the use of medically important antibiotics for growth promotion of food animals; thus, alternative growth promoters are highly desirable by food animal producers to enhance animal health and reduce pathogen colonization, including the human foodborne pathogen Salmonella. β(1-3)(1-6)-d-glucan (β-glucan) is a soluble fiber with prebiotic characteristics; it has been shown to modulate immune and intestinal functions that strengthen swine resistance to health challenges such as bacterial infections when supplemented in the diets of growing pigs. The current study evaluated the effects of a β-glucan product on gut microbial community structure as well as Salmonella shedding and intestinal colonization. Results: Five-week-old pigs were fed a β-glucan amended diet at 500 g/ton (n = 13) or a non-amended control diet (n = 14) for three weeks, followed by inoculation of the 27 pigs with 1 × 109 colony forming units of Salmonella enterica serovar Typhimurium strain UK1. While remaining on the respective diets, fecal samples collected at 2, 4, 7, and 16 days post-inoculation (dpi) were similar for Salmonella shedding counts between the two diets. At 16 dpi, Salmonella counts were significantly lower in the cecal contents of the β-glucan-fed pigs (P = 0.0339) and a trend towards a reduction was observed in the Peyer's patches region of the ileum (P = 0.0790) compared to the control pigs. Pigs fed β-glucan for three weeks exhibited an increase in members of the Clostridia class in their fecal microbial communities, and after inoculation with Salmonella, several potentially beneficial microorganisms were enriched in the microbiota of β-glucan-fed pigs (Lactobacillus, Ruminococcaceae, Prevotellaceae, Veillonellaceae, Bifidobacterium and Olsenella). Conclusion: Administration of β-glucan altered the swine gut microbiome and reduced Salmonella colonization in the cecal contents. [ABSTRACT FROM AUTHOR]

Salmonella infection is a major public health issue worldwide. Given the alarming increase in infections with antibiotic-resistant microorganisms and side effects of synthetic antibiotics, there is an increasing interest in medicinal plants as natural alternatives to synthetic drugs to combat antibiotic-resistant microorganisms. The present study investigated the biological properties and health-promoting effects of microencapsulated phenolic compounds of Teucrium polium leaves as a dietary phytobiotic in mice challenged by Salmonella enteritidis. Microcapsules showed a capsulation efficiency of 93.6% with a particle size of 1261.8 nm with antioxidant and antibacterial activities in-vitro. The phytochemical analysis confirmed the presence of various phenolic compounds, i.e., ferulic acid, cinnamic acid, gallic acid, caffeic acid, salicylic acid, catechin, ellagic acid, and chrysin ranged between 121.6 and 975.3 µg/g DW. The microencapsulated phenolics exhibited improvement in the growth, liver function, morphometric parameters of ileum, antioxidant- and inflammation-related gene expression and inhibited the ileal population of S. enteritidis in mice challenged by S. enteritidis infection. The microencapsulated phenolics from T. polium leaves could be a promising phytobiotic approach to combat S. enteritidis infections. [ABSTRACT FROM AUTHOR]

Antibiotic growth promoters have been utilized for long time at subtherapeutic levels as feed supplements in monogastric animal rations. Because of their side-effects such as antibiotic resistance, reduction of beneficial bacteria in the gut, and dysbiosis, it is necessary to look for non-therapeutic alternatives. Probiotics play an important role as the key substitutes to antibacterial agents due to their many beneficial effects on the monogastric animal host. For instance, enhancement of the gut microbiota balance can contribute to improvement of feed utilization efficiency, nutrients absorption, growth rate, and economic profitability of livestock. Probiotics are defined as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host." They are available in diverse forms for use as feed supplements. Their utilization as feed additives assists in good digestion of feed ingredients and hence, making the nutrients available for promoting growth. Immunity can also be enhanced by supplementing probiotics to monogastrics diets. Moreover, probiotics can help in improving major meat quality traits and countering a variety of monogastric animals infectious diseases. A proper selection of the probiotic strains is required in order to confer optimal beneficial effects. The present review focuses on the general functional, safety, and technological screening criteria for selection of ideal Bacillus probiotics as feed supplements as well as their mechanism of action and beneficial effects on monogastric animals for improving production performance and health status. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carvacrol@pro-phytomicelles was fabricated as an alternative to antibiotics. • CAR@pro-phytomicelles could be quickly dissolved into water. • CAR@pro-phytomicelles exhibited strong antiinflammatory and antibacterial activities. • Antibacterial mechanism of CAR@pro-phytomicelles were revealed. • CAR@pro-phytomicelles effectively treated Salmonella enteritidis-infection in mice. In livestock and poultry farming, the use of antibiotics has been abused, which seriously endangers human health. Thus, antibiotic alternatives are urgently needed. The phytochemical carvacrol (CAR) has attracted attention as an antibiotic alternative due to its excellent antibacterial activity and anti-inflammatory activity. However, CAR has high volatility and low water solubility, which seriously affect its antibacterial activity. In this study, two plant-derived small-molecule phytochemicals—glycyrrhizin and rebaudioside A—were selected as nanocarriers for the preparation of a novel solid pro-phytomicelle formulation named as CAR@PP. Using a simple fabrication method, the encapsulation efficiency of CAR reached 98.74 ± 1.14 %. CAR@PP was found to rapidly dissolve in water, resulting in a transparent solution (named as CAR@M) and a 59-fold increase in solubility compared to CAR. CAR@M contained uniform nanoparticles with a particle size, polydispersity index, and zeta potential of 3.52 ± 0.93 nm, 0.17 ± 0.01, and −10.63 ± 0.45 mV, respectively. The in vitro antibacterial activity of CAR@M was evaluated, and the minimum inhibitory concentration for the tested strains was 125–250 μg/ml. The antibacterial mechanisms were found that CAR@M disrupted the bacterial wall and biomembranes and efficiently inhibited bacterial biofilm growth. To the in vivo activity evaluation, treatment with 50 mg/kg CAR@M could effectively improve bacterial liver abscesses, decrease the inflammatory cytokine levels in the liver and cecum, and reduce the bacterial load in the liver and feces in Salmonella enteritidis-infected mice. In conclusion, CAR@PP is a promising alternative to antibiotics in livestock and poultry farming warranting further research. [ABSTRACT FROM AUTHOR]

The widespread use of antibiotics causes the development of antibiotic-resistant bacterial strains, which have a severe impact on poultry productivity and human health. As a result, research is continuing to develop safe natural antibiotic alternatives. In the current study, Bacillus pumilus SA388 was isolated from the chicken feces and confirmed to be a probiotic. The selected strain was tested for its antimutagenic and antioxidant capabilities before being employed as a probiotic food supplement and antibiotic alternative. The effect of B. pumilus SA388 impact on broiler chickens' growth performance, gut microbiome, blood biochemical markers, immunological response, and meat quality was also studied. B. pumilus SA388 showed significant bactericidal activity against Streptococcus pyogenes, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella typhi, and Klebsiella pneumonia. A total of 200 chickens were used in the present study, divided equally among four experimental groups (ten birds per group with 5 replicates): group 1 (control, G1) received a basal diet without B. pumilus SA388, group 2 (G2) received a basal diet supplemented with 0.4 mg/kg of B. pumilus SA388, group 3 (G3) received a basal diet supplemented with 0.8 mg/kg of B. pumilus SA388, and group 4 (G4) received a basal diet supplemented with 1.6 mg/kg of B. pumilus SA388. Over 35 d, the B. pumilus SA388-supplemented groups outperformed the G1 in terms of body weight gain, performance index, and feed conversion ratio, with a preference for the G4 treatment. The levels of alanine aminotransferase (ALT), aspartate transaminase (AST), low-density lipoprotein (LDL), and total cholesterol decreased significantly (P < 0.05) with increasing B. pumilus SA388 dosages compared to the control G1 group. Dietary supplementation of B. pumilus SA388 at 1.6 mg/kg (G4) significantly (P < 0.05) resulted in improved lipid profile, immunological response, thyroid function, and gut microbiota compared to the control group (G1). Compared to the broilers in the control treatment (G1), the addition of B. pumilus SA388 to broilers in G4 significantly (P < 0.05) enhanced juiciness, tenderness, aroma, and taste. Adding B. pumilus SA388 to chicken feed at different doses significantly (P < 0.05) decreased average feed intake while increasing economic and relative efficiency measures. In conclusion, B. pumilus SA388 has been proven to be an effective antibiotic and nutritional supplement. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the effects of different doses of the fibrous roots of Polygonatum cyrtonema Hua on the growth performance, slaughter parameters, meat quality, immune function, cytokines, antioxidant capacity, and intestinal morphology of white-feathered broilers. Also, the mechanism to improve immune functions of broilers was explored through network pharmacology and molecular docking technology. A total of 360 AA-white-feathered broilers were randomly divided into six groups (not separated by sex), with six repetitions per group (n = 10). The groups were as follows: basal diet (CON group), basal diet supplemented with 300 mg/kg aureomycin (ANT group), basal diet supplemented with 2%, 3%, and 4% fibrous root raw powder (LD, MD, and HD group), or basal diet supplemented with 3% fibrous root processed powder (PR group), in a 42-day experiment. The dietary inclusion of P. cyrtonema fibrous roots increased slaughter performance (p < 0.05), reduced the fat rate (p < 0.05), improved intestinal morphology (p < 0.05), and improved the immune organ index to varying degrees. It also significantly improved pH reduction, drip loss, and pressure loss of breast muscle and leg muscle (p < 0.05). Furthermore, it significantly improved immune and antioxidant functions including decreased MDA content of serum (p < 0.01), increased GSH-Px content (p < 0.01), IgG, IgA, and C4 contents (p < 0.05), and increased expression of IL-2 and IFN-γ (p < 0.01). Additionally, the mechanism by which fibrous roots improve immune function in broilers was explored using network pharmacology and molecular docking technology. Network pharmacology and molecular docking revealed that flavonoids such as baicalein, 4′,5-Dihydroxyflavone, 5,7-dihydroxy-6,8-dimethyl-3-(4′-hydroxybenzyl)-chroman-4-one, and 5,7-dihydroxy-3-(2′-hydroxy-4′-methoxybenzyl)-6,8-dimethyl-chroman-4-one were key components that enhanced immune function through the MAPK1 and other key targets involved in regulating the MAPK signaling pathway. From the findings, it can be concluded that incorporating P. cyrtonema Hua fibrous root as a natural feed supplement and growth promoter in broiler diets had a positive impact on bird health and performance.

Restrictions on antibiotic use encourage researchers to seek natural substitutes with the same effects without adverse end effects resulting from antibiotic use. Savory and black pepper have been challenged against Salmonella enteritidis (S. enteritidis) bacterium using the spray dryer method to evaluate growth performance, antioxidant status, immune response, and intestinal health parameters in broilers. In this study, thyme essential oil (50%), savory (25%), peppermint (12.5%), and black pepper seeds (12.5%) were mixed to form essential oil-loaded spherical microcapsules with the particle size of 323 nm and encapsulation efficiency of 96.2%. The main bioactive compounds used in the core of microcapsules included thymol, carvacrol, p-cymene, γ-terpinene, and menthol. Moreover, modified starch (25%) and maltodextrin (55%) were used for the preparation of spherical microcapsules for the enclosed wall with 20% whey protein concentrate. The dietary addition of microcapsules containing essential oil significantly reduced the S. enteritidis population in both ileum and cecum (P

ABSTRACT: With the subsisting restrictions on the use of antibiotics in poultry production, the use of plant extracts has shown some promising antimicrobial capacity similar to antibiotics; however, such capacity is largely dependent on their total polyphenol concentration and profile. Given the emerging antimicrobial potential of red osier dogwood (ROD) extract, the study aimed to investigate the pharmacodynamic effect of ROD extract on the ileal and cecal microbiota of broiler chickens challenged orally with Salmonella Enteritidis (SE). A 21 d 4 × 2 factorial experiment was conducted based on 2 main factors, including diets and SE challenge. A total of 384 one-day-old mixed-sex Cobb-500 broiler chicks were randomly allotted to 4 dietary treatments; Negative control (NC), NC + 0.075 mg trimethoprim-sulfadiazine (TMP/SDZ)/kg of diet, and NC containing either 0.3 or 0.5% ROD extract. On d 1, half of the birds were orally challenged with 0.5 mL of phosphate-buffered saline (Noninfected group) and the remaining half with 0.5 mL of 3.1 × 105 CFU/mL SE (Infected group). Dietary treatments were randomly assigned to 8 replicate cages at 6 birds/cage. On d 21, 10 birds/treatment were euthanized and eviscerated to collect ileal and cecal digesta for gut microbiota analysis. The ileal and cecal microbiota was dominated by phyla Firmicutes, Proteobacteria, and Actinobacteriota. The SE infection decreased (P < 0.05) the relative abundance of Proteobacteria and Actinobacteriota in the ileum and ceca, respectively, however, it increased (P < 0.05) Proteobacteria in the ceca. Both 0.3 and 0.5% ROD extracts (P < 0.05) depressed the relative abundance of Actinobacteriota in the ileum but marginally improved (P < 0.05) it in the ceca compared to the TMP/SDZ treatment. Dietary TMP/SDZ increased (P < 0.05) genus Bifidobacterium at the ileal and cecal segments compared to other treatments. Dietary 0.3 and 0.5% marginally improved (P < 0.05) Bifidobacterium in the ceca and depressed (P < 0.05) Weissella and was comparably similar to TMP/SDZ in the ileum. Regardless of the dietary treatments and SE infection, alpha diversity differed (P < 0.05) between ileal and cecal microbiota. Beta diversity was distinct (P < 0.05) in both ileal and cecal digesta along the SE infection model. Conclusively, both ROD extract levels yielded a pharmacodynamic effect similar to antibiotics on ileal and cecal microbiota.

Simple Summary: Oxidized β-carotene (OxBC), a phytochemical that occurs naturally in plants, including fruits and vegetables, is formed by the spontaneous reaction of β-carotene with ambient oxygen. Synthetic OxBC, obtained by the full oxidation of β-carotene with air, shows considerable promise as a parts-per-million in-feed antimicrobial alternative additive that enhances health and performance in poultry, swine, and ruminant species. OxBC is predominantly composed of β-carotene–oxygen copolymers that have beneficial immune-modulating effects. These effects occur within the innate immune system by priming it to face environmental challenges and by mitigating the inflammatory response in a timely fashion, but without any direct anti-bacterial activity. As well, OxBC modulates but does not stimulate and deplete the animal's energy stores unless directly stress-challenged. Oxidized β-carotene (OxBC), a phytochemical that occurs naturally in plants, is formed by the spontaneous reaction of β-carotene with ambient oxygen. Synthetic OxBC, obtained by full oxidation of β-carotene with air, shows considerable promise as an in-feed antimicrobial alternative additive that enhances health and performance in livestock. OxBC is predominantly composed of β-carotene-oxygen copolymers that have beneficial immune-modulating effects that occur within the innate immune system by priming it to face microbial challenges and by mitigating the inflammatory response. OxBC does not have any direct anti-bacterial activity. Further, unlike traditional immune stimulants, OxBC modulates but does not stimulate and utilize the animal's energy stores unless directly stress-challenged. These immune effects occur by mechanisms distinct from the provitamin A or antioxidant pathways commonly proposed as explanations for β-carotene's actions. Trials in poultry, swine, and dairy cows with low parts-per-million in-feed OxBC supplementation have shown performance benefits over and above those of feeds containing regular vitamin and mineral premixes. Through its ability to enhance immune function, health, and performance, OxBC has demonstrated utility not only as a viable alternative to in-feed antimicrobials but also in its ability to provide tangible health and performance benefits in applications where antimicrobial usage is precluded. [ABSTRACT FROM AUTHOR]

Our objective was to determine effects of feeding lamb's peony byproducts, including stem and leaves (PSL), root (PR), and seeds meal (PSM), on growth, rumen fermentation, slaughter parameters, and meat quality. Sixty‐four lambs (14.0 ± 2.1 kg) were allocated into eight treatments based on BW: no additives (CON), 0.15% aureomycin (CONA), low/high levels of PSL (5%/10% PSL replaced 5%/10% Chinese hay), PR (basal diet with 0.5%/1.0% PR), PSM (5%/10% PSM replaced 5%/10% soybean meal). Growth, digestibility, and rumen fermentation had dose responses whereas slaughter parameters, meat quality, or amino acids indexes were not. Peony byproducts increased DMI (p < 0.001) compared to CON, but higher levels were more advantageous (p = 0.003). However, low levels of peony byproducts decreased the NH3‐N concentration, but increased total volatile fatty acids mole percent more than high levels of that (p < 0.001). All peony byproducts increased dressing percentage (p < 0.05), increased pH and tenderness than CON (p < 0.05). In addition, PSL and PSM improved amino acid profiles of meat compared to CON, and were even better than CONA (p < 0.05). Therefore, peony byproducts not only improved animal growth but also reduced the frequency of antibiotic use in animal feeding. [ABSTRACT FROM AUTHOR]

Escherichia coli infections (including APEC) in broiler chickens are not only a health and economic problem of the flock, but also a significant health threat to poultry meat consumers. The prophylactic and therapeutic effects of the phytobiotic composition on E. coli in broiler chickens were previously described. However, most of the data were related to the reference strains (for both in vitro and in vivo models). Based on the previous studies in human and animals, E. coli strains seem to be multidrug resistance. This, in turn, makes it necessary to develop effective alternative methods of treating this type of infection already at the stage of poultry production. In the present study, the antibacterial activity against various strains of E. coli (including APEC) was assessed for two innovative phytobiotics mixtures: H1, containing thymol, menthol, linalool, trans-anethole, methyl salicylate, 1,8-cineol, and p-cymene; H2, in addition to compounds from H1, containing terpinen-4-ol and γ-terpinene. The unique mixtures of phytobiotics used in the experiment were effective against various strains of E. coli, also against APEC, isolated from broiler chickens from traditional industrial breeding, as well as against those showing colistin resistance. The minimum inhibitory concentration (MIC) values for these unique mixtures were: For H1 1:512 for APEC and non-APEC E. coli strains isolated from day old chicks (DOCs), 1:512 for non-APEC, and 1:1024 for non-APEC isolated from broilers sample. For mixture H2, MIC for APEC from both type of samples (DOCs and broilers) was 1:1024 and for non-APEC (DOCs and broilers) was 1:512. The results suggest that phytobiotic compositions used in this study can be successfully used as a natural alternative to antibiotics in the treatment of E. coli infections in broiler chickens. The promising results may be a crucial point for further analyses in broiler flocks exposed to E. coli infections and where it is necessary to reduce the level of antibiotics or completely eliminate them, thus reducing the risk of foodborne infections. [ABSTRACT FROM AUTHOR]

Simple Summary: It is important to find suitable non-antibiotic alternatives for livestock production. The effects of oxidized β-carotene (OxBC) versus antibiotic growth promoters upon the growth performance of swine were determined through a full 140-day growth cycle in 500 barrows and gilts under commercial production conditions in Vietnam. There were five dietary treatment groups: Control basal diet with no antibiotics or OxBC; Basal diet with antibiotics and no OxBC; Basal diet supplemented with 2, 4, or 8 mg OxBC/kg diet and no antibiotics. OxBC and antibiotics each improved growth rate, feed efficiency, and body weight compared to the unsupplemented control. However, animals receiving 4 and 8 mg/kg OxBC performed better than animals on antibiotics. In Starter pigs (Days 1–28), OxBC reduced the occurrence of diarrhea dose-dependently (2, 4, and 8 mg/kg) and more so than antibiotics. These findings show that oxidized β-carotene can facilitate swine growth and health in the absence of in-feed antibiotics. The effects of oxidized β-carotene (OxBC) were determined upon the growth performance of swine through their full growth cycle under commercial production conditions in Vietnam. Five hundred 28-day-old-weaned barrows and gilts were used in a 140-day complete wean-to-finish feeding trial. Animals were randomized by weight, and each pen contained 20 pigs with the same ratio of barrows to gilts. There were five dietary treatment groups with five replicate pens per treatment: Control basal diet, no antibiotics or OxBC; Basal diet with antibiotics; no OxBC; Basal diet supplemented with 2, 4, or 8 mg OxBC/kg of diet, no antibiotics. Growth performance parameters were calculated for each production stage (Starter: Days 1–28, Grower: Days 29–84, Finisher: Days 85–140) and for the overall study (Days 1–140). OxBC and antibiotics each improved growth rate, feed efficiency, and body weight compared to the unsupplemented control (p < 0.001). Animals receiving 4 and 8 mg/kg OxBC performed better than animals on antibiotics (p < 0.001). In Starter pigs, OxBC reduced the occurrence of diarrhea dose-dependently (2, 4, and 8 mg/kg) and more so than did antibiotics (p < 0.001). These findings support the concept that oxidized β-carotene can facilitate swine growth and health in the absence of in-feed antibiotics. [ABSTRACT FROM AUTHOR]

Antibiotics have been overused and misused for preventive and therapeutic purposes. Specifically, antibiotics are frequently used as growth promoters for improving productivity and performance of food-producing animals such as pigs, cattle, and poultry. The increasing use of antibiotics has been of great concern worldwide due to the emergence of antibiotic resistant bacteria. Food-producing animals are considered reservoirs for antibiotic resistance genes (ARGs) and residual antibiotics that transfer from the farm through the table. The accumulation of residual antibiotics can lead to additional antibiotic resistance in bacteria. Therefore, this review evaluates the risk of carriage and spread of antibiotic resistance through food chain and the potential impact of antibiotic use in food-producing animals on food safety. This review also includes in-depth discussion of promising antibiotic alternatives such as vaccines, immune modulators, phytochemicals, antimicrobial peptides, probiotics, and bacteriophages. [ABSTRACT FROM AUTHOR]

Abstract Background The overuse of antibiotics has led to increased antimicrobial resistance, but plant-derived biological response modifiers represent a potential alternative to these drugs. This investigation examined the immunomodulatory and antibacterial activities of Sida cordifolia (used in ethnomedicinal systems to treat infectious disease). Methods Successive extractions were performed from the roots of these plants in hexane, chloroform, methanol and water. Immunomodulatory activity was determined in a series of experiments measuring the responses of splenocytes, macrophages and an in vivo model of innate immunity (Galleria mellonella). Antibacterial activity was assessed by determining minimum inhibitory/bactericidal concentrations (MIC/MBCs) for various Gram-positive and Gram-negative bacterial strains. Results Immunomodulatory activity was confined to the aqueous extract, and further fractionation and biochemical analysis yielded a highly potent polysaccharide-enriched fraction (SCAF5). SCAF5 is a complex mixture of different polysaccharides with multiple immunomodulatory effects including immune cell proliferation, antibody secretion, phagocytosis, nitric oxide production, and increased expression of pro-inflammatory cytokines. Furthermore, Galleria mellonella pre-treated with SCAF5 produced more haemocytes and were more resistant (P

Glucose oxidase (GOD) could benefit intestinal health and growth performance in animals. However, it is unknown whether GOD can protect piglets against bacterial challenge. This study aimed to evaluate the protective effects of GOD on growth performance, clinical symptoms, serum parameters, and intestinal health in piglets challenged by enterotoxigenic Escherichia coli (ETEC). A total of 44 male weaned piglets around 38 days old were divided into four groups (11 replicates/group): negative control (NC), positive control (PC), CS group (PC piglets +40 g/t colistin sulfate), and GOD group (PC piglets +200 g/t GOD). All piglets except those in NC were challenged with ETEC (E. coli K88) on the 11th day of the experiment. Parameter analysis was performed on the 21st day of the experiment. The results showed that the ETEC challenge elevated (p < 0.05) the rectal temperature and fecal score of piglets at certain timepoints post-challenge, reduced (p < 0.05) serum glucose and IgG levels but increased (p < 0.05) serum alanine aminotransferase activity, as well as caused (p < 0.05) intestinal morphology impairment and inflammation. Supplemental GOD could replace CS to reverse (p < 0.05) the above changes and tended to increase (p = 0.099) average daily gain during the ETEC challenge. Besides, GOD addition reversed ETEC-induced losses (p < 0.05) in several beneficial bacteria (e.g., Lactobacillus salivarius) along with increases (p < 0.05) in certain harmful bacteria (e.g., Enterobacteriaceae and Escherichia/Shigella). Functional prediction of gut microbiota revealed that ETEC-induced upregulations (p < 0.05) of certain pathogenicity-related pathways (e.g., bacterial invasion of epithelial cells and shigellosis) were blocked by GOD addition, which also normalized the observed downregulations (p < 0.05) of bacterial pathways related to the metabolism of sugars, functional amino acids, nucleobases, and bile acids in challenged piglets. Collectively, GOD could be used as a potential antibiotic alternative to improve growth and serum parameters, as well as attenuate clinical symptoms and intestinal disruption in ETECchallenged piglets, which could be associated with its ability to mitigate gut microbiota dysbiosis. Our findings provided evidence for the usage of GOD as an approach to restrict ETEC infection in pigs. [ABSTRACT FROM AUTHOR]