Livestock Science最新文献

{"title":"Feed intake, ruminal parameters, milk production and economy in Holstein cows fed reduced forage or non-forage emergency diets","authors":"C.F. Børsting ,&nbsp;D.W. Olijhoek ,&nbsp;A.L. F. Hellwing ,&nbsp;K.M. Moyes ,&nbsp;S. Østergaard ,&nbsp;M.R. Weisbjerg ,&nbsp;P. Lund ,&nbsp;B.M. Raun ,&nbsp;B.A. Røjen ,&nbsp;N.B. Kristensen","doi":"10.1016/j.livsci.2025.105825","DOIUrl":"10.1016/j.livsci.2025.105825","url":null,"abstract":"<div><div>We evaluated how to maintain dairy herds in a productive state after extreme drought episodes via substituting high quality forage (corn and grass-clover silages) with concentrate and straw. Ninety Holstein cows were allocated to a randomized trial for 11 weeks. The planned roughage-to-concentrate ratios (% of dietary DM) of the diets were: 51:49, 30:70, and 9:91. Two different concentrate palettes were used to substitute forage representing domestic (RGB) and globally (COS) available feedstuffs. The concentrate mixture RGB contained only feedstuffs that can be produced in the European Union. The RGB mixture contained starch from the feedstuffs ground barley and NaOH-treated whole wheat kernels, fibers from dried beet pulp and distiller’s dried grains (DDGS) and protein from rapeseed cake and DDGS. The concentrate mixture COS was based on globally available feedstuffs and contained starch from corn (ground kernels), fiber from soyhulls, and protein mainly from soybean meal. Treatments did not affect concentrate intake in milking robots, whereas intake of the partially mixed rations was 0.6 kg DM per day less with RGB when compared to COS. Milk fat concentrations were severely reduced with greater concentrate intake and reflected ruminal molar proportions of acetate to propionate. The study showed that it is possible to use concentrate-based emergency rations to keep dairy herds milking after severe drought episodes with a shortage of forage, however, the loss in milk fat yield implies that farmers should prioritize forage, even when prices are up to 2.5 to 3.3 times the standard production cost.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"302 ","pages":"Article 105825"},"PeriodicalIF":1.9,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precision feeding in gestating sows: a retrospective analysis of lysine intake and pregnancy outcomes","authors":"P. Langendijk ,&nbsp;A.K. Agyekum ,&nbsp;F. Simard ,&nbsp;M. Richer-Lanciault","doi":"10.1016/j.livsci.2025.105824","DOIUrl":"10.1016/j.livsci.2025.105824","url":null,"abstract":"<div><div>From day 30 of gestation, 288 mixed parity sows were fed a diet varying in the inclusion of lysine and other amino acids, to meet changing requirements throughout gestation more closely (precision feeding). Lysine inclusion for precision fed sows was varied by parity group and was altered every few days by blending two diets differing in lysine at varying ratios. As a reference, 280 mixed parity sows were fed a single gestation diet consistent in lysine and well above requirements (NRC 2012). To investigate the role of lysine intake in prenatal development, standardised ileal digestible (SID) lysine requirements were estimated retrospectively based on realised maternal gain and litter weights at farrowing. SID Lysine excess was calculated over day 30 to 80 of gestation, the period of accelerated placenta growth, and defined as lysine intake minus requirements. SID Lysine excess was lower for precision fed sows, and sows with lowest lysine excess (1 g/d or less) had lower foetal survival (90.8 % vs 93 to 95 %), more mummies per litter (0.6 vs 0.2 to 0.3), and more litters with at least one mummy (38 % vs 12 to 21 %), compared to sows with SID lysine excess of 1 g/d and more. In conclusion, when feeding amino acids closer to requirements, in some sows this may result in feeding under requirements, potentially compromising foetal development. This study provides a previously undefined safety margin for SID lysine of 1.5 g/d, which can be used to formulate gestation diets and feeding strategies.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105824"},"PeriodicalIF":1.9,"publicationDate":"2025-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic correlations between carcass traits measured by ultrasonography and semen quality traits in Nellore cattle incorporating genomic information","authors":"Camila S. Mussi ,&nbsp;Gabriel C. Medeiros ,&nbsp;Rafael Espigolan ,&nbsp;Fernando Baldi ,&nbsp;Marcio R. Silva ,&nbsp;José D. Guimarães ,&nbsp;Elisangela C. Matos ,&nbsp;Joanir P. Eler ,&nbsp;Tamires Miranda Neto ,&nbsp;José Bento S. Ferraz ,&nbsp;Luiz F. Brito","doi":"10.1016/j.livsci.2025.105820","DOIUrl":"10.1016/j.livsci.2025.105820","url":null,"abstract":"<div><div>Nellore cattle (<em>Bos taurus indicus</em>), the predominant beef cattle breed raised in Brazil, has substantial economic importance in the global beef market. Ultrasonography is commonly used to measure carcass traits, which facilitate the genetic evaluation of live animals and provides indicators of meat quality. Male reproductive efficiency assessed by semen quality and scrotal circumference traits directly influences farm profitability. This study estimated variance components and genetic correlations between ultrasound-based carcass and semen quality and scrotal circumference traits in Nellore cattle. We used a dataset of 116,011 animals with phenotypic records, 13,632 genotyped animals, and a pedigree with 635,175 animals. Heritability estimates for scrotal circumference at 18 and 24 months were moderate (0.39 ± 0.008 and 0.38 ± 0.02, respectively). Semen quality traits, including motility, vigor, and mass activity were found to be lowly heritable with estimates ranging from 0.03 ± 0.01 to 0.05 ± 0.01. The heritability estimates for sperm defects were also low and ranged from 0.01 ± 0.007 to 0.12 ± 0.02. Carcass traits, including ribeye area and rump fat thickness, were moderately heritable (0.34 ± 0.05 and 0.39 ± 0.06), while subcutaneous fat thickness had a heritability of 0.18 ± 0.04. Genetic correlations between carcass with semen quality and scrotal circumference traits were of low to moderate magnitude and unfavorable. These findings indicate that carcass traits can be improved through genetic selection and the generally low genetic correlations with sperm quality traits and scrotal circumference traits suggest that selection for improved carcass traits, measured using ultrasonography technology, is expected to have minimal impact on semen quality. Therefore, simultaneous selection for both trait groups is recommended to ensure optimal long-term genetic improvement in Nellore cattle breeding programs.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105820"},"PeriodicalIF":1.9,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of phytase supplementation on broiler chickens fed nutrient-deficient diets","authors":"Samuel Oliveira Borges ,&nbsp;Tiago Goulart Petrolli ,&nbsp;Melissa Izabel Hannas ,&nbsp;Romário Duarte Bernardes ,&nbsp;Carlos Henrique de Oliveira ,&nbsp;Kelly Morais Maia Dias ,&nbsp;Bruno Figueiredo de Almeida ,&nbsp;Lucimauro da Fonseca ,&nbsp;Alex Filipe Ramos de Sousa ,&nbsp;Arele Arlindo Calderano","doi":"10.1016/j.livsci.2025.105823","DOIUrl":"10.1016/j.livsci.2025.105823","url":null,"abstract":"<div><div>This study aimed to evaluate the effects of different inclusion levels of phytase on the performance, body composition, blood parameters, and bone characteristics of broilers fed reduced-nutrient diets. The experiment was conducted using 1400 male broilers, allocated to seven treatments with ten replicates and twenty birds per experimental unit, in a completely randomized design. The experimental treatments were: positive control, formulated to fully meet the birds’ nutritional requirements; negative control 1 (NC1), negative control 2 (NC2) and negative control 3 (NC3), formulated with nutrient reductions according to the phytase nutrient release matrix but without enzyme supplementation; and NC1, NC2 and NC3 supplemented with 500, 750 and 1000 FTU of phytase. Phytase supplementation improved (<em>P</em> &lt; 0.05) body weight gain, feed conversion ratio, and final body weight compared to the negative controls, restoring these parameters to levels comparable with the positive control, even in diets simultaneously reduced in available phosphorus (P), total calcium (Ca), total sodium, metabolizable energy, crude protein, and digestible amino acids. Improvements were also observed in serum Ca and P levels, as well as in bone indicators, including the Seedor index, bone breaking strength, and ash and magnesium concentrations, matching those of the positive control (<em>P</em> &lt; 0.05). Phytase supplementation further enhanced body composition, with greater deposition of lean tissue, protein, and bone in supplemented birds (<em>P</em> &lt; 0.05). The main contribution of this study is the confirmation of phytase’s effectiveness as a nutritional tool in challenging diets, demonstrating its capacity to recover performance and bone quality, with benefits that extend beyond phosphorus utilization.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105823"},"PeriodicalIF":1.9,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Managing without pharmaceutical zinc in Danish pig production – insights from farmers and veterinarians","authors":"Hanne Kongsted,&nbsp;Eimear Theresa Mc Loughlin","doi":"10.1016/j.livsci.2025.105822","DOIUrl":"10.1016/j.livsci.2025.105822","url":null,"abstract":"<div><div>In June 2022, Danish authorities implemented the EU ban on ‘pharmaceutical levels of zinc oxide’ (pZnO) in pig herds to protect the environment from pollution from heavy metals. Following the ban, an increased use of antibiotics was seen, especially for treating post-weaning diarrhoea.</div><div>The study used joint semi-structured interviews with farmers (<em>n</em> = 10) and vets (<em>n</em> = 8) to explore the challenges encountered in Danish pig herds and the background for the increased use of antibiotics following the ban. Interviews were carried out between January and April 2024.</div><div>Interviewees explained how diarrhoea, general unthriftiness, increased use of antibiotics and problems with antibiotic resistance were often the consequences of not providing pZnO. The most common measures to protect pigs from postweaning diarrhoea were changes in feeding management to ensure a steady feed intake and to avoid high levels of protein. However, in many cases such changes did not offset the negative effects, and some herds continuously struggled with unthrifty pigs. Surprisingly, most vets could not explain the possible reason that some herds were relatively unaffected whilst others experienced severe problems.</div><div>The study sheds light on the restrictive systemic conditions in modern Danish pig farming and how they affect the possibilities for adapting to societal demands. Many agreed that extensive management measures like lowered stocking density and increased weaning age might enable weaning without pharmaceuticals, but these measures were generally considered too expensive. In addition to increased disease occurrence, the increased use of antibiotics was explained by regulatory frameworks and intentions to support a ‘smoothly running production’.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105822"},"PeriodicalIF":1.9,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of timing and duration of stepwise vitamin–mineral premix withdrawal on welfare indicators and trace mineral excretion in broilers","authors":"S. Siahpour ,&nbsp;M.A.Karimi Torshizi ,&nbsp;O. Jangjou ,&nbsp;H. Saleh","doi":"10.1016/j.livsci.2025.105821","DOIUrl":"10.1016/j.livsci.2025.105821","url":null,"abstract":"<div><div>Trace mineral supplementation via vitamin–mineral premixes (VMP) is essential for broiler health and productivity but may contribute to environmental pollution through excessive mineral excretion. This study investigated the effects of time-based VMP withdrawal at different production stages on growth performance, bone mineralization, immune function, antioxidant capacity, welfare indicators, and zinc and copper excretion in broilers. A total of 500 one-day-old male Ross 308 chicks were allocated to five dietary treatments (five replicates per treatment; 20 birds/replicate) in a completely randomized design over 42days. Treatments consisted of a control group (VMP fed for 42 days) and four time-dependent withdrawal groups, where VMP was removed for the final 7, 14, 21, and 28 days of the trial. Growth performance, tibia characteristics, leg condition, serum immunoglobulins (IgM, IgG, IgA), cytokines (IL-10, IL-6, IL-1β), antioxidant enzymes (CAT, SOD, GPx), total antioxidant capacity, malondialdehyde (MDA), and fecal mineral excretion were measured. Data were analyzed using a general linear model with Tukey’s test (<em>P</em> &lt; 0.05) Results showed that earlier VMP withdrawal impaired growth, bone integrity, immunity, and antioxidant status while increasing feed conversion ratio, pro-inflammatory cytokines, MDA levels, and gait abnormalities. However, zinc and copper excretion decreased progressively as withdrawal occurred earlier. These findings suggest that strategically timed VMP withdrawal during the final production phase may reduce environmental impact without compromising broiler health, offering a practical and sustainable mineral management strategy.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105821"},"PeriodicalIF":1.9,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145057254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of black soldier fly (Hermetia illucens) larvae oil feed inclusion on growth performance and fecal microbiome development in post-weaning pigs","authors":"Matteo Buffoni ,&nbsp;Marco Viveen ,&nbsp;J Arjan GM De Visser ,&nbsp;Lapo Mughini-Gras ,&nbsp;Rob JL Willems ,&nbsp;Anita C Schürch ,&nbsp;Jannigje G Kers","doi":"10.1016/j.livsci.2025.105819","DOIUrl":"10.1016/j.livsci.2025.105819","url":null,"abstract":"<div><div>Post-weaning (PW) is a stressful period in the early life of growing pigs. Changes in diet may cause a shift in microbiome composition of the gastrointestinal tract (GIT), with potential effects on piglet health. Here, we evaluate the effect of black soldier fly larvae (BSFL) oil, as a sustainable nutrient source, on growth performance and fecal microbiome composition in PW pigs. Two trials were conducted, with Trial 1 including 60 piglets, of which 40 were sampled for microbiome analysis, and Trial 2 involving 160 piglets, of which 122 were sampled. All piglets were approximately 21 days old, Topigs/Pietrain crossbreed, weighed over 5 kg, and both trials lasted 39 days post-weaning. To assess the impact of BSFL oil blend on microbiome composition, 16S rRNA gene amplicon sequencing was performed on fecal samples collected on day 11 and 26 in Trial 1, and day 11 and 42 in Trial 2. No direct effects of BSFL oil blend implementation were observed on pig general performance in terms of body weight (BW), average daily gain (ADG) and gain-to-feed ratio (G). Moreover, no difference in microbiome development was observed with BSFL oil blend relative to soy and palm kernel oil. These results indicate that BSFL oil is a valid alternative nutrient source for weaned pigs, as both performance and microbiome are unaffected.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105819"},"PeriodicalIF":1.9,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145057259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbon and nitrogen footprints of Northern Chinese sheep and goat in the context of “Carbon Neutrality”","authors":"Fan Jiao ,&nbsp;Zhenyu Liu ,&nbsp;Hua Li","doi":"10.1016/j.livsci.2025.105818","DOIUrl":"10.1016/j.livsci.2025.105818","url":null,"abstract":"<div><div>The goals of carbon neutrality and environmental sustainability are driving the global transition to a low-carbon and low-nitrogen economy. As a key component of agriculture, livestock and poultry farming is a significant source of carbon and nitrogen emissions. Specifically, among meats products, ruminant-derived meats have the highest carbon and nitrogen footprints. However, a systematic study on the carbon and nitrogen footprints of sheep remains underexplored. This study aims to address this gap by conducting a detailed assessment of the carbon and nitrogen footprints of goats and sheep across different farming modes in North China, employing a full life cycle assessment (LCA) approach. The LCA includes emissions from feed production, enteric fermentation, manure management, and energy consumption. The results show that the average carbon footprint of sheep is 19.10 kg CO₂-eq/kg carcass weight (CW), slightly higher than the 18.9 kg CO₂-eq/kg CW for goats. In contrast, sheep have an average nitrogen footprint of 127 g N-eq/kg CW, lower than the 191 g N-eq/kg CW for goats. Emissions decrease as production scales increase, with sheep generally showing a lower overall environmental impact. This reduction stems from three key factors: higher feed conversion efficiency in mixed systems; improved manure management lowering methane from anaerobic decomposition compared to unmanaged grazing manure; and reduced emissions from feed cultivation, as optimized feed composition and lower overall consumption in mixed systems decrease fertilizer and energy use during crop growing. These findings not only provide valuable insights into the environmental sustainability of sheep farming but also offer practical emission reduction strategies. By linking these findings to global carbon neutrality goals, this study contributes to the advancement of sustainable livestock farming and environmental stewardship in the long term.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105818"},"PeriodicalIF":1.9,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of weaning age on physiological, behavioral, and performance indicators of welfare in weaned piglets","authors":"Bianca F. Metallo,&nbsp;Lucas C. Spetic Da Selva,&nbsp;Arieli D. Da Fonseca,&nbsp;Richard T. Niblett,&nbsp;Edgar O. Aviles-Rosa","doi":"10.1016/j.livsci.2025.105816","DOIUrl":"10.1016/j.livsci.2025.105816","url":null,"abstract":"<div><div>For the past 25 years, the United States and European Union swine industries have differed in their welfare standards related to weaning age. Thus, the optimal weaning age for piglets continues to be a subject of debate. The objective of this study was to evaluate the effect of weaning piglets at 3 and 4 weeks of age on a set of physiological, behavioral, and performance indicators of welfare. Sixteen litters (N = 160 piglets) were assigned to be weaned at approximately 3 (n = 80) or 4 (n = 80) weeks of age based on the sow’s farrowing date and balancing for sow parity. At weaning, piglets were blocked by weight and randomly housed in pens of 5 piglets. Blood samples were collected prior to weaning and at 24 hours and 7 days post-weaning. A subset of pens was video recorded for the first 48 hours post-weaning, and weight gain and feed intake were monitored for 28 days post-weaning. Piglets weaned at 3 weeks showed a higher neutrophil-lymphocyte ratio (<em>P</em> &lt; 0.001) at 24 hours post-weaning, and displayed less feeding behavior (<em>P</em> &lt; 0.05) during the first 24 hours post-weaning, compared to piglets weaned at 4 weeks. Overall, piglets weaned at 3 weeks had lower average daily feed intake (<em>P</em> &lt; 0.001) and lower average daily gain (<em>P</em> &lt; 0.001) during the 28-day nursery phase. Our results indicate that weaning piglets at 4 weeks of age, as opposed to 3 weeks, has a positive impact not only on their performance, but also on behavioral and physiological indicators of welfare.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105816"},"PeriodicalIF":1.9,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145045161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of beta-mannanase supplementation on growth performance, digestibility, intestinal morphometry, and cecal microbiota in broiler chickens","authors":"Bárbara Vitória Marçal ,&nbsp;Raully Lucas Silva ,&nbsp;Larissa Pereira Maria ,&nbsp;Renan dos Santos Araújo ,&nbsp;Leilane Rocha Barros Dourado ,&nbsp;Marcos Kipper da Silva ,&nbsp;Nilva Kazue Sakomura","doi":"10.1016/j.livsci.2025.105817","DOIUrl":"10.1016/j.livsci.2025.105817","url":null,"abstract":"<div><div>The β-mannans present in the fibrous portions of vegetables are associated with increased gastrointestinal viscosity, delayed gastric emptying, and reduced nutrient digestibility. Dietary supplementation with exogenous β-mannanase could offer an alternative to mitigate the adverse effects of this anti-nutritional factor, given its resistance to most chemical and physical processes used for treatment and inactivation. This study evaluated the effects of β-mannanase supplementation on growth performance, intestinal morphometry, cecal microbiota, and digestibility in broiler chickens. Treatments were as follows: PC positive control (basal diet), NC negative control (basal diet with a reduction of 36 kcal/kg of metabolizable energy), and NC+β_m: negative control with the addition of β-mannanase. The β-mannanase supplementation (NC+βm) resulted in greater digestible energy from d 0 to 21 compared to PC and NC. At d 22, NC+βm exhibited greater digestible energy (<em>P</em> = 0.043) and villus-to-crypt ratio (<em>P</em> = 0.007) compared with PC in the duodenum, suggesting enhanced nutrient absorption. At 43 d, broiler chickens on NC+β_m had lower (<em>P</em> &lt; 0.001) villus height and crypt depth compared with PC and NC in the duodenum. Across all indices, alpha diversity of the cecal microbiota, except for Simpson's index and Pielou's evenness, was greater (<em>P</em> &lt; 0.01) in 43 d on the β-mannanase diet than at 22 d, indicating a potential positive modulation of gut microbial ecology over time. Based on the results, β-mannanase supplementation can be considered a nutritional strategy for broiler chickens, with positive effects on intestinal morphometry, cecal microbiota, and the apparent digestibility of gross energy.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"301 ","pages":"Article 105817"},"PeriodicalIF":1.9,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145019823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}