Search

The Homeobox A11 (HOXA11) gene regulates limb skeletal development and muscle growth, thus, it was selected as a candidate gene for bovine carcass traits. In this study, we analyzed the mRNA expression level of HOXA11 in various tissues and cells, and determined the genetic variations in the HOXA11 gene, which might be used as molecular markers for cattle breeding. The mRNA expression profiles of HOXA11 in bovine different tissues showed that HOXA11 was highly expressed in both fat and muscle. The gene expression trend of HOXA11 in myoblasts and adipocytes indicated that HOXA11 might be involved in the differentiation of bovine myoblasts and adipocytes. The data in the Ensembl database showed that there are two putative insertion/deletion (InDel) polymorphisms in the bovine HOXA11 gene. The insertion site (rs515880802) was located in the upstream region (NC_037331.1: g. 68853364-68853365) and named as P1-Ins-4-bp, and the deletion site (rs517582703) was located in the intronic region (NC_037331.1: g. 68859510-68859517) and named as P2-Del-8-bp. These polymorphisms within the HOXA11 gene were identified and genotyped by PCR amplification, agarose gel electrophoresis and DNA sequencing in the 640 Shandong Black Cattle Genetic Resource (SDBCGR) population. Moreover, the mutation frequency was very low after detection, so the mathematical expectation (ME) method was used for detection. Statistical analysis demonstrated that P1-Ins-4-bp was significantly correlated with the beef shoulder (p = 0.012) and tongue root (p = 0.004). Meanwhile, P2-Del-8-bp displayed a significant correlation with the back tendon (p = 0.008), money tendon (p = 2.84 × 10-4), thick flank (p = 0.034), beef shin (p = 9.09 × 10-7), triangle thick flank (p = 0.04), triangle flank (p = 1.00 × 10-6), rump (p = 0.018) and small tenderloin (p = 0.043) in the female SDBCGR population. In summary, these outcomes may provide a new perspective for accelerating the molecular breeding of cattle through marker-assisted selection (MAS) strategies. [ABSTRACT FROM AUTHOR]

Simple Summary: L-carnitine and mannan-oligosaccharides (Bio-Mos) are nutritionally and nutraceutically important additives used as dietary supplements to improve production performance, carcass quality, and feed quality. In this study, the effect of application of L-carnitine and Bio-Mos on selected production parameters and content of basic and mineral components in turkey liver, breast, and thigh muscles and on the physical, morphometric, strength, and mineral composition parameters of femurs was examined. The use of both additives was found to result in a significant increase in the body weight of the birds in the final fattening period. Concurrently, it reduced the amount of fat in the breast muscles and liver. The turkey femurs were also characterized by higher elasticity and breaking strength values. The results indicate the need for further research to determine the optimal doses of L-carnitine and Bio-Mos to be used in poultry nutrition. The study aimed to determine the effect of L-carnitine and Bio-Mos administration on selected production performance, slaughter parameters, elemental and mineral content of liver, breast and thigh muscles, and physical, morphometric, strength and bone mineral composition parameters of turkeys. The experiment was conducted on 360 six-week-old Big-6 turkey females, randomly divided into three groups of 120 birds each (six replicates of 20 birds). The turkeys of the control group were fed standard feed without additives; group II was fed with drinking water, a preparation containing L-carnitine at a dose of 0.83 mL/L, while group III was provided mixed feed with 0.5% Bio-Mos. The addition of L-carnitine and Bio-Mos increased body weight at 16 weeks (p = 0.047) and reduced the proportion of fat in the breast muscle (p = 0.029) and liver (p = 0.027). It also modified the content of some minerals in breast muscle, thigh muscle, liver, and bone. Furthermore, the addition of L-carnitine and Bio-Mos increased bone mass and length and modified the value of selected morphometric and strength parameters. The results indicate a positive effect of the applied feed additives on selected rearing indices and carcass quality while improving the elasticity and fracture toughness of the femur. There is a need for further research to determine optimal doses of L-carnitine and Bio-Mos in poultry nutrition. [ABSTRACT FROM AUTHOR]

Simple Summary: A complete pelleted diet is one of the most popular and effective approaches for feeding livestock because of its contribution to improved flock productivity, low cost, and profitability. However, there are a number of negative effects associated with feeding such diets to livestock which can impact the livestock producer and consumer preferences; these include wool biting, wool eating, odor emission, and the dark color of ruminal tissue. The addition of yucca plays a beneficial role in the nutrition and welfare of livestock, particularly sheep, by reducing the negative effects of feeding complete pelleted diets. Animal diets supplemented with yucca target growth, productivity, and physiological responses. The aim of this study was to improve the quality of complete pelleted diets in order to avoid or mitigate their effects on fecal and urinary odor emission. The results found that supplementing Yucca schidgera extract at a level of 600 mg YS/kg dry matter (DM) in feed improved the fecal and urinary odors of lambs fed on pelleted diets. Sixty male Awassi lambs were used to investigate the effects of dietary Yucca schidgera extract (YS) on the production, fecal and urinary odor emissions, and carcass traits of growing lambs fed complete pellets. Lambs were fed either a complete pelleted diet without yucca (control) or supplemented with 300 or 600 mg YS/kg dry matter (DM) during the 84-day experiment. The weights and feed consumption of the lambs were measured weekly. Blood samples were taken on days 1, 28, 58, and 84, and ruminal fluid samples were collected on day 70. On day 90, the odor emissions from feces and urine were measured. On day 84, 12 lambs were slaughtered for the evaluation of carcass and meat quality. The final values for bodyweight, bodyweight gain, and feed efficiency of lambs fed the YS300 diet were 3.40%, 6.64%, and 6.17%, respectively, higher (p < 0.05) than those fed the YS600 diet. Additionally, the percentage of dressing, myofibril fragmentation index, and ruminal isovalerate percentage of lambs treated with YS600 were higher than those treated with YS300. Compared with the control, the addition of yucca reduced odor emissions from feces and urine. In conclusion, dietary YS300 had no additional benefits on growth rate, feed efficiency, and carcass traits, while dietary YS600 improved fecal and urinary odors. [ABSTRACT FROM AUTHOR]

The Banija spotted pig (BS) is a Croatian autochthonous breed that was officially recognised in 2018. The breed remains threatened with extinction and is on its way to establishing a production cycle that will ensure long-term conservation and sustainability. However, there is a general lack of data on the production traits of BS pigs. The aim of this work was therefore to identify the main fattening, carcass and meat quality traits of the BS pig and to assess the suitability of the breed for sustainable pork production. A total of ten pigs were fattened in a semi-free-range production system up to the average final body weight of 162 ± 17.3 kg. At the end of fattening, the growth, carcass and meat quality traits (pH, meat colour and water holding capacity) of the BS pig were determined and the gross margin based on the production of value-added meat products was calculated and compared with other Croatian local pig breeds. The results, which are to be considered preliminary due to the small data set, show that the fattening and slaughter characteristics of the BS pig are satisfactory and consistent with the characteristics of the breed and the husbandry practices adapted to semi-free-range farming. Furthermore, the meat quality showed suitability for processing for most traits, while the calculation of gross profit confirms the advantage of this breed for a well-rounded production cycle compared with related local pig breeds. [ABSTRACT FROM AUTHOR]

A total of 75 male Awassi (mean BW 23.5 ± 2.0 kg; 3 months old) were used in an 84-day trial to investigate the effects of different feeding regimes on productive performance, carcass characteristics, and meat quality, and the fatty acid profile of growing lambs. Animals were randomly allocated into 3 groups of 25 lambs each. The dietary treatments were as follows: (1) whole barley grain (60%) plus alfalfa hay (40%; GB-AH; the basal diet); (2) a concentrate pelleted diet plus alfalfa hay (CP-AH); and (3) a complete pelleted diet (CPD). Feed intake was measured weekly, and all lambs were weighed every two weeks for an evaluation of the productive parameters. Blood samples were collected from all lambs for the measurement of biochemical and enzymatic variables. At the end of the experiment, 13 lambs from each treatment were slaughtered to evaluate the carcass characteristics, meat quality, and fatty acid composition. The final body weight, body weight gain, average daily gain, and feed efficiency of lambs were lowest (p < 0.05) in lambs on the grain and alfalfa diet compared with the other groups. Feeding lambs either the CP-AH or CPD diets resulted (p < 0.05) in increases in slaughter weight, carcass weights (hot and cold), the percentage of liver and shoulder, carcass length, back fat thickness, and the area of longissimus thoracis muscle compared with those lambs on the GB-AF diet. The proportion of saturated fatty acids in meat was greater (p = 0.04) in lambs fed on the GA-AH diet than in those of lambs fed on the pelleted diets. Lambs on the CP-AH diet had (p < 0.05) the highest ratios of PUFA to SFA and omega 6 to omega 3, and the proportion of omega 6. The atherogenic and thrombogenic indexes were lower (p < 0.05) in the CP-AH group compared with the GB-AH group. In conclusion, the results indicate that feeding growing lambs on concentrate pellets instead of whole barley grain improves the growth rate, traits, meat quality, and fatty acid profile, which have important implications for productivity, efficiency, and profitability in the livestock industry. [ABSTRACT FROM AUTHOR]

The investigation of carcass traits to producemeatwith high efficiency has been in focus on Japanese Black cattle since 1972. To implement a successful breeding program in carcass production, a comprehensive understanding of genetic characteristics and relationships between the traits is of paramount importance. In this study, genomic heritability and genomic correlation between carcass traits, including carcass weight (CW), rib eye area (REA), rib thickness (RT), subcutaneous fat thickness (SFT), yield rate (YI), and beef marbling score (BMS) were estimated using the genomic data of 9,850 Japanese Black cattle (4,142 heifers and 5,708 steers). In addition, we investigated the effect of genetic relatedness degree on the estimation of genetic parameters of carcass traits in sub-populations created based on different GRM-cutoff values. Genome-based restricted maximum likelihood (GREML) analysis was applied to estimate genetic parameters. Using all animal data, the heritability values for carcass traits were estimated as moderate to relatively high magnitude, ranging from 0.338 to 0.509 with standard errors, ranging from 0.014 to 0.015. The genetic correlations were obtained low and negative between SFT and REA [-0.198 (0.034)] and between SFT and BMS [-0.096 (0.033)] traits, and high and negative between SFT and YI [-0.634 (0.022)]. REA trait was genetically highly correlated with YI and BMS [0.811 (0.012) and 0.625 (0.022), respectively]. In sub-populations created based on the genetic-relatedness ceiling, the heritability estimates ranged from 0.212 (0.131) to 0.647 (0.066). At the genetic-relatedness ceiling of 0.15, the correlation values between most traits with low genomic correlation were overestimated while the correlations between the traits with relatively moderate to high correlations, ranging from 0.380 to 0.811, were underestimated. The values were steady at the ceilings of 0.30-0.95 (sample size of 5,443-9,850) for most of the highly correlated traits. The results demonstrated that there is considerable genetic variation and also favorable genomic correlations between carcass traits. Therefore, the genetic improvement for the traits can be simultaneously attained through genomic selection. In addition, we observed that depending on the degree of relationship between individuals and sample size, the genomic heritability and correlation estimates for carcass traits may be different. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that the protein kinase cGMP-dependent 2 (PRKG2) gene is associated with dwarfism in humans, dogo Argentines, and Angus cattle, as well as with height and osteoblastogenesis in humans. Therefore, the PRKG2 gene was used as the target gene to explore whether this gene is associated with several thoracolumbar vertebrae and carcass traits in Dezhou donkeys. Results: In this study, fifteen SNPs were identified by targeted sequencing, all of which were located in introns of the PRKG2 gene. Association analysis illustrated that the g.162153251 G > A, g.162156524 C > T, g.162158453 C > T and, g.162163775 T > G were significantly different from carcass weight. g.162166224 G > A, g.162166654 T > A, g.162167165 C > A, g.162167314 A > C and, g.162172653 G > C were significantly associated with the number of thoracic vertebrae. g.162140112 A > G was significantly associated with the number and the length of lumbar vertebrae, and g.162163775 T > G was significantly associated with the total number of thoracolumbar vertebrae. Conclusion: Overall, the results of this study suggest that PRKG2 gene polymorphism can be used as a molecular marker to breed high-quality Dezhou donkeys. [ABSTRACT FROM AUTHOR]

A fully functional myostatin gene inhibits muscle fiber growth. The objective of the present study was to quantify the association between 21 known myostatin mutations with both calving and carcass traits in 12 cattle breeds. The myostatin genotypes of 32,770 dam-progeny combinations were used in the association analysis of calving dystocia, with the genotypes of 129,803 animals used in the mixed model association analyses of carcass weight, conformation, and fat score. The mixed model included additive genetic, maternal, and permanent environmental effects where appropriate. The mutant genotypes of nt821, Q204X, and F94L were all associated (P < 0.01) with more calving difficulty when present in either the dam or the progeny. The nt821 deletion had the greatest association with calving difficulty when the homozygous deletion was present in either the calf (0.37 points greater calving difficulty score relative to calves carrying no copies of the deletion based on a one to four scale) or the dam (1.30 points greater calving difficulty score relative to dams carrying no copies of the deletion), although the association between the calf’s nt821 genotype and calving difficulty differed depending on the nt821 genotype of the dam. With the exception of nt748_78, nt414, and nt374_51, all other seven segregating myostatin variants were associated (range of allele substitution effect size relative to animals with no copies of the mutant allele) with carcass weight (2.36 kg lighter to 15.56 kg heavier), all 10 segregating variants with conformation (0.15 units less conformed to 2.24 units more conformed assessed on a scale of 1 to 15), and all segregating variants other than E226X with carcass fat (0.23 units less carcass fat cover to 3.85 units more carcass fat cover assessed on a scale of 1 to 15). Of these, the F94L, Q204X, and nt821 mutations generally had the greatest association with all three carcass traits, giving rise to heavier and more conformed carcasses. Despite the antagonistic genetic relationship between calving difficulty and carcass traits, the nt374_51, F94L, and E226X mutations were all associated with improved carcass merit while having minimal expected consequences on calving difficulty. Thus, animals carrying these mutation(s) may have favorable genetic merit for calving difficulty and carcass merit. Furthermore, depending on the dam genotype, a bull with two copies of the nt821 mutation can produce progeny with improved carcass merit while minimizing calving problems. [ABSTRACT FROM AUTHOR]

Hanwoo beef cattle are well known for the flavor and tenderness of their meat. Genetic improvement programs have been extremely successful over the last 40 yr. Recently, genomic selection was initiated in Hanwoo to enhance genetic progress. Routine genomic evaluation based on the single-step breeding value model was implemented in 2020 for all economically important traits. In this study, we tested a single-step marker effect model for the genomic evaluation of four carcass traits, namely, carcass weight (CW), eye muscle area, backfat thickness, and marbling score. In total, 8,023,666 animals with carcass records were jointly evaluated, including 29,965 genotyped animals. To assess the prediction stability of the single-step model, carcass data from the last 4 yr were removed in a forward validation study. The estimated genomic breeding values (GEBV) of the validation animals and other animals were compared between the truncated and full evaluations. A parallel conventional best linear unbiased prediction (BLUP) evaluation with either the full or the truncated dataset was also conducted for comparison with the single-step model. The estimates of the marker effect from the truncated evaluation were highly correlated with those from the full evaluation, ranging from 0.88 to 0.92. The regression coefficients of the estimates of the marker effect for the full and truncated evaluations were close to their expected value of 1, indicating unbiased estimates for all carcass traits. Estimates of the marker effect revealed three chromosomal regions (chromosomes 4, 6, and 14) harboring the major genes for CW in Hanwoo. For validation of cows or steers, the single-step model had a much higher R2 value for the linear regression model than the conventional BLUP model. Based on the regression intercept and slope of the validation, the single-step evaluation was neither inflated nor deflated. For genotyped animals, the estimated GEBV from the full and truncated evaluations were more correlated than the estimated breeding values from the two conventional BLUP evaluations. The single-step model provided a more accurate and stable evaluation over time. [ABSTRACT FROM AUTHOR]

The study determined the effect of introducing 50% of protein from the protein feed pool derived from raw chickpea seeds (CPR) instead of 50% of soybean meal (SBM) in the rearing period from day 22 to 42 on the coefficients of nutrient digestibility, growth performance, selected carcass traits, the hematological and metabolic profile of blood, and the quality of femur bones in male Ross 308 broilers. The study was carried out on 200 22-day-old male Ross 308 broiler chicks (initial weight of 756 g) randomly assigned to two groups (n=100 in each group; 5 cages with 20 birds each). All birds were reared for 42 days. They were fed isonitrogenous and isoenergetic pre-experimental starter diet (day 1 to 21) in crumble form and experimental grower-finisher diets (day 22 to 42) in pelleted form. From rearing day 22, SBM male broilers (grower/finisher) were fed diets with 100% SBM as a protein source. In the diet for the CPR group (grower and finisher), the SBM protein was replaced with 50% of CPR-derived protein. During the grower and finisher stage and between days 22 and 42, the CPR group exhibited significant (P=0.032) reductions in feed intake (FI), higher (P=0.043) slaughter yields, high (P=0.044) % share of breast muscles, and reduced (P=0.003) abdominal fat content. The addition of CPR influenced some blood parameters. The level of total protein, urea, and Mg decreased, whereas the activity of alkaline phosphatase (ALP) and aspartate transaminase (ALT) increased. In the CPR group, an increase in the physical, morphometric, and some strength parameters of the femur (maximum elastic strength – Wy, yielding deformation – dy, bone density index – BDI, and Young's modulus) was observed. Therefore, CPR may be a promising partial substitute of SBM in broiler nutrition, as it enhances production performance and has a beneficial effect on bone quality. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A study was conducted to identify the effects of standardized ileal digestible (SID) branched-chain amino acids (BCAA):lysine (Lys) ratios on the growth performance, plasma nitrogen (N) profile, carcass traits, and economic analysis of growing–finishing pigs fed diets with high corn distillers dried grains with solubles (cDDGS) inclusions. A total of 1,140 pigs (initial body weight [BW] = 28.7 ± 2.0 kg) were housed in 45 pens of 25 or 26 pigs and fed one of five diets in a randomized complete block design. Experimental diets were fed in four phases based on BW. Dietary treatments were a corn–soybean meal (SBM) based diet (PC), a corn–SBM-cDDGS-based diet (NC) with SID BCAA:Lys ratio of PIC (2020) recommendation and NC diets with SID BCAA:Lys ratios targeted for the 73% SID Val:Lys, 60% SID Ile:Lys, and 144% SID Leu:Lys during the growing phases (25 to 80 kg, Grow), targeted for the 78% SID Val:Lys, 70% SID Ile:Lys, and 160% to 170% SID Leu:Lys during the finishing phases (80 to 120 kg, finish), and both during the growing and finishing phases (Grow–Finish). One pig from each pen was bled at the end of 7 and 13 wk. After the 11-wk-feeding trial, pigs were sent to a commercial abattoir to investigate carcass traits. Pigs fed the Finish diet had a greater overall average daily gain (P < 0.05) than pigs fed the other cDDGS diets. Dietary treatments did not affect the hot carcass weight. However, feeding the Finish diet increased (P < 0.05) the iodine value of pork belly samples and decreased (P < 0.05) carcass yield. The plasma urea nitrogen (PUN) concentration at the end of the growing phase and plasma concentrations of Leu and Val were greater (P < 0.05) in pigs fed the Finish diet compared to the other cDDGS diets. Feeding pigs the cDDGS diets with different BCAA:Lys ratios had no difference in income over feed cost and income over feed and facility costs compared to the corn–SBM diet. Therefore, feeding pigs cDDGS diets with SID BCAA:Lys ratios adjusted for the previously determined finishing phase (from 80 to 120 kg of BW) recommendations by SBM inclusion supported growth performance and economic benefits equal to the corn–SBM diet. [ABSTRACT FROM AUTHOR]

The mature peptide of growth differentiation factor 11 (GDF11) in Bos taurus breeds, shares 90% amino acid sequence similarity to myostatin (MSTN), where loss-of-function mutations result in muscular hyperplasia causing a phenotype known as double-muscling. Mutations in the MSTN coding sequence increase muscle mass and reduce fat and bone tissues, but also confer poor fertility, reduced stress tolerance, and increased calf mortality. GDF11 influences skeletal muscle development in mice, and muscular atrophy can be induced by exogenous GDF11 treatment. To date, there are no reports of GDF11's role in bovine carcass traits. To determine associations between GDF11 and carcass quality in beef cattle, bovine GDF11 was examined in crossbred Canadian beef cattle populations during finishing. Few coding variants were found in this functionally important gene, but an upstream variant c.1-1951C > T (rs136619751) with a minor allele frequency of 0.31 was identified and further genotyped in two separate populations of crossbred steers (n  = 415 and 450). CC animals had lower backfat thickness, marbling percentage, and yield score than CT or TT animals (P <  0.001 and < 0.05). These data suggest a role of GDF11 in carcass quality in beef cattle and may provide a selection tool to improve carcass traits in cattle. [ABSTRACT FROM AUTHOR]

Simple Summary: With the ban on using antibiotics as animal growth promoters in many countries, developing alternative growth promoters is of urgent need. In this study, we investigated the growth-promoting efficacy of a traditional Chinese medicine (TCM) formula Zhenqi granules (ZQ) in pigs. We show that ZQ has a significant growth-promoting effect in pigs, especially during the finishing stage. To further explore the possible mechanisms of growth promotion, transcriptomics analysis with liver and skeletal muscle tissues are performed that reveals that genes involved in collagen biosynthesis and lipid biosynthetic processes are differentially expressed in the pigs administrated with ZQ. We report for the first time that a TCM formula ZQ has significant growth promotion efficacy in pigs and reveals that it may promote animal growth by regulating skeletal myogenesis and fat deposition. Developing nonantibiotic livestock growth promoters attracts intensive interest in the post-antibiotic era. In this study, we investigated the growth-promoting efficacy of Zhenqi granules (ZQ) in pigs and further explored the possible mechanisms by transcriptomics analysis. Weaned piglets (52 days old with an average body weight of 17.92 kg) were fed with diets supplemented with different doses of ZQ (0 g/kg, 1 g/kg, and 2 g/kg) for 30 days and continued observations for an additional 32 days after removing ZQ from the diets. Compared with the control group, the average daily gain, carcass weight, average back fat thickness, and fat meat percentage of the group supplemented with 1 g/kg of ZQ showed a significant increase, and the feed/gain ratio was lower. The group supplemented with 2 g/kg of ZQ also showed a significant increase in average daily gain and average backfat thickness. A transcriptomics analysis revealed that the supplementation of ZQ at 1 g/kg upregulated the expression of genes related to collagen biosynthesis and lipid biosynthesis in skeletal muscle and liver. This effect was primarily through upregulating the mRNA levels of structural proteins and lipid-related enzymes. This study demonstrates the growth-promoting efficacy of ZQ and provides some insights of the mechanism of growth promotion. [ABSTRACT FROM AUTHOR]

The aim of this study was to find significant genomic regions associated with carcass traits in Hanwoo cattle and to compare the benefit of using additional information from non‐genotyped animals. Imputed whole‐genome sequence data were used along with phenotypic data on 13 715 genotyped animals as well as phenotypes of 440 284 non‐genotyped animals that were offspring of 454 genotyped sires. For carcass weight, 15 083 SNPs in 33 QTL regions and 313 candidate genes were identified. We found 410 SNPs in 17 QTL regions containing 122 candidate genes for back fat thickness. In total, 656 SNPs in 19 QTLs with 137 candidate genes for eye muscle area and 79 SNPs in 12 QTL regions with 77 candidate genes were identified for marbling score. The most important candidate genes included ZFAT, TG, PLAG1, CHCHD7, and TOX for carcass weight and eye muscle area, NOG for back fat thickness, and EVOVL5 for marbling score. This study showed that the use of phenotypic records on non‐genotyped progeny along with imputed whole‐genome sequence data increased the power of detecting new significant genomic regions. [ABSTRACT FROM AUTHOR]

We evaluated the fects of different levels of dietary silver nanoparticle (AgNP) powder on performance, intestinal microflora, carcass traits and blood parameters of broiler chickens. Three hundred seven-day-old Ross broiler chicks were randomly divided into five groups, each group replicated three times with 20 birds per replication. Chickens were fed the basal diet with 2.5, 5, 10 and 20 mg AgNPs per kg feed. Dietary inclusion of AgNPs improved the final body weight, cumulative weight gain and feed conversion ratio. The best broiler performance, carcass traits, and relative organ weights were observed in the group supplemented with 2.5 ppm AgNPs. Increasing the AgNP dose resulted in a significant decrease in the caecal lactose positive and enterococci bacteria populations, while lactobacilli counts were numerically increased. The silver residues in the breast and thigh muscle significantly increased (p <.05) in a dose-dependent manner. Dietary inclusion of AgNPs induced dose-dependent lesions in liver, kidney, spleen and duodenum tissues involving degeneration, necrosis, mononuclear infiltration and focal aggregation of inflammatory cells. In conclusion, despite its potential positive impacts on growth performance, carcass traits and caecal microbial population diversity at a dose of 2.5 ppm, dietary inclusion of AgNPs had the following negative effects on broilers: 1) silver residues in breast and thigh muscle, which may result in AgNPs transmission to consumers, and 2) cytotoxicity in intestinal, liver, spleen and kidney cells in a dose-dependent manner. Therefore, we suggest the use of lower doses of AgNPs (< 2.5 ppm diet) in poultry production in the future studies. Dietary inclusion of silver nanoparticles (AgNPs) in broiler diets more than 2.5 mg/kg diets had many negative effects represented by accumulation of silver residue in broiler meat and the possibility of transmission of nanosilver to consumers. AgNPs had a cytotoxic effect on intestine, liver, spleen and kidney cells in a dose-dependent manner in broilers and might be harmful to chicken and human health. Therefore, we do not recommend using AgNPs as a dietary growth promotor or antibacterial agent in broiler diets and their use and marketing should be controlled and restricted. [ABSTRACT FROM AUTHOR]

Objective: This study was performed to determine the apparent metabolizable energy (AMEn) content of tannin-free red/bronze, white/tan and U.S. No. 2 varieties of grain sorghum for feeding Japanese quail and validate their nutrient profile by evaluating effects on performance and carcass traits with full-substitution of corn. Methods: Experiment 1 determined the AMEn content of red/bronze, white/tan, and U.S. No. 2 grain sorghum varieties fed to mixed-sex Japanese quail (Coturnix japonica) (n = 314) at 3 and 6-weeks of age. Analyses were based on a 2×4 factorial treatment design with age and grain types defining the treatments, and a randomized complete block experiment design with cage and trials defining the block. AMEn values were validated by evaluating the performance and carcass traits of Japanese quail (n = 644) from 1 to 40 days of age in Experiment 2 with birds were fed 1 of 4 complete diets. Statistical analyses were conducted on performance data and select individual carcass trait measurements. Results: Determined AMEn values at 3-weeks of age were 3,524±122.03 (red/bronze), 3,252± 122.03 (white/tan), and 3,039±123.44 (U.S. No. 2) kcal/kg. At 6-weeks of age, determined AMEn were 3,373±297.35 (red/bronze), 3,279±297.35 (white/tan), and 2,966±298.64 (U.S. No. 2) kcal/kg. Carcass traits showed live body weight (p = 0.0409) and hot carcass weight (p = 0.0234) were greatest in U.S. No. 2; however, carcass yield (p<0.0001) was lowest. No significant differences were observed among treatments for feed intake, feed conversion ratio, breast weight and breast yield (p>0.05). Conclusion: These studies demonstrated that tannin-free grain sorghum varieties may be a potential alternative to corn in quail diets while maintaining growth performance and carcass parameters. [ABSTRACT FROM AUTHOR]

The slaughter and carcass features of four breeds named Limousin (LI), Charolais (CH), Angus (AN), and Hereford (HE) were examined. Nine calves from each breed were slaughtered at an average age of 18.5 months. The animals were weighed before slaughter, and the slaughter weights as well as some body measurements of the animals were recorded. The dismemberment of the carcasses was performed after a resting period of 24 h at + 4 °C. The slaughter weights were 581.89, 590.72, 577.67, and 610.89 kg, respectively. Chilled carcass weights were 348.26, 346.91, 327.60, and 338.10 kg, respectively, with no significant differences among breeds. Dressing percentages were 59.89, 58.75, 56.71, and 55.33%, and the valuable meat ratios were 27.89, 27.66, 24.45, and 24.32%, respectively. Carcass bone ratios were 13.89, 14.17, 14.64, and 14.61%, respectively. The longissimus muscle areas (LMA) were 97.46, 102.29, 81.05, and 83.93 cm2, and the subcutaneous fat thickness was 0.38, 0.43, 1.00, and 1.32 cm, respectively. Significant differences were observed among breeds in terms of these characteristics. Carcass weight was highest in LI, and LI and CH breeds had higher carcass yields than the other two breeds. Although HE had the highest slaughter weight, it showed the lowest carcass yield. Whilst more meat was obtained from LI and CH, the highest fat and bone ratios were determined in HE and AN. [ABSTRACT FROM AUTHOR]

The use of rapeseed as a source of protein in broiler chicken diets has been highlighted. However, there are inconsistent findings on the performance data of broiler chickens fed rapeseed meal (RSM). Therefore, this meta-analysis aimed to resolve the inconsistent findings on the effect of RSM on growth performance, carcass characteristics, internal organs, and intestinal histomorphology of broiler chickens, identify knowledge gaps and create new insights using published data. Fourteen studies on the topic were identified via a systematic search performed on bibliographic databases, and the data generated was analysed using OpenMEE software. A random-effects model was used, and effect sizes were presented as standardised mean difference (SMD) at a 95% confidence interval (CI). Sources of heterogeneity were evaluated using broiler strains, inclusion levels, processing methods, rearing phases and sex as moderators. In comparison with the controls, the results showed that RSM decreased feed intake (SMD = -0.29; 95% Cl: -0.41, -0.18; p < 0.001), average daily gain (SMD = -0.48; 95% Cl: -0.63, -0.32; p < 0.001), and liver weight (SMD = 1.24; 95% Cl: 0.78, 1.71; p < 0.001), but had no effect on feed conversion ratio (SMD = 0.10; 95% Cl: -0.05, 0.23; p = 0.19). Likewise, broiler chickens fed RSM had significantly reduced carcass yield, weights of thigh, abdominal fat and heart when compared with the control. Results indicate that duodenum villus height (DVH) and jejunum villus height (JVH)/crypt depth (CD) ratios were improved in broiler chickens fed RSM. Meta-regression revealed that the analysed moderators are significant predictors of feed intake, average daily gain and feed conversion ratio in broiler chickens. In conclusion, dietary RSM negatively influenced growth performance, liver weight and carcass characteristics in broiler chickens, but improved aspects of intestinal histomorphology traits. Therefore, innovative research on processing methods that will improve the feeding value of rapeseed meal in broiler chickens is recommended., (© 2024 The Author(s). Journal of Animal Physiology and Animal Nutrition published by Wiley‐VCH GmbH.)

Artificial rearing (AR) of lambs is nowadays a common practice in Mediterranean dairy sheep production systems to enhance the milk available for cheese or yoghurt manufacturing. The sufficient growth of lambs in an AR system is vital for the economic success of dairy sheep farms. However, AR is often associated with negative impacts on the performance and physiology of lambs. Greece is one of the major producers of ovine milk; nevertheless, data concerning the effects of artificial rearing in lambs of Greek autochthonous breeds are not available. Therefore, the present study aimed to examine the influence of artificial rearing on growth performance, thyroid hormone levels, locomotor activity, carcass traits and meat quality characteristics in lambs of the Chios breed, which is one of the most well-known Greek dairy sheep breeds. Twenty-one singleton male lambs were assigned into two feeding regimes; natural rearing NR ( n = 11) and AR ( n = 10). The lambs' behavior was continuously videotaped until weaning, and their standing percentage was recorded as an activity index. Blood samples were collected from the jugular vein of lambs on days 3, 10, 17 and 40 after birth to assess thyroid hormone levels. The body weight of lambs was also recorded weekly. At the age of 45 days, lambs were fasted for 12 h, weighed and slaughtered. The weights of the carcass and internal organs were measured, while samples of the longissimus dorsi muscle were used for the determination of meat pH, color, water holding capacity, shear force and oxidative stability values. As indicated, body weight (kg) at birth was greater in NR vs. AR group and this difference was maintained till day 35 ( p < 0.05), although body gain (kg) was generally not significantly different between NR and AR lambs, with the exception of the first week, when NR showed a greater value compared with the AR lambs ( p < 0.001). On day 42, no significant differences between lamb groups for body weight were observed. Levels for triiodothyronine (T3), thyroxine (T4) and the free form of T3 (FT3) were greater, whereas the standing percentage was lower in NR compared with AR lambs ( p < 0.05). The feeding regime of lambs did not affect carcass traits, internal organ and fat tissue weights, except for cold carcass yield which was greater in AR vs. NR lambs. No significant differences were observed between the two lamb groups in meat quality characteristics, such as pH, color, water holding capacity and shear force values, although MDA content was decreased in AR lambs indicating an improved oxidative stability. In conclusion, artificial rearing appears to be a feasible strategy for Chios lamb meat production, since it does not negatively influence carcass traits and meat quality characteristics, while a positive effect in meat oxidative stability is observed.

Meat rabbits are a small herbivorous livestock and have been popularly raised in China for producing high-quality meat. Therefore, it is economically important to genetically improve both carcass performance and meat quality in meat rabbits. However, we still know less about the underlying candidate genes that may determine phenotypic variation on carcass and meat traits of meat rabbits. The main objective of this study was to identify candidate genes whose mRNA expression levels may be significantly involved in regulating carcass and meat traits of meat rabbits based on the transcriptome-wide association studies (TWAS). Five carcass traits of the carcass weight (CW), dressing out percentage (DP), cut weight of hind legs (LW), weight ratio of cut hind legs to carcass (RLW), and weight of visceral and interscapular fat (WF), as well as two meat traits of the drip loss (DL) and cooking loss (CL) were phenotyped in a F1 crossbred population ( N  = 119) between Zika rabbits and Sichuan White rabbits. The effects of mRNA expression levels of a total of 10,288 genome-wide genes on these seven traits were statistically estimated using the mixed linear model, in which the polygenic background effects were accounted for. Our results revealed two candidate genes ( RDH5 and MTARC2 ) that were statistically significantly associated with LW trait (the adjusted p values <0.05), whereas no gene reached the statistically significant threshold for all the remaining six traits. Because of the relatively small sample size analyzed, we alternatively selected 20 candidate genes with the lowest p values for every trait and subjected them to functional enrichment analyses, which identified three Gene Ontology (GO) terms that were significantly enriched by the candidate genes of CW and RLW traits. In conclusion, this study used TWAS approach to successfully reveal several candidate genes whose mRNA expression levels may be involved in regulating carcass and meat traits in meat rabbits, which are helpful to explore the underlying molecular mechanism in the future studies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 He, Tian, Kang, Wang, Jia, Sun, Lai and Chen.)

Objective: The improvement of carcass traits is essential for the Hanwoo industry because of the Hanwoo grade determination system, and genome-wide association study (GWAS) analysis is an instrumental tool for identifying the genetic factors that impact these traits. While GWAS analysis utilizing family data offers advantages in minimizing genetic bias, research on family-based GWAS in Hanwoo is currently lacking., Methods: This study classified Group A using both parental and offspring genetic information, and Group B based solely on offspring genetic information, to compare GWAS analysis results of Hanwoo carcass traits., Results: A total of 16 significant single nucleotide polymorphism (SNP) markers were identified in Group A, comprising 7 for carcass weight (CWT), 3 for back fat thickness (BFT), and 6 for marbling score (MS). In Group B, 7 significant SNP markers were identified, including 3 for CWT, 1 for eye muscle area, 1 for BFT, and 2 for MS. Functional annotation analysis revealed only one common function related to carcass traits between the groups, while protein-protein interaction analysis indicated more gene interactions in Group A. The reliability of estimated values for common SNP markers identified between the groups was higher in Group A., Conclusion: GWAS analysis utilizing parental genetic information holds greater potential for application, owing to its higher reliability of estimated values and the ability to explore numerous candidate genes.

Poultry meat, particularly Peking ducks, holds a significant global market share, prized for their high meat yield and fat content. However, understanding of the molecular genetic mechanisms influencing carcass yield in ducks is limited. This research aims to use genome-wide association analysis to uncover single-nucleotide polymorphisms influencing carcass yield in Peking ducks, followed by identifying candidate genes linked to carcass traits. In this study, we analyzed seven traits of 643 Peking ducks at age 42 days and identified novel loci associated with these traits. A total of 35 significant loci were detected, with eight SNPs reaching genome-wide significance. KIF20B, AGBL5, SGSM1, MRO, PLAG1, XKR4, and TGS1 were considered as important candidate genes influencing carcass yield in ducks. This study adds to the list of genes affecting Peking duck body traits, aiding marker-assisted breeding and enhancing economic yield., (© 2024 Stichting International Foundation for Animal Genetics.)

This study was conducted to evaluate the relationship among market weight, slaughter age, yield grade, and primal cut yield in Hanwoo. A total of 403 Hanwoo (Korean native cattle) was assessed for carcass traits such as carcass cold weight, backfat thickness, ribeye area, dressing percentage, yield index, and marbling score. The production yield of the individual major primal cuts of Hanwoo beef was also measured. Carcass cold weight, ribeye area, and backfat thickness, which affect meat quality increased with increased market weight (p < 0.05). The production yield of the ten major primal cuts also increased with increased market weight (p < 0.05). In terms of slaughter age, carcass cold weight, ribeye area, and backfat thickness all increased from 25 months to 28–29 months, and the production yield of all prime cuts also increased with increasing slaughter age. According to the meat yield grade, carcass cold weight and backfat thickness increased from grade A to grade C, although the ribeye area was not affected. The combined findings of the study suggest that slaughtering Hanwoo at the weight of 651–700 kg and 701–750 and age of 28.23 and 29.83 months could be desirable to achieve the best quality and quantity grade of Hanwoo beef. However, the positive correlation of carcass cold weight and backfat thickness, and the negative correlation of the yield index according to primal cuts yield indicated that it is necessary to couple the slaughtering management of cattle with improved genetic and breeding method of Hanwoo to increase the production yield of the major prime cuts of Hanwoo beef.

The investigation of carcass traits to produce meat with high efficiency has been in focus on Japanese Black cattle since 1972. To implement a successful breeding program in carcass production, a comprehensive understanding of genetic characteristics and relationships between the traits is of paramount importance. In this study, genomic heritability and genomic correlation between carcass traits, including carcass weight (CW), rib eye area (REA), rib thickness (RT), subcutaneous fat thickness (SFT), yield rate (YI), and beef marbling score (BMS) were estimated using the genomic data of 9,850 Japanese Black cattle (4,142 heifers and 5,708 steers). In addition, we investigated the effect of genetic relatedness degree on the estimation of genetic parameters of carcass traits in sub-populations created based on different GRM-cutoff values. Genome-based restricted maximum likelihood (GREML) analysis was applied to estimate genetic parameters. Using all animal data, the heritability values for carcass traits were estimated as moderate to relatively high magnitude, ranging from 0.338 to 0.509 with standard errors, ranging from 0.014 to 0.015. The genetic correlations were obtained low and negative between SFT and REA [−0.198 (0.034)] and between SFT and BMS [−0.096 (0.033)] traits, and high and negative between SFT and YI [−0.634 (0.022)]. REA trait was genetically highly correlated with YI and BMS [0.811 (0.012) and 0.625 (0.022), respectively]. In sub-populations created based on the genetic-relatedness ceiling, the heritability estimates ranged from 0.212 (0.131) to 0.647 (0.066). At the genetic-relatedness ceiling of 0.15, the correlation values between most traits with low genomic correlation were overestimated while the correlations between the traits with relatively moderate to high correlations, ranging from 0.380 to 0.811, were underestimated. The values were steady at the ceilings of 0.30–0.95 (sample size of 5,443–9,850) for most of the highly correlated traits. The results demonstrated that there is considerable genetic variation and also favorable genomic correlations between carcass traits. Therefore, the genetic improvement for the traits can be simultaneously attained through genomic selection. In addition, we observed that depending on the degree of relationship between individuals and sample size, the genomic heritability and correlation estimates for carcass traits may be different.

Thirty-two weaned male Barbari kids (av. age, 144.65 days; weight, 9.43±0.24 kg), reared under intensive system of feeding, were divided equally into four groups (T1, T2, T3 and T4) to investigate the effect of supplementation of different levels of concentrate mixture on voluntary intake, growth performance, carcass traits and quality. All kids were fed with Bengal gram straw ad lib. + green fodder ad lib. as basal ration and supplemented with barley grain @ 0.7% of body weight in T1 and concentrate mixture @ 0.7, 1.4, and 2.1% of body weight in T2, T3, and T4, respectively. Dry Matter Intake (DMI, g)/kg W0.75 increased significantly in T1 and T4 than T2 and T3. Average daily weight gain (ADG) (g/d/kid) was enhanced significantly with each gradual increase in concentrate level. Slaughter weight and empty body weight were greatest in T4 compared with other treatments. Significantly greater dressing percentage and yield of separated lean meat was observed in kids under T3 and T4 than other two groups. But, meat:bone ratio and separated carcass fat yield was significantly higher only in kids under T4. Meat protein content (%) increased in T2, T3, and T4 as compared to control T1. Meat fat content increased linearly due to a gradual increase in the level of concentrate mixture supplementation to the finisher kids. Whereas, meat moisture and ash per cent remained unaltered due to different levels of concentrate supplementation to kids. Therefore, it may be concluded that supplementation of concentrate mixture @ 2.1% of the body weight in the roughage-based diet increased DMI in finisher Barbari kids with greater energy and protein values, which attributed to enhanced ADG in such kids by 408.3% over the control (supplemented with barley grain only), and also improved feed conversion ratio, carcass yield, carcass traits, and meat quality.

The effects of different dietary n-6/n-3 polyunsaturated fatty acids (PUFA) ratios and gender on key carcass traits, as well as the nutritional and technological quality of lipids in medium–heavy pig tissues have been poorly studied. To investigate the subject, 24 Large White, barrows and gilts, evenly divided into two groups of 12, were fed from 80 kg of live-weight (LW) until slaughter at 150 kg LW, either a high (9.7:1) (HPR) or low (1.4:1) (LPR) dietary n-6/n-3 PUFA ratio. On individual samples of longissimus thoracis muscle (LTM), subcutaneous (SF) and perirenal (PF) adipose tissues (ATs), the fatty acid (FA) composition was determined by gas chromatography, and lipid nutritional indices (LNIs) were calculated. The oxidative stability of meat was evaluated by determining the malondialdehyde content on raw and cooked (24 h postmortem) and refrigerated (8 days postmortem) LTM samples. The carcass traits did not vary between genders and diets. The LPR group showed a higher n-3 PUFA level and a lower n-6/n-3 PUFA ratio in all the tissues examined and better LNI, especially in the ATs. Diet did not affect the oxidative stability of meat. Gender did not influence the n-6/n-3 PUFA ratio, while barrows showed improvements in some LNI in ATs. Reducing the n-6/n-3 ratio in the diet of growing–finishing medium–heavy pigs improved the FA profile in all tissues and most LNI in ATs without impairing the oxidative stability of meat.

This study was conducted to determine the slaughter and carcass traits and the effects of sex on these traits of native geese reared in Muş. A total of 41 geese (17 male and 24 female) which were 8-10 months of age were used. The means of slaughter weight, cold carcass weight, head weight, feet weight, heart weight, liver weight, gizzard weight and spleen weight were 3968.6, 2678.7, 172.1, 131.4, 38.6, 69.3, 144.3, 2.28 g for males, and 3212.2, 2047.6, 138.5, 113.0, 24.8, 76.3, 142.2, 2.18 g for females respectively. Significant phenotypic correlation coefficients were calculated between slaughter weight and feather, head and feet weights in both sex groups and between carcass weight and feather and feet weight in only male geese. Slaughter weight was positively related with heart and gizzard weights in males, carcass weight was negatively related with liver weight in females (r= -0.45). In conclusion, the results of obtained in this study indicated that meat yield was low of the geese reared extensively in Muş province, the slaughter and carcass trait and the phenotypic correlations among of this traits were affected by sex.

The Chuanzang black (CB) pig is a new crossbred between Chinese local breeds and modern breeds. Here, we investigated the growth performance, plasma indexes, carcass traits, and meat quality characteristics of conventional DLY (Duroc × Landrace × Yorkshire) crossbreed and CB pigs. The LC-MS/MS-based metabolomics of pork from DLY and CB pigs, as well as the relationship between the changes in the metabolic spectrum and meat quality, were analyzed. In this study, CB pigs presented lower final body weight, average daily gain, carcass weight, and eye muscle area than DLY pigs (p ˂ 0.05). Conversely, the ratio of feed to gain, marbling score, and meat color score of longissimus dorsi (LD) were higher in CB than DLY pigs (p ˂ 0.05). Moreover, psoas major (PM) showed a higher meat color score and a lower cooking loss in CB than DLY pigs (p ˂ 0.05). Interestingly, CB pigs showed lower myofiber diameter and area but higher myofiber density than DLY pigs (p ˂ 0.05). Furthermore, the mRNA expression levels of MyHC I, PPARδ, MEF2C, NFATC1, and AMPKα1 were higher in CB than DLY pigs (p ˂ 0.05). Importantly, a total of 753 metabolites were detected in the two tissues (e.g., psoas major and longissimus dorsi) of CB and DLY pigs, of which the difference in metabolite profiles in psoas major between crossbreeds was greater than that in longissimus dorsi. Specifically, palmitic acid, stearic acid, L-aspartic acid, corticosterone, and tetrahydrocorticosterone were the most relevant metabolites of psoas major meat quality, and tetrahydrocorticosterone, L-Palmitoylcarnitine, arachidic acid, erucic acid, and 13Z,16Z-docosadienoic acid in longissimus dorsi meat were positively correlated with meat quality. The most significantly enriched KEGG pathways in psoas major and longissimus dorsi pork were galactose metabolism and purine metabolism, respectively. These results not only indicated improved meat quality in CB pigs as compared to DLY pigs but may also assist in rational target selection for nutritional intervention or genetic breeding in the swine industry.

The aim of the work were evaluation of selected morphological and carcass traits in broiler rabbits. The selected morphological traits were length of heads, cross size of heads, length of ears, cross size of breast, depth of breast, under-voltage, length of skillet, cross size of skillet, length of trunk, circumference of breast, semi-circumference. For analyse carcass traits was selected rabbits with morphological traits. The analyses carcass traits were weight of skin, weight of body, weight of head, weight of thigh, recovery and slaughter age. Traits of morphological and carcass were analysed using the Statistical Analysis System version 9.3.1. Between morphological traits was the high of variability in district of breast (6.18 %), district of breast (6.91%) and the lowest in length of ears (3.43 %), cross size of skillet (3.82 %). The high variability of carcass traits was in weight of skin (9.43 %), the lowest in weight of head (2.26 %) and recovery (2.5 %). The high of significant correlation was between weight of thigh and length of heads (0,188++), cross size of heads (0,227++). Obtained results will be exploitable for future rabbits breeding in the Slovak Republic.

The experiment was to investigate the effect of replacement of soybean by whole-plant fermented hybrid paper mulberry on growth performance, carcass traits and meat quality of finishing pigs. A total of 48 healthy three-way crossbred pigs weighing (60.53±2.42) kg were randomly divided into four groups, with three replicates in each group and four pigs in each replicate. The pigs in control group were fed with basic diet, group Ⅰ, group Ⅱ and group Ⅲ used 4%, 6% and 8% whole plant fermented hybrid paper mulberry instead of soybean meal, respectively. The pre-test period was 10 d, and the formal test period was 45 d. The results showed that compared with control group, the average daily gain and average daily feed intake of fattening pigs in group Ⅱ and group Ⅲ were significantly reduced (P<0.05). Compared with control group, the backfat thickness of finishing pigs in group Ⅱ and group Ⅲ was significantly reduced (P<0.05), and the eye muscle area of finishing pigs in each test group was significantly increased (P<0.05). Compared with control group, the water power of pork system in group Ⅱ and group Ⅲ was significantly decreased (P<0.05), and the drip loss was significantly increased (P<0.05), the cooking loss in group Ⅲwas significantly decreased (P<0.05), and shear force was significantly increased (P<0.05). The intramuscular fat content and protein content in each test group was significantly increased (P<0.05). The study indicates that 4% whole plant fermented hybrid paper mulberry substitute of soybean meal in diet can improve the carcass traits and meat quality of finishing pigs. [ABSTRACT FROM AUTHOR]

L-malic acid is a vital intermediate in the citric acid cycle and has been reported to improve the antioxidant capacity and aerobic oxidation of weaned piglets; however, its application in finishing pigs is limited at present. This study explored the effects of dietary L-malic acid supplementation on the carcass traits and meat quality of finishing pigs. In a 45-day experiment, 192 Duroc × Landrace × Yorkshire pigs (75.01 ± 0.51 kg) were divided into four treatments, i.e., a basal diet supplemented with 0, 0.5%, 1%, and 2% L-malic acid complex. The results showed that L-malic acid supplementation had no effects on the growth performance of finishing pigs. Importantly, L-malic acid significantly increased redness (a*) value at 24-h postmortem (quadratic, p < 0.05) and tended to increase the proportion of oxymyoglobin (OMb) (quadratic, p = 0.10), as well as the total antioxidant capacity (T-AOC) activity (quadratic, p = 0.08) in the longissimus dorsi (LD) muscle. Further, dietary supplementation of 1% L-malic acid markedly increased the protein expression level of slow skeletal myosin heavy chain (MyHC) in the LD muscle (p < 0.05). Moreover, 0.5% and 2% L-malic acid supplementation significantly increased carcass length and loin eye area (p < 0.05). In conclusion, dietary L-malic acid could effectively improve the meat color and carcass traits of finishing pigs. [ABSTRACT FROM AUTHOR]

High β-mannan content in the broiler diet could have adverse effects on performance and health. This study aimed to evaluate the possible effects of including a guar gum (GG) containing a high β-mannan content with the addition of β-mannanase in broiler diets on performance, pododermatitis and selected carcass traits. A total of 144 broilers were randomly allotted to three treatments from d 7-33. The control group (CON) received a pelleted diet without β-mannanase addition, whereas the second group (GG/-) was offered a diet with 1.30% of GG. The third group was fed a diet containing 1.30% GG (47.9% of β-mannan on a fresh basis) and with the recommended dose of β-mannanase (GG/+). Significant differences in body weight at d 33 were noted only between the CON and GG/- groups (2113 and 1854 g; p=0.0002). A significant difference of dry matter content in the litter-excrement mixture was observed at d 21 and 28 for the CON and GG/- groups (p=0.0349 and p=0.0348, respectively). Birds fed the GG/- diet had significantly the highest pododermatitis scores (1.04) compared to the GG/+ group (0.76) at d 33 (p=0.0355). Overall, supplementing the β-mannan-enriched diets with β-mannanase improved growth performance and contributed positively to reduce the severity of pododermatitis. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of different management systems (Intensive and semi-intensive systems) and using Zeolite substance as growth promoting on growth performance of Ossimi male lamb's, carcass traits, blood metabolites and economic efficiency. Twenty male lambs at 6 months of age were divided randomly to two groups (ten lambs per each group) were fed individually. Frist group lambs were reared on semi-intensive management system. The second group of lambs was reared on intensive management system. Every management system was divided into two feeding group (five lambs per each group), first group was fed on diet containing 0% Zeolite (control diet) according to NRC (2007) recommendations and the second group was fed on diet containing 1% Zeolite (treatment group). All experimental lambs in each group weighed fasting individually to the nearest kilogram monthly till the end of experimental period (120 days). Both of the consumed diets and refusals, if any, were recorded daily. Body weight gain, average daily gain, feed intake, feed conversion ratio and economic efficiency were then calculated. At the end of the fattening period six male lambs from each group were slaughtered for carcass evaluation. Furthermore, blood samples were collected and analyzed. Results showed that intensive management system lambs group fed on diet containing 1% Zeolite had a better growth performance, carcass traits, blood metabolites and economic efficiency of lambs and it had higher advantages without adverse effect on the studied traits. [ABSTRACT FROM AUTHOR]

The aims of this study was to investigate the influence of rabbits breed (Moshtohor and V-line), weaning age (28 and 35 days) and housing system (cages and floor type) on carcass traits and meat quality by using 120 male rabbits divided into two breed groups (60 Moshtohor rabbits and 60 V-line rabbits) each breed divided into two weaning groups (30 rabbits weaned at 28 days and 30 rabbits weaned at 35 days) each weaning group divided into two housing systems groups (15 rabbits raised in cages and 15 rabbits raised in floor). All experimental rabbits were fed concentrate feed mixture according to National Research Council, NRC (2004) recommendation based on the rabbits live body weight. Diets were offered twice daily in equal quantities at 8:00 and 16:00 and estimated for each group every day. Both of the consumed diets and refusals if any were recorded daily. All rabbits in each group individually weekly weighed from 5 to 13 weeks of age. Three rabbits from each group were randomly chosen at the end of the experimental period for slaughter test. Results showed that Moshtohor rabbits weaned at 35 days of age reared in cages had a higher carcass traits and meat quality than the other ones. Thus, we can concluded and recommended from this results that rabbits breeders can using Moshtohor rabbits, reared in cages and weaned at 35 days of age to earn the highest carcass traits and meat quality. [ABSTRACT FROM AUTHOR]

The demand for identifying substitutes for antioxidant feed additives in broiler production is increasing. The current study aimed to investigate the effects of Clostridium butyricum (C. butyricum) on carcass traits, antioxidant capacity, meat quality, and fatty acid composition of broiler chickens. A total of 330 one-day-old mixed-sex commercial Ross 308 broilers were randomly divided into five groups with six replicates per group and eleven broilers per replicate and reared for 39 days. The control (CON) group was fed a basal diet, the AM group was fed a basal diet containing 150 mg aureomycin/kg feed, and the CBL, CBM, and CBH groups were fed a basal diet containing 2 × 108, 4 × 108, and 8 × 108 colony-forming units (CFU) C. butyricum/kg feed. On day 21, compared to the AM group, serum total antioxidant capacity (T-AOC) level was enhanced in the CBH group and serum total superoxide dismutase (T-SOD) concentrations were increased in the CBM and CBH groups (p < 0.05). Dietary C. butyricum resulted in the liver T-AOC, T-SOD, and catalase (CAT) of broilers linearly increased at day 21 (p < 0.05). On day 39, supplementation with C. butyricum in broiler diets linearly increased concentrations of T-SOD (p < 0.05), CAT (p < 0.001), but linearly reduced MDA (malondialdehyde) contents (p < 0.001) in the liver. For the breast muscle, the redness for meat color increased in a linear manner and the shearing force decreased in a quadratic manner in response to C. butyricum inclusion (p < 0.05). The pH45min, pH24h, and the shearing force changed in a quadratic pattern (p < 0.05). The contents of total MUFA (monounsaturated fatty acid) and total PUFA (polyunsaturated fatty acid) were altered and quadratically responded to the doses of C. butyricum (p < 0.05). For the thigh muscle, the inclusion of C. butyricum in broiler diets showed the negative linear effects on the cooking loss and shearing force (p < 0.001). The total MUFA contents were changed linearly and quadratically (p < 0.001; p < 0.05), and the contents of total PUFA and the ratio of PUFA to SFA were quadratically responded to the doses of C. butyricum (p < 0.05). In brief, dietary C. butyricum could beneficially enhance liver antioxidant capacity, and improve meat quality and fatty acid composition in broilers. [ABSTRACT FROM AUTHOR]

For improving the performance of growing rabbits given salinity water and two levels of aqueous and ethanolic vitex extract, 75 New Zealand White growing rabbits of five weeks old and body weight of 553.00±0.091g were divided equally into 5 treatments. Control treatment was fed control diet. 5 and 7.5g/kg diet of the vitex leaves aqueous extract were supplemented to treatments two and three and 5.0 and 7.5g / kg diet of the vitex leaves ethanolic extract were supplemented to groups four and five for 15 weeks. Blood samples were collected at the end of the experiment for the clinical analysis. Body weight and feed intake were recorded weekly. Carcass characteristics and gut microbiome were determined. Rabbits given saline water and supplemented aqueous and alcoholic vitex extracts had higher (P<0.0001) final body weight. The ethanolic extract reduced (P<0.0001) feed intake and feed conversion. The control had the lowest digestibility coefficient of all nutrient’s digestion coefficients compared to treated groups. Carcass weight (P<0.022), carcass percent (P<0.017), and protein in the meat increased in all supplemented groups with no difference in the internal organs weight, dressing percent, and edible giblets. Vitex extracts (P≤ 0.05) increased total protein (P<0.003), triglycerides (P<0.001), and LDL (P<0.042) but declined ALT (P<0.028). Control group had the lowest cecum pH (P<0.011) and total volatile fatty acids ((P<0.017), high ammonia (P<0.009) and cecum microbial counts (P<0.001). Rabbits supplemented Vitex ethanolic extracts consumed the lowest feed intake and cost associated increased body weight gain with increasing the concentration. In conclusion, growing rabbits bred for meat production can be supplemented either the aqueous or the ethanolic extracts for longer intervals for improving their health, meat composition and reduce the costs. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the dietary effects of chromium methionine (Cr-Meth) chelate on growth performance, oxidative stress parameters, blood biochemistry, and carcass traits of broiler chickens. An experiment was conducted on 34,000 1-day-old straight-run broiler chicks (Indian River; 42.0 ± 0.03) at a commercial farm. The chicks were divided randomly into 3 groups; the first group contained 17,000 birds, which used as a control, whereas the second and third groups consisted of 7000 and 10,000 birds, respectively, with 5 replicates per group. A completely randomized design was used. The birds were fed the experimental diets containing graded levels of Cr-Meth chelate: 0 (control), 50, and 100 g/ton. This compound consisted of chromium (0.4%) chelated with methionine, and it supply the diets with 200 and 400 ppb Cr for the used levels of 50 and 100 g/ton feed, respectively. Growth performance indices (body weight, body weight gain, feed intake, and feed conversion ratio) were measured throughout the experiment. At the end of experiment, 10 birds per treatment were slaughtered, and the carcass yield with relative weight of the internal organs was determined. Also, blood samples were taken and analyzed for glutathione peroxidase activity, malondialdehyde, ALT, AST, total protein, albumin, glucose, urea, creatinine, triglycerides, and total cholesterol. It was found that Cr-Meth improved the body weight, weight gain, feed intake, and feed conversion ratio of broilers. Moreover, it reduced the mortality rate of birds. The chelated chromium can alleviate the oxidative status of birds by increasing the plasma glutathione peroxidase activity and reducing the serum malondialdehyde level. It was observed that the effects of 100 g/ton Cr-Meth chelate on performance indices, mortality rate, and oxidative stress parameters were better than that of 50 g/ton inclusion rate. Supplementation of Cr-Meth increased the total protein level, but reduced the glucose, total cholesterol, and triglyceride concentrations in the blood serum. In addition, it increased the carcass yield and reduced the abdominal fat percentage of the birds’ carcass. Therefore, chromium can be included in diets of broilers at a rate of 200 to 400 ppb, and the higher concentration was more effective than the lower one. So, it can be recommended to use Cr-Meth chelate in broiler diets at 100 g/ton to improve the productive performance and reduce the oxidative stress of birds. [ABSTRACT FROM AUTHOR]

Sheep are considered one of the main sources of animal protein in Egypt and the producers of sheep mutton eagers to find biological criteria for selecting fast-growing lambs that reach market weight early. Therefore, the present study aimed to find a link between the expression profile of selected candidate genes with growth performance and carcass traits of Barki lambs. Thirty-eight Barki lambs were kept and fed individually after weaning till 12 months of age and were divided into 3 groups according to growth performance (fast, intermediate, and slow-growing). Three samples were taken from different body tissues (eye muscle, liver, and fat tail) of each group, directly during slaughtering and stored at − 80 °C until RNA isolation. Real-time PCR was used to profile selected candidate genes (RPL7, CTP1, FABP4, ADIPOQ, and CAPN3) and GAPDH was used as a housekeeping gene. The results indicated that the final body weight was significantly (P ≤ 0.05) greater in the fast (49.9 kg) and intermediate (40.7 kg) compared to slow-growing animals (30.8 kg). The hot carcass weight was heavier (P ≤ 0.05) in the fast and intermediate-growing (24.57 and 19.07 kg) than slow-growing lambs (15.10 kg). The blood profiles of T3 and T4 hormones in addition to other parameters such as total protein, total lipids, and calcium level showed no clear variations among different experimental groups. At the molecular level, our data demonstrated upregulation of genes involved in protein biosynthesis (RPL7), fatty acid oxidation (CPT1), and lipolysis (FABP4) in the fast and intermediate-growing lambs in all studied tissues which facilitate protein accretion, energy expenditure, and fatty acid partitioning required for muscle building up. Moreover, the expression profile of the gene involved in muscle development (CAPN3) was increased in fast and intermediate-growing compared to slow-growing lambs in order to support muscle proper development. On the other hand, a candidate gene involved in lipogenesis (ADIPOQ) was expressed similarly in fat and liver tissues; however, its expression was increased in muscles of fast and intermediate-growing lambs compared to slow-growing animals. In conclusion, the current study indicated that the expression profile of genes involved in metabolic activities of liver, muscle, and adipose tissue is linked with the growth performance of lambs although no variations were detected in blood parameters. This provides an evidence for the importance of co-expression of these genes in body tissues to determine the final body weight and carcass characteristics of Barki sheep. [ABSTRACT FROM AUTHOR]

Simple Summary: The nutritional composition of the diets for growing rabbits should be well-balanced, both to meet the requirements of the high-producing hybrids currently used and to avoid nutrient losses. The improvement of the feed conversion ratio represents a key point in increasing rabbit farmers' profitability because of the high feeding costs. This study evaluated the growth performance, digestive efficiency and meat quality of growing rabbits belonging to the most diffused commercial crossbred rabbit breeds, Grimaud and Hyla, feeding them diets with different energy and protein levels. The two genotypes showed similar growth performance, but Grimaud rabbits achieved higher slaughter yield than Hyla rabbits. The administration of high-energy diets improved feed conversion and increased nutrient digestibility. Conversely, low dietary protein contents reduced nitrogen excretion without negative effects on growth, feed efficiency and carcass traits of fast-growing rabbits. The present study evaluated the effect of digestible energy (DE) and crude protein (CP) levels on growth, digestive efficiency, slaughter yield and meat quality in growing rabbits of two genotypes (Grimaud, G vs. Hyla, H). A total of 384 crossbred rabbits (192 G and 192 H), half males and half females, were divided into eight experimental groups according to a bi-factorial arrangement (2 genotypes × 4 diets; 48 animals/group) and reared in individual cages. From 33 to 64 days of age, rabbits were fed four diets obtained by combining two DE levels (high, HE—10.9 MJ/kg vs. low, LE—9.2 MJ/kg, on average) and two CP levels (high, HP—159 g/kg vs. low, LP—144 g/kg, on average). Then, all rabbits received the same fattening diet (10.7 MJ DE/kg; 156 g CP/kg) until slaughtering (77 days of age). Growth performance did not differ between genotypes for the entire trial (on average final live weight 3010 g; daily weight gain 50.5 g/d), but H rabbits showed a faster growth during the post-weaning period (p ≤ 0.01) compared to G rabbits, while exhibiting lower slaughter yield and lower carcass fatness (p ≤ 0.01). As DE level increased, feed intake decreased and feed conversion improved (p < 0.001), while caecal volatile fatty acid concentration increased and caecal pH and N-ammonia decreased (p ≤ 0.01). The reduction in the CP level did not affect performance and carcass traits. No significant interaction was detected between genotype and diet. In conclusion, G rabbits may have an advantage over H rabbits because of the higher slaughter yield. As for the nutritional characteristics of diets for high-producing crossbred rabbits, high energy levels are confirmed to enhance feed efficiency, whereas dietary CP can be reduced to 144 g/kg without negative effects on performance and carcass traits. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural, Environmental & Veterinary Sciences is the property of Arab Journal of Sciences & Research Publishing (AJSRP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Crossbreeding has the advantage of benefiting from the effect of heterosis. A current crossbreeding experiment was conducted using Black Bronze (BB) and Large White Converter (CC) turkeys. Artificial insemination of 40 mature hens of CC with 6 toms of BB, and 40 mature hens of BB with 6 toms of CC were used to obtain F1 of the two turkey crosses (CB and BC) respectively. A total of 160 poults of the four groups of turkeys were taken in the evaluation in this study. This evaluation included some growth and carcass traits, and some biochemical blood and oxidative profile parameters. It was noticed that the body weight at different ages was higher in the large white turkeys-Converter, CC group, and then the crossbreed BC (BB toms × CC hens) group. The means of daily weight gain (DWG) and feed intake (FI) at different periods of age were highly significant (P≤0.05) high in CC followed by BC and CB turkeys. Feed conversion (FC) reached the lowest values in CC while the BB genotype was having the highest values. The crosses showed significant values in percentages of carcass/live body weight compared to BB. The hind part of the carcass differed significantly (P≤0.05) among the four groups of birds regardless of other parts (neck, wing, and chest/carcass). Blood serum protein, glucose, urea, and albumin levels were not significantly affected by the genotype. However, globulin and triglyceride levels were affected significantly (P≤0.05) by the genotype. Oxidative profile parameters were affected significantly (P≤0.05) by the genotype. The crossbreeding parameters obtained showed that the additive effect was significant for DWG and FI during the periods from hatching to 24 weeks while it was not significant for FC. The additive effects were not significant for carcass traits, and biochemical blood profile parameters except for glutathione reductase and total antioxidant capacity. The cross effect was significant for DWG during the periods hatching-12, only. The cross effect in FI during the period from hatching to 24 weeks was significant while it was not significant in FC. The cross effects of the two reciprocal crosses were not significant in all carcass parameters and biochemical blood profiles. The oxidative profile was not significantly different in the cross effect except for hydrogen peroxide (HP) and; malondialdehyde. Presumably, the crossbreeding between large white Converter turkeys with Bronze turkeys was to benefit from the effect of heterosis. The crosses have a growth performance and carcass traits higher with a relative growth advantage when the hens were Hybrid Converters. The first generation in crossbreeding could be submitted to selection for the constitution of a synthetic strain. [ABSTRACT FROM AUTHOR]

Simple Summary: Essential oils can be used to improve animal performance as well as the health and quality of livestock products. The aim of this study was to evaluate the effects of essential oil supplementation on animal performance, ruminal fermentation, blood metabolites, and meat and milk quality of small ruminants through a meta-analysis. Supplementation with essential oils improved weight gain, milk production and composition, oxidative stability of meat, and blood serum antioxidant enzyme activity. Additionally, essential oils decreased methane emissions. This suggests that the inclusion of essential oils in the diets of small ruminants could be used to improve animal performance and the quality of meat and milk, in addition to reducing the environmental impact and oxidative stress of the animals. There is an increasing pressure to identify natural feed additives that improve the productivity and health of livestock, without affecting the quality of derived products. The objective of this study was to evaluate the effects of dietary supplementation with essential oils (EOs) on productive performance, rumen parameters, serum metabolites, and quality of products (meat and milk) derived from small ruminants by means of a meta-analysis. Seventy-four peer-reviewed publications were included in the data set. Weighted mean differences (WMD) between the EOs treatments and the control treatment were used to assess the magnitude of effect. Dietary inclusion of EOs increased (p < 0.05) dry matter intake (WMD = 0.021 kg/d), dry matter digestibility (WMD = 14.11 g/kg of DM), daily weight gain (WMD = 0.008 kg/d), and feed conversion ratio (WMD = −0.111). The inclusion of EOs in small ruminants' diets decreased (p < 0.05) ruminal ammonia nitrogen concentration (WMD = −0.310 mg/dL), total protozoa (WMD = −1.426 × 105/mL), methanogens (WMD = −0.60 × 107/mL), and enteric methane emissions (WMD = −3.93 L/d) and increased ruminal propionate concentration (WMD = 0.726 mol/100 mol, p < 0.001). The serum urea concentration was lower (WMD = −0.688 mg/dL; p = 0.009), but serum catalase (WMD = 0.204 ng/mL), superoxide dismutase (WMD = 0.037 ng/mL), and total antioxidant capacity (WMD = 0.749 U/mL) were higher (p < 0.05) in response to EOs supplementation. In meat, EOs supplementation decreased (p < 0.05) the cooking loss (WMD = −0.617 g/100 g), malondialdehyde content (WMD = −0.029 mg/kg of meat), yellowness (WMD = −0.316), and total viable bacterial count (WMD = −0.780 CFU/g of meat). There was higher (p < 0.05) milk production (WMD = 0.113 kg/d), feed efficiency (WMD = 0.039 kg/kg), protein (WMD = 0.059 g/100 g), and lactose content in the milk (WMD = 0.100 g/100 g), as well as lower somatic cell counts in milk (WMD = −0.910 × 103 cells/mL) in response to EOs supplementation. In conclusion, dietary supplementation with EOs improves productive performance as well as meat and milk quality of small ruminants. In addition, EOs improve antioxidant status in blood serum and rumen fermentation and decrease environmental impact. [ABSTRACT FROM AUTHOR]

The food security of a country can be harmed if the supply and demand of poultry products are affected due to any disruptions disrupted by factors such as poor growth rates and disease outbreaks. On top of that, with regard to food safety reasons, developed countries have started to prohibit the inclusion of antibiotics in livestock feed. As a result, it is essential to seek alternative preventive substitutes for growth promotion and prophylaxis in poultry rather than depending on antibiotics. Plant extracts are one of the alternatives with anti-microbial and growth-promoting effects on poultry. Saponins have many biological and pharmacological activities like anti-carcinogenic, anti-microbial, anti-parasitic, anti-fungal, anti-inflammatory, hypocholesterolemic, immunomodulatory, and anti-oxidant properties. Because of its growth-promoting effect, immunity enhancer, and microbial capabilities, saponins from diverse sources and quantities could be used as an anti-microbial alternative to synthetic antibiotics in the broiler industry. Additionally, steroidal saponins have been commercialized as supplements for poultry, health foods for human consumption, and potential anti-cancer treatments. Therefore, the present review will critically shed light on the availability of different saponins and the influence on the production performance and immunopathology responses of poultry supplemented with different saponins extract. Information from this review will added knowledge on the usability of different saponins extracts which could be considered as a novel feed additive in the poultry industry. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was conducted to determine the effect of zinc on the productive performances, carcass yield and blood profiles of broilers. Experiment was done for a period of 35 days with a number of 60, day old broiler chicks. Birds were divided into four dietary treatment groups with 3 replications each having 5 birds per replication. The dietary treatment groups were; T0 (basal diet; no zinc), T1 (basal diet + 50 mg zinc/kg feed), T2 (basal diet + 100 mg zinc/kg feed), T3 (basal diet + 150 mg zinc/kg feed). Results revealed that body weight and body weight gain were significantly increased in the zinc supplemented group compared to the control group. Higher feed intake and better FE were also observed in the zinc supplemented group than the control group and the best performance was observed in the group fed 150mg zinc/kg feed (T3). Carcass yield was significantly higher in the groups fed dietary zinc. Net profit was slightly higher in the T3 group but not significantly (P.0.05) differed with the control group. However, T1 and T2 showed less profit even than the control group. Blood profile of the experimental birds including Hb, PCV, and ESR did not significantly differ among the groups. The results indicate that the addition of zinc in the broiler diet improves productive performances, carcass yield and increases net profit without affecting the health status of broiler. So, zinc can be used as an effective and useful micronutrient to improve the performances of broiler.