Poultry Science最新文献

{"title":"Whole-genome insights into a multidrug-resistant, biofilm-forming, and pathogenic Salmonella Umbilo isolate and molecular characterization of rare Salmonella serovars from poultry.","authors":"Seyyide Sarıçam İnce, Akın Ünal, Mehmet Akan","doi":"10.1016/j.psj.2026.107930","DOIUrl":"10.1016/j.psj.2026.107930","url":null,"abstract":"<p><p>Salmonellosis is one of the leading foodborne zoonoses worldwide, with contaminated poultry products representing a major source of human infection. This study characterized rare Salmonella serovars circulating in poultry flocks with respect to biofilm formation, virulence, antimicrobial resistance (AMR), CRISPR loci diversity, and genomic features. Salmonella isolates were conventionally isolated from drug swap samples and serotyped. Biofilm- (csgA, csgB, csgD, ompR, adrA, rpoS, and fimH) and virulence-associated genes (sipA, sipD, sopB, sopD, sopE, sopE2, sitC, sifA, ssaR, spvC, and pefA) were investigated. CRISPR loci and phenotypic AMR were examined. The Salmonella isolate, which exhibited the highest MAR index, was analyzed by whole-genome sequencing (WGS). Bioinformatic analyses were conducted to determine its plasmid, AMR, and virulence capacity. Thirty rare Salmonella serovars were identified including, Aba, Atento, Ball, Blegdam, Bonariensis, Bradford, Chandans, Fallowfield, Ferruch, Idikan, II (1,9,12:g,m,s,t:e,n,x), Inganda, Korbol, Leeuwarden, Menden, Naestved, Ohlstedt, Papuana, Petahtikve, Sandow, Schwarzengrund, Svedvi, Telaviv, Thompson, Tinda, Tsevie, Tumodi, Umbilo, Uppsala, and Vejle. CsgA-B-C (100.0%) and sipA (96.7%) were the most prevalent genes. S. Sandow harbored all examined genes. CRISPR2 locus (23.3%) was more prevalent than the CRISPR1 locus (3.3%). Resistance to streptomycin (56.7%) and sulfonamides (46.7%) was most common, whereas 40.0% of the isolates were MDR. WGS of the S. Umbilo isolate, which exhibited the highest MAR index (0.48), identified the IncHI2A plasmid (a key factor in horizontal transfer of AMR genes), 12 AMR genes (responsible for resistance to beta-lactams, aminoglycosides, phenicols, and lincosamides), and 181 virulence-associated genes (involved in adhesion, invasion, chemotaxis, intracellular survival, and environmental persistence). The detection of highly resistant and potentially pathogenic S. Umbilo, previously linked to a multinational foodborne outbreak in Europe, highlights its potential public health significance. MLST further proved useful for serovar prediction, with ST2014. Rare Salmonella serovars circulating in poultry flocks possess substantial virulence, biofilm-forming, and AMR potential. These findings highlight the importance of including rare serovars in surveillance and control programs to mitigate foodborne transmission and the spread of AMR.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107930"},"PeriodicalIF":4.5,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149169804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Baicalin modulates endoplasmic reticulum-Golgi homeostasis via targeting ATF6-GBF1 axis to alleviate copper-induced nephrotoxicity in duck.","authors":"Hongyu Shang, Wei Tang, Xueyan Dai, Xiaona Gao, Guoliang Hu, Huabin Cao, Chenghong Xing, Fan Yang","doi":"10.1016/j.psj.2026.107914","DOIUrl":"https://doi.org/10.1016/j.psj.2026.107914","url":null,"abstract":"<p><p>Copper (Cu) exposure caused by environmental contamination or dietary imbalance poses a potential threat to poultry health by inducing renal dysfunction and disrupting cellular homeostasis. Baicalin (BA), a natural flavonoid with antioxidant and anti-inflammatory properties, has shown renoprotective potential. However, whether and how BA alleviates Cu-induced nephrotoxicity remains unclear. Disruption of endoplasmic reticulum (ER)-Golgi trafficking impairs cellular homeostasis and may contribute to renal injury, but its role in Cu-induced kidney damage has not been fully defined. In this study, using duck in vivo and in vitro Cu exposure models, we found that Cu downregulated the Golgi structural protein GBF1 and disrupted ER-Golgi trafficking, leading to Golgi fragmentation, ER swelling, and ER stress activation via ATF6. Functional assays revealed that GBF1 knockdown further decreased the expression of Golgi structural and trafficking-related proteins and exacerbated ER stress, whereas ATF6 silencing partially reversed these molecular alterations. Moreover, our results provide evidence that BA can stably bind to ATF6, inhibit its activation and proteolytic cleavage, restore the expression of Golgi and trafficking-related proteins, and reduce ER stress, thereby maintaining organelle homeostasis. In summary, our results identify the GBF1-ATF6 axis as a key pathway in Cu-induced ER-Golgi dysregulation and nephrotoxicity, and provide mechanistic insight into the protective role of BA in restoring subcellular homeostasis.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107914"},"PeriodicalIF":4.5,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149165068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Economic impacts of longer lay cycle in Canada: Evidence across different housing systems and hen strains.","authors":"Maurice Doyon, Ousmane Z Traore","doi":"10.1016/j.psj.2026.107928","DOIUrl":"https://doi.org/10.1016/j.psj.2026.107928","url":null,"abstract":"<p><p>Recent advancements in genetics and management practices have enabled laying hens to sustain high productivity and egg quality for laying period of up to 80-100 weeks. However, despite these gains and evidence showing the adoption of longer lay cycles (LLC) in the United States and Europe, Canadian egg production remains largely anchored to a 51-week cycle, with laying rates exceeding 90% at culling. Producer hesitancy may reflect the absence of farm‑level economic analyses across bird strains and housing systems. This study addresses this gap by evaluating the economic impacts of LLC across aviary, enriched, and conventional systems using farm-level data from 20 commercial flocks across Canada, with lay cycle duration ranging from 50 to 67 weeks. We apply partial budgeting and econometric modeling to evaluate the impacts of LLC on profitability. Results indicate that on average, across housing systems and bird strains, each additional week beyond 51 weeks increases producer profit per dozen eggs sold by an average of 1.2%. Optimal length of lay is estimated at 62 weeks in current market and production conditions. Although based on a limited sample and not generalizable to the entire Canadian egg sector, these findings provide empirical evidence to Canadian egg producers on the potential economic viability of LLC across different housing system and bird strain combinations.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107928"},"PeriodicalIF":4.5,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Core developmental modules and microbial biomarkers associated with liver-gut axis maturation in Pekin ducks.","authors":"Suyun Liang, Meixi Lu, Yi Tang, Shuisheng Hou","doi":"10.1016/j.psj.2026.107926","DOIUrl":"https://doi.org/10.1016/j.psj.2026.107926","url":null,"abstract":"<p><p>The early post-hatch period is critical for the liver-gut axis maturation in Pekin ducks, yet the high-resolution multi-omics landscape remains unexplored. Using 195 ducks at 7, 14, and 21 days, we integrated phenotypic assessments with liver transcriptomics, targeted metabolomics (bile acids, pyrimidines, taurine), and cecum 16S rRNA sequencing. A DHAV‑3 infection model was employed to challenge the normal developmental trajectory, and machine learning was applied to identify microbial biomarkers. Ducklings transitioned from active hepatic proliferation to metabolic specialization, with reduced lipid droplets by day 21, alongside age-dependent enrichment of lipid transport and receptor tyrosine kinase signaling. Bile acids remodeled from early TCA/HCA elevation to TCDCA/taurine dominance at 21 days, while cecum microbiota shifted from Bacteroidota to Lactobacillales and Candidatus_Arthromitus. Following FDR correction (q < 0.05), multi‑omics integration identified Erysipelatoclostridium (degree = 430), Intestinimonas (degree = 428), and CYP2J2 (degree = 46) as the most highly connected nodes in the gene-genus association network. Virus infection disrupted this trajectory, suppressing iron/IgG and reversing bile acid and microbial patterns. A nested cross‑validation (5‑fold × 10 repeats) prediction model using three microbial genera (Alloprevotella, Anaerobiospirillum, Anaerofustis) achieved excellent discriminative performance (full‑data AUC = 0.956; nested CV mean AUC = 0.846 ± 0.073). Our findings reveal the temporal multi-omics landscape of the early-life liver-gut axis and provide a microbiota‑based framework for monitoring host status, offering novel targets for early nutritional programming and precision management in poultry.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107926"},"PeriodicalIF":4.5,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Species-dependent water and salt migration drives lipoprotein remodeling and quality formation during rapid curing of separated egg yolks.","authors":"Qianwei Cheng, Xue Luo, Tong Chen, Yue Che, Siting Huang, Yuanwei Yang, Luli Meng, Yuetong Zhao, Yuan Cheng","doi":"10.1016/j.psj.2026.107927","DOIUrl":"https://doi.org/10.1016/j.psj.2026.107927","url":null,"abstract":"<p><p>Rapid curing of separated egg yolks provides an efficient strategy for accelerating salted egg production; however, how species-dependent intrinsic yolk organization regulates small molecule migration and subsequent lipoprotein remodeling remains poorly understood. In this study, egg yolks separated from hen, duck, and sea duck eggs were used as model systems to elucidate the relationships among water and NaCl migration, lipoprotein structural evolution and quality formation during rapid curing. Water redistribution and NaCl accumulation followed distinct migration trajectories among poultry species throughout curing, resulting in different hydration environments and colloidal stability of the yolk matrix. These migration behaviors promoted progressive lipoprotein disassembly, protein conformational rearrangement and subsequent intermolecular reassembly, resulting in species-dependent gel network formation and textural characteristics. Principal component analysis (PCA) showed that, although curing progression was the dominant source of variation (PC1), poultry species contributed to the secondary variation (PC2), reflecting species-dependent physicochemical evolution during rapid curing. Correlation analysis further supported the close association among small molecule migration, lipoprotein remodeling, and quality formation during rapid curing, reinforcing the proposed mechanism linking migration behavior with structural reconstruction and functional development. This study establishes a mechanistic framework linking small-molecule migration, lipoprotein reconstruction and quality formation during rapid curing, providing theoretical guidance for species-specific processing optimization and the design of high-quality salted egg products.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107927"},"PeriodicalIF":4.5,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149166075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physiological and microbial responses to periodic drinking-water supplementation with Chenopodium ambrosioides extract in broiler chickens.","authors":"Shaza Y A Qattan, Elwy A Ashour, Ali O Osman, Samir A Mahgoub, Mayasar I Al-Zaban, Fatmah A Safhi, Amal S Altmimi, Mona Alharbi, Aisha M Bahatheq, Mohamed E Abd El-Hack","doi":"10.1016/j.psj.2026.107933","DOIUrl":"https://doi.org/10.1016/j.psj.2026.107933","url":null,"abstract":"<p><p>Phytogenic extracts may influence poultry performance through changes in systemic oxidative status and intestinal microbial populations. This study evaluated the effects of periodic Chenopodium ambrosioides extract (CAE) supplementation through drinking water on growth performance, carcass characteristics, serum biochemical and oxidative status, cecal bacterial populations, and microbiological stability of broiler meat. A total of 210 five-day-old Ross 308 chicks were randomly assigned to 3 groups: an unsupplemented control and 2 CAE treatments receiving 3 or 6 mL/L of drinking water every third day from d 5 to 34. The methanolic CAE contained 22.2 mg gallic acid equivalents/g of total phenolic compounds and 1.13 mg quercetin equivalents/g of flavonoids, with DPPH SC₅₀ values ranging from 15.66 to 81 mg/mL. CAE supplementation improved feed conversion ratio, with the lowest value observed in supplemented birds compared with the control (1.28 vs. 1.47; P = 0.026), while feed intake decreased without a significant change in body weight. Water intake was also reduced by CAE supplementation (P = 0.034). Carcass responses were selective, with lower relative weights of the heart, gizzard, and spleen and increased abdominal fat deposition in CAE-treated birds (P < 0.05). At 6 mL/L, CAE increased serum HDL concentration (31.46 vs. 28.29 mg/dL; P = 0.002), reduced urea (34.12 vs. 41.61 mg/dL; P = 0.031) and malondialdehyde concentrations (3.31 vs. 3.62; P = 0.001), and increased glutathione S-transferase activity and reduced glutathione levels (P < 0.05). These responses indicate changes in systemic biochemical and oxidative status following CAE supplementation. In the cecum, CAE produced dose-dependent reductions in total bacterial and coliform populations, accompanied by increased Lactobacillus counts (P < 0.001). Meat microbiological stability was also improved, as indicated by lower aerobic plate counts on d 10 in birds receiving 6 mL/L CAE (P < 0.001). Overall, periodic supplementation with C. ambrosioides extract through drinking water, particularly at 6 mL/L, was associated with improved feed efficiency and coordinated changes in systemic oxidative status and measured cecal bacterial populations, together with reduced microbial counts in broiler meat.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107933"},"PeriodicalIF":4.5,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149184036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Puerarin improved meat quality via the gut-muscle axis mediated by liver metabolites in chicken.","authors":"Daozi Zhaxi, Yuxi Zhang, Yi Qing, Yuding Zhang, Dongmei Yang, Chunlin Yu, Chaowu Yang, Zhixiong Li","doi":"10.1016/j.psj.2026.107917","DOIUrl":"10.1016/j.psj.2026.107917","url":null,"abstract":"<p><p>Improving the meat quality of chicken is a premier objective driven by surging global consumer demand. As a natural isoflavone derivative, Puerarin (PUE) possesses extensive metabolic and regulatory potential, but its exact mechanism in reshaping avian meat quality traits remains poorly understood. This study investigated the effects of PUE supplementation (0.08%) on Daheng chickens over a 70-day rearing period using metagenomics and untargeted LC-MS metabolomics. The results demonstrated that PUE significantly reduced post-mortem drip loss and cooking loss, and enhanced the 45-min post-mortem redness (a*) of leg muscle, while muscle fiber diameter and intramuscular fat (IMF) content remained statistically unaltered. Metagenomic and cecal metabolomic analyses revealed that PUE enriched key microbial consortia, notably Methanobrevibacter, Candidatus_Pelethomonas, Catenibacillus, and Candidatus_Scybalocola, which positively synchronized with the accumulation of enteric antioxidants such as Equol, Puerarin, 6''-O-Malonyldaidzin, and Liquiritin. Liver metabolomics, Mantel tests and mediation analysis identified Candidatus_Scybalocola as a key genus, proving that the gut-driven signals were channeled through adenosine monophosphate (AMP), Fahfa (9:0/18:3), 6''-O-Malonylglycitin, and 5-Hydroxy-3,6,7,8,3',4'-Hexamethoxyflavone. Intramuscularly, these upstream metabolic realignments culminated in the deposition of Spermidine, endogenous Lipoxin B4, and phytogenic flavonoids (Gossypetin 8-Glucuronide 3-Glucoside and Tricin 7-Diglucuronoside). These localized molecular hubs established a powerful barrier that mitigated post-mortem oxidative leakage and stabilized myofibrillar protein frameworks against thermal shrinkage. The overall optimization of water-holding traits highlights PUE as an effective nutritional intervention to enhance broiler meat quality through gut-muscle axis.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107917"},"PeriodicalIF":4.5,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149138070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A point mutation in duck plague virus gB enhances viral fusogenicity and intercellular dissemination via SNAP25-mediated membrane fusion.","authors":"Linjiang Yang, Mao Du, Lingfeng Jiang, Zhentao Cheng, Ming Wen, Guilan Wen, Anchun Cheng","doi":"10.1016/j.psj.2026.107920","DOIUrl":"10.1016/j.psj.2026.107920","url":null,"abstract":"<p><p>Duck plague virus (DPV) is an alphaherpesvirus that causes significant economic losses to the poultry industry. Glycoprotein B (gB) is the core fusogen mediating membrane fusion during viral entry and cell-to-cell spread, yet the regulatory mechanisms governing gB-induced cell fusion in DPV remain poorly understood. In this study, we identified a single alanine-to-valine substitution at residue 942 of DPV gB (A942V) that unleashes the fusogenic potential of gB, leading to extensive syncytium formation in duck embryo fibroblasts. The A942V mutation significantly enhanced viral attachment, entry, and intercellular spread through fusion-mediated cytoplasmic channels, as revealed by transmission electron microscopy. In vivo, the mutant strain showed moderately increased pathogenicity-with survival rates of 60% versus 70% for the parental strain-without fundamentally altering the overall disease course. Proteomic profiling identified synaptosome-associated protein 25 (SNAP25) as a host factor markedly upregulated in DPV-A942V-infected cells. Mechanistically, the A942V mutation strengthened the binding affinity between gB and SNAP25, as corroborated by co-immunoprecipitation and molecular docking analyses (binding free energy: -82.92 kcal/mol; confidence score: 0.9478). Functional studies revealed that SNAP25 alone is sufficient to induce cell fusion, and that both its N- and C-terminal domains support fusion activity, whereas the middle region is functionally dispensable. SNAP25 overexpression enhanced, whereas knockdown reduced, viral proliferation and cell-to-cell spread without affecting viral attachment or entry. Collectively, these findings establish Ala942 of DPV gB as a critical inhibitory determinant of cell fusion and identify SNAP25 as a critical host dependency exploited by DPV to promote intercellular dissemination. Our study provides new insights into the molecular mechanisms of herpesvirus-induced cell fusion and highlights SNAP25 as a potential antiviral target for controlling DPV infection.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107920"},"PeriodicalIF":4.5,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Longitudinal study assessing antimicrobial usage in broiler production cycles in northern Vietnam in 2022 to 2023.","authors":"Chen Xin, Trang Nguyen, Quoc Hung Nguyen, Saira Butt, Huong Quynh Luu, Hoa Thi Thanh Pham, Anne Conan, Ngoc Thi Pham, Dirk Pfeiffer, Damer Blake, Fiona Tomley, Priscilla F Gerber, Beatriz Calvo-Urbano, Guillaume Fournié, Ludovic Pelligand","doi":"10.1016/j.psj.2026.107918","DOIUrl":"https://doi.org/10.1016/j.psj.2026.107918","url":null,"abstract":"<p><p>Antimicrobial drugs (AMDs) are commonly used in chicken production in Vietnam for both preventive (prophylactic) and therapeutic purposes. Characterizing how the frequency of antimicrobial usage (AMU) changes from flock placement to harvest, varies by purpose, and may be influenced by production stage and mortality levels, can guide antimicrobial stewardship interventions to mitigate the risk of antimicrobial resistance (AMR) in broiler production. We investigated daily AMU and mortality patterns in production cycles of slow-growing broiler chicken flocks raised on 60 farms in two provinces (Ha Noi and Bac Ninh) in northern Vietnam at the end of 2022 and the beginning of 2023. The association between the daily probability of AMU and mortality risk was evaluated using generalized additive mixed models (GAMMs). The dynamic process of initiating a new treatment, and the expected duration of that episode, were further assessed using a two-state semi-Markov process (SMP) within a Bayesian framework. A total of 569 treatment events (70.5% preventive vs. 29.5% therapeutic) were recorded across all 60 monitored cycles. A median value of 186.1 mg/Population Correction Unit (PCU) AMDs was used for prophylaxis, while 116.7 mg/PCU was used for therapeutic treatment per production cycle. The most frequently administered AMDs for preventive treatments were colistin (23.2%), amoxicillin (19.2%), and doxycycline (11.7%). Therapeutic treatments mostly involved doxycycline (26.8%), florfenicol (17.9%), and amoxicillin (13.7%). The main effect of within-flock mortality was not significant, but the interaction between mortality and broiler age was associated with AMU both in the case of preventive and therapeutic AMU (p-value <0.05), suggesting that the effect of mortality on AMU may have varied depending on the broiler age. Broiler age was strongly and non-linearly associated with AMU (p<0.05), with distinct temporal patterns for preventive and therapeutic use. At the start of a production cycle, initiation of preventive treatment was substantially more likely than initiation of therapeutic treatment (day 0: risk ratio [RR] = 8.6), and prophylactic treatment remained dominant during the early cycle (RR > 2 before day 22). These findings indicate that preventive treatment is the primary driver of AMU during the early cycle, highlighting the need for stewardship interventions at this stage, focused on reducing non-essential prophylactic use and promoting lower-risk alternatives.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107918"},"PeriodicalIF":4.5,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149195929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the potential growth and body composition of the Cobb MV x500 genotype.","authors":"N S B M Atapattu, K B Nelson, M T Kidd, R M Gous","doi":"10.1016/j.psj.2026.107911","DOIUrl":"10.1016/j.psj.2026.107911","url":null,"abstract":"<p><p>The potential growth and body composition of modern broiler genotypes must be periodically re-evaluated to quantify the effects of continued genetic selection and to provide the information required for predictive growth models. This study characterized the growth potential of male and female Cobb MV × 500 broilers reared under non-limiting conditions from hatch to 105 d of age. Two hundred birds of each sex were fed ad libitum using a four-phase feeding program, and body weight, feather growth, physical body components, and chemical composition were measured serially throughout the growing period. Growth after feed withdrawal (empty BW) was described using the Gompertz function, and allometric relationships between body protein and the chemical and physical components of the body were determined. Males attained a higher mature BW and body protein weight than females, whereas females deposited proportionally more lipid. Mature empty BW were estimated to be 8.12 and 6.29 kg for males and females, respectively. Rates of maturing of the feather-free body were similar between sexes and comparable with those reported for contemporary broiler strains. Unusually, feather growth matured more slowly than the feather-free body. The hypothesis that, within a sex, all chemical and physical components of the body other than feathers could be described using a common rate of maturing was corroborated by the evidence presented. Water and lipid deposition differed markedly between sexes, whereas protein and ash contents remained relatively constant throughout growth. The resulting Gompertz and allometric coefficients provide a biologically consistent description of growth and body composition in this genotype and demonstrate that genetic improvement in modern broilers has been achieved primarily through increased mature size rather than major changes in developmental rate. These parameter estimates will assist in improving the prediction of nutrient requirements, feed intake, and changes in carcass composition in simulation models used for nutritional and management decision-making.</p>","PeriodicalId":20459,"journal":{"name":"Poultry Science","volume":"105 12","pages":"107911"},"PeriodicalIF":4.5,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149138118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}