Search Results (970)

This study evaluated the performance, carcass yield, and meat quality of slow-growing chickens fed diets containing different levels of replacement of crude protein from soybean meal with crude protein from cottonseed meal (CSM), with and without supplementation of 2% lysine. A total of 600 male chickens of the Red Colonial heavy strain were used and evaluated from 8 to 56 and to 77 days of age. In Experiment 1, chickens were fed diets with 0, 15, 30, and 45% replacement of soybean meal protein by CSM protein; in Experiment 2, the same replacement levels were associated with supplementation of 2% lysine based on the protein content of CSM. The 15% replacement level promoted higher live weight and average weight gain at 56 and 77 days. Feed conversion ratio at 56 and 77 days indicated that replacing soybean meal protein with CSM protein, with the addition of 2% lysine relative to the protein value, resulted in improved values for this variable. It is concluded that replacing up to 15% of soybean meal protein with cottonseed meal protein, with or without supplementation of 2% lysine, does not compromise productive parameters, carcass yield, or meat quality in slow-growing chickens. Full article

This study evaluated the effects of including palm kernel oil in the diets of pasture-raised sheep on carcass characteristics, meat quality, and fatty acid profiles. A completely randomized design with four treatments was used, consisting of 0, 20, 40, and 60 g/kg of palm kernel oil in the dry matter of the supplement, with eight replicates. Thirty-two uncastrated Santa Inês sheep, with an average initial body weight of 23.2 ± 2.6 kg, were used in this study. The animals were kept on Aruana grass (Panicum maximum (syn. Megathyrsus maximum) cv. Aruana) pastures under continuous stocking for 59 days (preceded by 15 days of adaptation), with each one fed supplements (1.4% of body weight) at 8 am. At the end of the experimental period, the animals were slaughtered in a commercial slaughterhouse for carcass and meat quality evaluation. The inclusion of palm kernel oil had a decreasing linear effect on hot and cold carcass weight (p = 0.0403) (p = 0.0398), but it did not affect hot or cold carcass yields or carcass morphometric measurements, commercial cut weights, pH, or loin area (p > 0.05). However, it affected the color of the L. lumborum muscle, showing an increasing linear effect on yellow intensity (b*) (p = 0.002) and on the centesimal composition, with an increasing linear effect on ether extract content (p = 0.006). Shear force, cooking loss, and water-holding capacity were not affected (p > 0.05). Fatty acid profiles, the atherogenicity and thrombogenicity indices, and the ratio of hypocholesterolemic to hypercholesterolemic fatty acids (h:H) were also unaffected by the inclusion of palm kernel oil (p > 0.05). The inclusion of up to 60 g/kg of palm kernel oil in the diets of pasture-raised sheep had an effect on carcass weight but not yield. It also had an effect on the color and chemical composition of L. lumborum muscle, but these changes did not compromise the overall quality of the meat. Full article

This study evaluated the effects of sex and genetics on carcass traits and pork quality in 180 carcasses from castrated males and females of three commercial lines: A (Pietrain × Duroc × Large White × Landrace), B (Line A × Pietrain) and C (Line A × Hampshire). Males showed greater backfat (14.05 vs. 13.38%) and lower lean meat (58.65 vs. 59.08%) than females. Line C exhibited the highest marbling score (2.82) and hot and cold carcass weights (90.04 and 88.05 kg), while Line B achieved the highest ham yield (32.5%). Castrated males had higher marbling (2.74 vs. 2.48) but lower shear force (3.68 vs. 3.90 kgf) than females. Line C showed the highest marbling (2.82) and shear force (4.04 kgf). Males of Line C had longer sarcomeres than females of the same line and males from Line B. Males exhibited higher protein (24.73 vs. 23.91%) but lower mineral content (1.55 vs. 1.85%) than females. Line A had the highest mineral content (1.90%). Collagen content was highest in males from Lines A and B (insoluble: 0.35–0.38%; soluble: 0.09%; total: 0.44–0.47%), and lower in Line C (insoluble: 0.18%; soluble: 0.04%; total: 0.21%). These results indicate that sex and new genetic lines influence carcass composition and instrumental meat quality traits. Full article

Yanhuang cattle is a specialized beef breed independently developed in China with high economic value. However, the effects of the horned/polled trait on its production performance and the underlying genetic markers are poorly understood. This study aimed to evaluate the impact of horn status and to validate candidate genetic markers for the polled trait in this breed. A total of 60 Yanhuang cattle (30 horned and 30 polled) were used for comparative analysis of growth, carcass, and meat quality traits. Additionally, blood samples from 200 individuals (100 horned and 100 polled) were collected for molecular screening of seven candidate genetic markers previously associated with polledness in cattle. The polled cattle showed significantly higher body weight from 12 months onward. Body height and hip height were significantly greater at 12, 18, and 24 months, while body length displayed significant advantages at 6, 18, 24, and 30 months. Polled cattle also outperformed in chest girth (18 months), abdominal circumference (significant at 18–30 months), and ischial end width (significant at 6–12 months). Regarding slaughter traits, polled cattle exhibited higher carcass weight, along with significantly improved slaughter and net meat rates, though no differences were observed in meat quality. At the molecular level, the P_202ID indel marker was successfully validated in the polled Yanhuang population. Our findings demonstrate that the polled trait is associated with superior production performance in Yanhuang cattle, and the P_202ID marker represents a reliable molecular tool for polled selection, providing a theoretical and technical basis for the genetic improvement and breeding of this breed. Full article

This study evaluated the effects of dietary spirulina (Spirulina platensis) supplementation on the physiological status and bone quality of juvenile ring-necked pheasants. A total of 200 one-day-old chicks were randomly allocated to a control group fed a basal diet or to an experimental group fed a basal diet supplemented with 15 g of spirulina/kg feed and reared under identical conditions for 42 days. Growth performance, feed intake, the feed conversion ratio, selected carcass traits, meat and bone quality, and biochemical and hematological parameters were assessed. Pheasants receiving spirulina presented significantly greater body weights at four weeks of age. The experimental group also exhibited increased pH values in pectoral and thigh muscles and increased postmortem muscle temperature. Spirulina supplementation significantly improved tibia quality, as reflected by enhanced geometric, structural, and material bone properties. The birds fed spirulina presented increased plasma total cholesterol and low-density lipoprotein concentrations, whereas those in the control group exhibited increased malondialdehyde levels, indicating increased oxidative stress. In addition, spirulina increased the proportion of lymphocytes and reduced both the proportion and absolute number of monocytes. In conclusion, spirulina supplementation increased tibia bone strength, reduced oxidative stress, and had immunomodulatory effects on juvenile pheasants. Full article

This study evaluated the effects of forage-free diets with reduced starch levels on the productive performance, metabolism, ruminal fermentation, nutrient digestibility, and meat quality of feedlot beef cattle. Two experiments were conducted. In Experiment 1, forty uncastrated Nellore steers were distributed into 20 pens in a completely randomized design, receiving diets with increasing inclusion levels of ground corn in the total diet: C400 (400 g kg⁻¹), C200 (200 g kg⁻¹), C100 (100 g kg⁻¹), and C50 (50 g kg⁻¹), formulated without forage and based on fibrous co-products. Increasing ground corn inclusion promoted linear improvements in final body weight and average daily gain, while dry matter intake and feed efficiency showed quadratic responses. Meat quality parameters were not affected by dietary treatments. In Experiment 2, eight crossbred steers were assigned to a double 4 × 4 Latin square design and fed the same experimental diets. Higher corn inclusion increased starch and fat intake, whereas dry matter, organic matter, and protein intake showed quadratic responses. Apparent total-tract digestibility of dry matter, organic matter, and starch also followed a quadratic pattern. Ruminal fermentation parameters were affected by dietary treatments, with greater ammoniacal nitrogen concentrations at higher corn levels and quadratic responses for propionate, butyrate, and methane production. Nitrogen metabolism indicated increased urinary nitrogen and uric acid excretion with increasing dietary corn inclusion. These results demonstrate that forage-free diets based on citrus pulp and soybean hulls with different levels of ground corn can be effectively used in finishing beef cattle, improving performance without impairing meat quality while modulating ruminal fermentation and nutrient utilization. Full article

Reducing input costs, especially feed ingredients, remains a priority for production agriculture. Identifying and selecting nutritionally dense ingredients is vital to maximize animal performance. Objectives of the current study were to evaluate the impact of biochar supplementation on goat carcass characteristics and fresh meat quality. Goats (N = 36) were allocated to a diet concentration formulated with or without (Control, Low, Medium, or High g/kg) biochar. After 60 days of feeding, goats were harvested, and carcass measurements were collected. Subprimals from the leg were fabricated into steaks for laboratory analysis of surface color, cook loss, and instrumental tenderness. Biochar supplementation did not alter organ weights (p = 0.0614), dressing percentage (p = 0.8139), loin eye area (p = 0.9570), or tenderness (p = 0.0144). However, marbling scores were lower in goats fed at the medium biochar supplementation rate (p = 0.0114) and high supplementation (p = 0.0102) compared to the control. An interaction between storage day and biochar supplementation was recorded for instrumental surface color lightness (L*; p = 0.0016), redness (a*; p = 0.0547), hue angle (p = 0.0313), and red-to-brown (p = 0.0591). Steaks from the 0.052% supplementation group exhibited greater (p = 0.0003) redness (a*) during a 7-day refrigerated display and increased chroma values (p < 0.0001). Storage duration influenced all color traits, with steak surface discoloration increasing as storage time increased (p < 0.0001). Results conclude that biochar supplementation does not negatively impact all carcass quality or tenderness traits, but may influence fat deposition and improve meat color stability. Full article

Both breed and plumage color are considered potential genetic factors influencing meat quality in pigeons, yet their independent effects remain poorly distinguished. This study aimed to disentangle the regulatory roles of breed and plumage color on meat quality, nutritional composition, and flavor-related metabolites in meat pigeons. White-feathered (SQB) and grey-feathered (SQH) Shiqi pigeons were compared with European Mimas white pigeons (MMS) under identical rearing conditions. Slaughter performance, meat quality traits, and flavor profiles were assessed, followed by untargeted metabolomics and transcriptomics sequencing of pectoral muscle tissues. The results demonstrated that breed exerted a significant influence on carcass traits, water-holding capacity, collagen content, as well as the composition of fatty acids and free amino acids. In contrast, no notable disparity in meat quality was observed between the white- and gray-feathered varieties within the same Shiqi pigeon breed. A total of 114 and 205 differentially expressed metabolites (DEMs), and 11 and 327 differentially expressed genes (DEGs) were identified in plumage color and breed comparisons, respectively. Key flavor-associated metabolites, including glutathione, L-histidine, L-carnosine, and cytidine-5′-monophosphate, were identified as candidate biomarkers for breed-specific flavor differentiation. Breed is the dominant genetic factor determining meat quality and flavor in meat pigeons, while plumage color variation within breed has a limited impact. The identified pathways and regulatory networks provide actionable targets for the precision breeding and flavor enhancement of local pigeon breeds. Full article

Background/Objectives: Genome-wide association studies (GWAS) based on single-step genomic BLUP (ssGBLUP) commonly assume equal single nucleotide polymorphism (SNP) variances, which may not reflect the biological architecture of complex traits. Alternative weighting strategies can increase detection power but may affect stability. This study evaluated how different SNP weighting approaches influence genomic region detection and biological interpretation of ribeye area (REA) and subcutaneous fat thickness (SFT) in Guzerá cattle. Methods: Phenotypic records from 2729 animals and genotypes from 1405 individuals (43,039 SNPs after quality control) were analyzed. Heritabilities were estimated using Restricted Maximum Likelihood (REML), and GWAS were conducted under five approaches: unweighted method (UM), quadratic method (QM), and three Non-Linear A strategies with weighting constants (1.125, 1.2, and 1.5). Genomic windows of 20 adjacent SNPs explaining ≥0.5% of the additive genetic variance (AGV) were considered significant. Recurrent regions were prioritized, and functional enrichment analyses (KEGG, GO, and MeSH) were performed. Results: Heritability estimates were moderate for REA (0.26 ± 0.05) and SFT (0.22 ± 0.04). Weighted approaches increased detection sensitivity. For REA, UM identified 10 windows, whereas QM and A_1.5 detected 24 and 31 windows. For SFT, UM identified 8 windows, while QM and A_1.5 detected 30 and 23 windows. Recurrent chromosomes included 2, 4, 6, 12, 16, 19, and 22 for REA, and 2, 3, 5, 7, 11, 17, and 22 for SFT. Key genes included AKT3, NOS2, and MSTN. Enrichment highlighted pathways related to muscle growth and lipid metabolism. Conclusions: SNP-weighted GWAS increased detection sensitivity but involved trade-offs between signal amplification and stability. Integrating weighting strategies improves biological interpretation and supports robust candidate gene identification for genomic selection. Full article

Although soybean meal (SBM) is generally used as the main protein source in livestock diets, canola meal (CM) appears as a sustainable alternative, since it lowers diet cost, especially when regionally produced, while still meeting animal nutritional needs. The objective of this study was therefore to assess the effects of dietary protein source (SBM vs. CM) on carcass traits and meat quality characteristics of feedlot-fattened dairy lambs. A total of 193 weaned lambs, approximately 3 months of age, from two indigenous Greek dairy breeds (75 Chios and 118 Serres), were used. Lambs were randomly assigned to one of two isocaloric and isonitrogenous dietary treatments: a control ration containing SBM as the primary protein source, and an alternative ration in which SBM was completely replaced by CM. After a fattening period of 13 weeks for Chios lambs and 15 weeks for Serres lambs, animals were slaughtered upon reaching a live weight of 35–40 kg, and hot and cold carcass weights were recorded. After 24 h of carcass storage at 4 °C, Longissimus lumborum muscle was sampled and used for the measurement of pH, colour attributes, cooking loss, shear force, and intramuscular fat content. Lipid oxidation was evaluated on days 1, 3, 6, and 9 of refrigerated storage at 4 °C. The substitution of SBM by CM as the main dietary protein source did not affect carcass traits in Serres lambs, whereas CM- treated Chios lambs showed an increased hot and cold carcass weight (p < 0.05). Meat quality characteristics were not affected by the dietary treatment in either Chios or Serres lambs, with the exception of meat oxidative stability that was deteriorated in CM compared to SBM Serres lambs (p < 0.001). In conclusion, the utilization of canola instead of soybean meal did not negatively influence carcass traits or meat quality characteristics in either Chios or Serres lambs, with the exception of lipid oxidation which was significantly higher in CM supplemented Serres lambs. Full article

This study evaluated the effects of a host-specific multi-lactic acid bacterial (MLAB) probiotic and sex on performance, carcass traits, meat quality, and gut microbiota in fattening pigs. Thirty-two crossbred pigs (10 ± 0.80 weeks; 23.43 ± 0.17 kg) were assigned to a 2 × 2 factorial design with diet (control or MLAB probiotics) and sex (barrow or female). The MLAB supplement consisted of seven lactic acid bacterial strains mixed in equal proportions (≈14.3% each)—Lactobacillus brevis, Lactobacillus reuteri, Weissella cibaria, Lactobacillus paraplantarum, Lactococcus lactis, Lactobacillus pentosus, and Pediococcus pentosaceus—administered at 1 × 10⁹ CFU/kg feed for 12 weeks. MLAB probiotic supplementation reduced bone proportion while increasing skin and fat content (p < 0.05), with a treatment × sex interaction for loin eye area (p < 0.05). Meat quality improved in the MLAB group, showing higher ultimate pH and lower cooking loss (p < 0.05), indicating improved water-holding capacity. Female pigs exhibited higher early postmortem pH and protein content (p < 0.05). Microbiome analysis revealed increased abundances of Oxalobacteraceae and Paludibacteraceae and reduced Clostridium sensu stricto 6 (p < 0.05). These results suggest that host-adapted probiotics may support gut microbial balance and improve certain pork quality traits. Full article

This study evaluated the effects of different environmental enrichment tools on broiler chickens from 1 to 21 days of age. A total of 120,000 one-day-old broiler chicks were randomly assigned to five treatments, each consisting of four replicates with 6000 birds per replicate. Replicates were housed in pens measuring approximately 362 m². The treatments included: T1, green balls (approximately 40 balls per pen); T2, hanging toys (8–10 toys per pen); T3, hanging strings (8–10 string bundles per pen); T4, rotational use of green balls, hanging toys, and strings at equivalent densities; and T5, a control group without enrichment. Data were collected on growth performance, foot health, behavioral activity, serum biochemical parameters, and carcass and meat quality traits. Birds provided with hanging enrichment tools showed significantly improved growth performance (p ≤ 0.05) compared with the control group. Among enriched treatments, T2 yielded the highest body weight and weight gain, as well as the lowest feed conversion ratio. Enrichment treatments also resulted in significant improvements (p ≤ 0.05) in carcass characteristics and selected meat quality parameters, including lightness (L*) and pH stability. Behavioral observations indicated substantially higher activity levels in enriched groups relative to the control. Toe damage scores differed significantly among treatments (p = 0.004), with the lowest scores observed in T1 and the highest in T4; however, no significant differences were detected in footpad dermatitis or hock burn scores (p > 0.05). In conclusion, hanging environmental enrichment tools, particularly hanging toys, can effectively enhance growth performance, behavioral activity, and selected carcass and meat quality traits in broiler production systems, while their effects on footpad health appear limited under the conditions of this study. Full article

The objective of this study was to evaluate the effects of zilpaterol hydrochloride supplementation strategies on growth performance, dietary energetics, carcass traits, and meat quality in feedlot finishing lambs. Twenty-four Dorper × Katahdin crossbred male lambs (45.5 ± 4.53 kg, mean ± SD) were used in a 27 d feeding trial. The zilpaterol supplementation strategies were: (1) control, no zilpaterol supplementation (CON); (2) zilpaterol administered once daily as a full dose in the morning feeding (ZMOR); (3) zilpaterol incorporated into the total mixed ration and continuously available throughout the day (ZMIX); and (4) intermittent zilpaterol supplementation applied in a daily alternating pattern, one day on, one day off (ZINT). A target dose of 0.20 mg/kg live weight of zilpaterol hydrochloride per administration was used for all supplemented treatments, with daily administration in ZMOR and ZMIX and alternate-day administration in ZINT. Compared to the CON, zilpaterol supplementation through the ZMOR + ZMIX strategies improved average daily gain (ADG) and feed efficiency (FE) by 28.6% and 18.5%, respectively. Additionally, dressing percentage and longissimus thoracis muscle area increased by 3.2% and 17.0%, respectively. The ZINT strategy also enhanced ADG by 20.9% and FE by 15.4%. However, ZINT did not improve hot carcass weight or dressing percentage. All zilpaterol supplementation strategies increased meat toughness by up to 39.2%. Results indicate that both the ZMOR and ZMIX strategies optimize the response to zilpaterol, with no evidence that ZMOR supplementation results in a diminished response. Full article

Probiotics have emerged as an important strategy to achieve improved feed efficiency and carcass quality. To evaluate the effects of a probiotic combination based on Weizmannia faecalis (formerly Bacillus coagulans) and Bacillus licheniformis on broiler performance, carcass, and intestinal health, a study was conducted. As-hatched ROSS 308 broilers were purchased from a local hatchery at day 0 and were randomly allocated to two treatments (160 birds per treatment; 8 replicates of 20 birds each): the control, which was fed a standard commercial diet throughout the experiment, and the probiotics group, where the standard diet was further supplemented with the probiotic combination. Feed and water were offered for ad libitum consumption while the feeding schedule was as follows: Starter, 1–10 days, mash; Grower, 11–24 days, mash; Finisher, 25–42, mash. The birds were challenged using re-used litter as bedding and the application of increased stocking density and mild heat stress. The final body weight of the probiotics’ supplemented group was higher than the control at 42 days of age (2822.7 g vs. 2575.4 g, respectively) (p < 0.05), and the overall feed conversion ratio was significantly reduced. The weight of all the commercial parts increased, along with the thigh and drumstick yield, thus indicating an improvement of carcass composition (p < 0.05). The European Poultry Efficiency Factor significantly improved following the probiotic dietary supplementation (409.7 vs. 344.9 of the control), while the probiotic fed birds had higher antibody titers for Bursal disease at 42 days and lower serum concentration of fatty acid binding protein 2 at 24 days (p < 0.05). Overall, the dietary supplementation of broilers with the probiotic mixture, under challenging rearing conditions, enhanced growth performance and improved carcass composition. Full article

This study evaluated the growth performance, carcass characteristics, and meat quality of male Alpine and Saanen goat kids raised under standardized fattening conditions to inform breed-specific strategies for meat production. The study included 36 single-born male kids (18 Alpine and 18 Saanen purebreds) of similar age and live weight. The animals were allocated by breed and randomly assigned to three replicates per breed, with six animals in each replicate. After a two-week adaptation period, the kids were fattened for 12 weeks on an 80:20 concentrate–roughage diet. At the end of the fattening period, all animals were slaughtered, and physical, sensory, and chemical analyses of the meat were performed on the Longissimus lumborum (LL) muscle. Final live weights did not differ significantly between Alpine and Saanen kids, nor did average daily gains. However, the feed conversion ratio favored the Saanen breed, indicating superior feed efficiency. Alpine kids had significantly higher internal fat content, while Saanen kids had a higher proportion of full intestines. Meat pH, color, and texture were similar between breeds. Fatty acid analysis showed that Alpine meat had higher palmitic and palmitoleic acid content, whereas Saanen meat contained more calcium and sodium. These results suggest that both breeds are suitable for high-quality meat production under controlled feeding conditions, but breed-specific differences in fat composition and mineral content may affect nutritional value and market positioning. These findings are valuable for optimizing selection and marketing strategies in goat meat production systems targeting diverse consumer demands. Full article