Chanporn Chaosap

The transition from antibiotic-based (AB) to antibiotic-free (ABF) broiler production represents a major shift in poultry management, with potential implications for flock health, welfare, and processing outcomes. This study evaluated its impact on condemnation percentage (%condemnation) using Bayesian structural time-series (BSTS) analysis. Data from a Thai integrator comprised 105,899 truckload-level records (2015–2020) across 260 contract farms. The AB period (2015–2017) served as the baseline, and the ABF period (2018–2020) was assessed using counterfactual projections. Time-series decomposition and change-point analysis revealed an increasing trend in %condemnation during the early phase of ABF implementation, followed by a decline in 2020, with five structural shifts detected. The BSTS model estimated an absolute effect of +1.10% (95% CI: −1.50 to 3.80; p = 0.207) and a relative effect of +95% (95% CI: −38% to 657%), indicating no statistically significant causal impact. The transient increase may reflect short-term adaptation challenges, whereas subsequent stabilization may be associated with adaptation to ABF production and other concurrent management changes. Overall, the transition from AB to ABF production did not significantly affect %condemnation. Adaptive management measures were implemented as a company-wide policy but were not directly evaluated within the BSTS framework.

Objective: This meta-analysis evaluated the effects of dietary crude glycerol (CG) supplementation on growth performance, carcass traits, meat quality, and blood biochemical parameters in broiler chickens.Methods: A systematic search of peer-reviewed studies in Scopus, ScienceDirect, and Google Scholar was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Twenty-five eligible studies were included. Effect sizes were calculated as standardized mean differences using a random-effects model in Open-MEE software. Subgroup analyses were performed according to strain, sex, rearing phase, and inclusion level.Results: CG supplementation increased body weight gain (p<0.05) and improved feed conversion ratio (p<0.05), while feed intake was unaffected. Among carcass traits, breast yield increased (p<0.05), whereas carcass yield and thigh yield were not affected. CG inclusion also reduced meat ash content and ultimate pH, while drip loss increased, indicating potential negative effects on water-holding capacity. Blood biochemical indices, including reduced alanine aminotransferase and elevated alkaline phosphatase, indicated adaptive physiological responses without evidence of toxicity. Subgroup analyses revealed that strain, sex, and inclusion level moderated growth outcomes (p<0.05).Conclusion: CG can be incorporated into broiler diets as an alternative energy source to enhance growth performance without compromising carcass yield. However, its influence on meat quality highlights the need to optimize inclusion levels and consider variability among glycerol by-products before large-scale application.

This study evaluated the effects of dietary crude glycerol supplementation on laying performance, egg quality traits, and egg yolk fatty acid composition in laying hens. A systematic search of peer-reviewed literature from major scientific databases identified thirteen eligible studies. Effect sizes were calculated as mean differences using random-effects models, and subgroup and meta-regression analyses were conducted to assess the influence of inclusion level, hen age, strain, and dose–response relationships. Moderate inclusion of crude glycerol (≤4%) significantly increased egg production (MD = +0.71 percentage points; p = 0.019) and egg mass (MD = +1.08 g; p = 0.007). External egg quality traits, including shell thickness, shell breaking strength, and shell percentage, were not significantly affected, while albumen height decreased slightly (MD = −0.14 mm; p = 0.004) and Haugh unit remained unchanged. Crude glycerol supplementation also increased linoleic acid, total unsaturated fatty acids, and total polyunsaturated fatty acids (p < 0.001). Responses varied with inclusion level, hen age, and strain, and a positive dose–response relationship between crude glycerol level and yolk linoleic acid was observed in white-egg strains. Overall, moderate crude glycerol inclusion can partially replace conventional dietary energy sources with minimal adverse effects on egg quality.

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.

This study evaluated the productivity and egg quality of Japanese quails reared under different LED colors and rearing systems. A total of 720 female quails were assigned to a 3 × 2 factorial arrangement with three LED colors (red, green, and white) and two rearing systems (cage and floor) until 20 weeks of age. Production performance was evaluated across specific age intervals, while physical egg quality traits were analyzed using a Repeated-measures General Linear Model to assess temporal changes. No significant overall interactions between LED color and rearing system were observed (p > 0.05). However, significant interactions between treatment and time (p < 0.05) revealed that red LED light progressively enhanced productivity, while the floor system significantly improved feed efficiency and income during the early laying phase (weeks 6–12). Specifically, red LED light significantly improved hen-day production, egg mass, feed efficiency, and income-to-cost ratio compared to other colors (p < 0.05). Physical egg quality traits remained consistent across treatments (p > 0.05) but were significantly influenced by time (p < 0.05). In conclusion, red LED light optimizes long-term profitability, whereas the floor system offers distinct advantages during the onset of lay.

The influence of dietary hemp ( Cannabis sativa L.) leaf (HL) supplementation in a concentrate diet on carcass traits, physicochemical properties, amino acids, ribonucleotides, lipid oxidation, and fatty acids of Longissimus thoracis et lumborum (LTL) muscle in goat kids was evaluated. Fifteen entire Thai native x Boer bucks (body weight: 16.28 ± 0.35 kg; age: 4 months) were randomly assigned to concentrate diets containing 0% (HL-0), 2% (HL-2), or 4% (HL-4) HL for 150 days, after which they were slaughtered. The LTL muscles were assessed for physicochemical properties, fatty acids, amino acids, ribonucleotides and lipid oxidation. The HL-4 goats had heavier hot and cold carcass weights compared to the other groups ( P < 0.05). Shoulder percentage was lower in the HL-0 goats than in the other groups ( P < 0.05). The diets did not affect color, chemical composition, shear force, muscle fiber diameter, sarcomere length, ribonucleotides, or free and total amino acids in the LTL muscle in goats. However, the HL-4 meat had higher ( P < 0.05) pH 24 h compared to the HL-2 meat, while the pH of the HL-0 meat did not differ from that of the other groups. The HL-4 meat had lower cook loss compared to the other meats ( P < 0.05). HL supplementation increased C20:4n-6 concentration ( P < 0.05). HL-2 meat had higher total polyunsaturated fatty acids compared to the other groups (P < 0.05). The HL-2 and HL-4 meats had lower TBARS values ( P < 0.05) throughout the 5-day postmortem chill storage. Dietary inclusion of 2–4% hemp leaves improved carcass yield, fatty acids, and oxidative stability of goat meat without compromising other quality traits, suggesting its potential as a natural feed additive to enhance meat quality and shelf life.

Journal of Animal Science and Technology (JAST) is a peer-reviewed, open access journal publishing original research, review articles and notes in all fields of animal science. Topics covered by the journal include: genetics and breeding, physiology, nutrition of monogastric animals, nutrition of ruminants, animal products (milk, meat, eggs and their by-products) and their processing, grasslands and roughages, livestock environment, animal biotechnology, animal behavior and welfare.

This study investigated the influence of hemp leaves in concentrate diets on growth performance, nutrient digestibility, and intestinal morphology in goats