Animal最新文献

{"title":"The effects of incorporating sprouted barley in diets of high-yielding dairy cows on production, efficiency, and nutrient digestibility","authors":"U. Moallem ,&nbsp;J. Shpirer ,&nbsp;L. Livshits ,&nbsp;T. Alon ,&nbsp;Y. Shaani ,&nbsp;H. Kamer ,&nbsp;Y. Portnik ,&nbsp;H. Leibovich","doi":"10.1016/j.animal.2025.101598","DOIUrl":"10.1016/j.animal.2025.101598","url":null,"abstract":"<div><div>The sprouted system is the process of growing grains hydroponically in trays. Recently, there has been interest in using sprouted grains as feed for ruminants. The objective of this study was to determine how including sprouted barley in dairy cow rations affects performance, nutrient digestibility, and efficiency. Forty-two mid-lactation Israeli Holstein dairy cows were divided into two treatment groups (n = 21) and fed for 12 weeks: (1) Control (<strong>CTL</strong>) – a typical milking cow ration contained 38.9% forage (DM basis) and (2) Sprouted Barley (<strong>SB</strong>) – a diet contained 33.7% forage, and 11.5% (DM basis) SB. Diets were fed as a total mixed ration. Milk yields and BW were recorded daily, and milk samples were taken for milk solid concentration. Rumen and faecal samples were taken for volatile fatty acid and digestibility measurements, respectively, and blood samples were taken for blood metabolite analysis. Milk yield was 4.1% higher (45.7 and 43.9 kg/d, respectively; <em>P</em> &lt; 0.001) in the SB cows. Milk fat concentrations and yields were lower in the SB cows than in the CTL cows (3.82 and 4.10%, <em>P</em> &lt; 0.001, and 1.69 and 1.77 kg/d, <em>P</em> = 0.04, respectively). Milk protein concentration was higher in the SB cows with no difference in protein yield, and the milk urea nitrogen was 17.0% lower in the SB cows (<em>P</em> &lt; 0.001). The 4% fat-corrected and energy-corrected milk yields did not differ between treatments, and the DM intake (<strong>DMI</strong>) tended to be higher in the CTL (<em>P</em> = 0.08). The milk-to-DMI ratio was 6.3% higher in the SB cows (<em>P</em> &lt; 0.001), with no differences in other efficiency calculations. The rumen ammonia concentration was 21% lower in the SB cows (<em>P</em> = 0.006), and rumen acetate, propionate, and total volatile fatty acids were higher in the CTL cows. Apparent total tract digestibility of DM, organic matter, and CP was higher in the SB cows (<em>P</em> = 0.003) and tended to be higher for NDF (<em>P</em> = 0.10). Lower blood levels in triglycerides, urea, and cholesterol were observed in the SB cows (<em>P</em> = 0.04). In summary, sprouted barley is a potential feedstuff; however, further research is needed to determine an accurate nutritional value of sprouted barley and to fine-tune the optimal amount in the high-yielding dairy cow ration. This essential knowledge is required to reliably determine the economic viability of using sprouts in ruminants’ nutrition.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 8","pages":"Article 101598"},"PeriodicalIF":4.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review: Exploring correctness, usefulness, and feasibility of potential physiological operational welfare indicators for farmed insects to establish research priorities","authors":"M.G. Johnson ,&nbsp;M. Barrett","doi":"10.1016/j.animal.2025.101501","DOIUrl":"10.1016/j.animal.2025.101501","url":null,"abstract":"<div><div>While insects are already the largest group of terrestrial food and feed livestock animals in terms of absolute number of individuals, the insect farming industry is expected to continue growing rapidly in order to meet the nutritional demands of the human population during the 21st century. Accordingly, consumers, producers, legislators, and industry-adjacent researchers have expressed interest in further research and assessment of farmed insect welfare. Operational indicators of animal welfare are those that can be used to putatively assess the welfare of animals in the absence of true indicators of affective state (e.g., valenced/emotional state) and are commonly used for farmed vertebrate livestock species; however, significant behavioral and physiological differences between vertebrates and insects means these indicators must be examined for their correctness, usefulness, and feasibility prior to use with insect livestock. The most valuable operational welfare indicators would (1) correctly correspond to the insect’s putative welfare state; (2) provide useful information about what is affecting the insect’s welfare; and (3) be feasible for deployment at a large scale on farms. As there are many possible indicators that could be further researched in insects, evaluating the likely correctness, feasibility, and usefulness of these indicators in insects will allow researchers to prioritize which indicators to investigate first for use on farms. Thus, in this review, we explore whether physiological or somatic indicators of farmed vertebrate welfare, including whole-body, immune, neurobiological, and respiratory/cardiac indicators, may be correct, feasible, and useful for assessing farmed insect welfare. We review insect physiological systems, as well as any existing, welfare-relevant data from farmed or closely related insects. We end by proposing a priority list for physiological, operational welfare indicators that are most likely to correctly, usefully, and feasibly assess farmed insect welfare, which may guide indicator validation research priorities for insect welfare scientists.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 ","pages":"Article 101501"},"PeriodicalIF":4.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144054820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating eQTL and genome-wide association studies to uncover additive and dominant regulatory circuits in pig uterine capacity","authors":"Z. Xu ,&nbsp;H. Zeng ,&nbsp;J. Teng ,&nbsp;X. Ding ,&nbsp;J. Li ,&nbsp;Z. Zhang","doi":"10.1016/j.animal.2025.101599","DOIUrl":"10.1016/j.animal.2025.101599","url":null,"abstract":"<div><div>Uterine capacity is critical to the economic value of pigs. Exploring the genetic mechanisms that underlie uterine capacity can provide vital insights for pig breeding programmes. Here, we used a mixed model including additive and dominance effects to conduct genome-wide association analysis followed by cross-population meta-analyses for uterine capacity in 8 782 pigs from three pig breeds across nine populations. We identified 192 lead single−nucleotide polymorphisms (<strong>SNPs</strong>) with additive-specific effects, 236 lead SNPs with dominant-specific effects, and 27 lead SNPs with additive-dominant shared effects. The effects of additive-specific and dominant-specific lead SNPs were shared across breeds to a certain degree. By integrating expression quantitative trait loci, we identified 40 potential dominant-effect and 10 potential additive-effect regulatory circuits, in which a genetic variant affects uterine capacity by modulating the expression of specific gene in specific tissue. For example, rs343882381 affects uterine capacity by regulating the expression of <em>SLC38A10</em> in the uterus via a dominant effect (<em>P</em>_SMR = 7.34 × 10⁻⁵, COLOC.PP4 &gt; 0.5), rs337112076 affects uterine capacity by regulating the expression of <em>TNNT1</em> in the brain via an additive effect (<em>P</em>_SMR = 2.36 × 10⁻³⁵, COLOC.PP4 &gt; 0.5). Our results not only fill the knowledge gap regarding dominant genetic regulation mechanisms of uterine capacity but also provide a key theoretical foundation for the subsequent functional validation and breeding applications.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 8","pages":"Article 101599"},"PeriodicalIF":4.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144771410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 replacing alfalfa hay with wheat silage on growth performance, nutrient digestibility, ruminal fermentation, and serum metabolites in feedlotting lambs","authors":"H. Chen ,&nbsp;Y. Jiang ,&nbsp;W. Li ,&nbsp;Z. Cui ,&nbsp;Z. Cao ,&nbsp;H. Yang","doi":"10.1016/j.animal.2025.101500","DOIUrl":"10.1016/j.animal.2025.101500","url":null,"abstract":"<div><div>This study investigated the potential of using wheat silage (<strong>WS</strong>) as a partial or complete replacement for alfalfa hay (<strong>AH</strong>) in the diets of feedlotting lambs, addressing the global challenge of high feed costs and forage scarcity in livestock production. Wheat silage is widely cultivated across many regions, making it a practical and cost-effective alternative to alfalfa hay, particularly in areas where alfalfa is expensive or scarce. Sixty-four male small-tailed Chinese Han lambs with similar BWs (15.6 ± 0.41 kg) were selected and divided into four treatment diets according to the proportion of wheat silage replacing alfalfa hay:WS0 (WS: AH = 0: 100), WS36 (WS: AH = 36: 64), WS64 (WS: AH = 64: 36), and WS100 (WS: AH = 100: 0). Forage to concentrate ratios were fixed at (25:75) during Stage 1 (lambs aged 2–4 months) and (20:80) during Stage 2 (lambs aged 4–6 months). Results demonstrated that the digestibilities of ADF and NDF were greater (<em>P</em> &lt; 0.01) in both WS36 and WS64 than in the WS100 group during Stage 1, and no significant differences were observed between the WS0 and WS100 groups. However, during Stage 2, the digestibility of both ADF and NDF was significantly lower in the WS100 group compared to the other three treatments. In terms of growth performance, the WS36 group had the greatest final BW in both stages. Ruminal pH and the molar propionate percentage decreased linearly with the increase of WS inclusion, while the molar acetate percentage and acetate: propionate ratio increased linearly with the increase of WS inclusion in both stages. However, the concentration of ammonia nitrogen, microbial CP, and total volatile fatty acids in the rumen showed a significant linear decrease in Stage 2. Among serum metabolism indexes, the insulin-like growth factor-1 decreased linearly (<em>P</em> &lt; 0.01), while creatinine increased linearly with the increasing WS inclusion (<em>P</em> &lt; 0.01). Meanwhile, serum total protein tends to decrease linearly in Stage 2 (<em>P</em> &lt; 0.01). These findings highlight the international relevance of wheat silage as a sustainable forage alternative in intensive livestock systems worldwide. In summary, feeding a total mixed ration containing 36% wheat silage instead of alfalfa hay improved growth performance and nutrient digestibility, offering a viable solution for sustainable lamb production globally.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 8","pages":"Article 101500"},"PeriodicalIF":4.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review: A journey into the black soldier fly digestive system: From current knowledge to applied perspectives","authors":"D. Bruno ,&nbsp;M. Casartelli ,&nbsp;J. De Smet ,&nbsp;M. Gold ,&nbsp;G. Tettamanti","doi":"10.1016/j.animal.2025.101483","DOIUrl":"10.1016/j.animal.2025.101483","url":null,"abstract":"<div><div>Recent literature on the black soldier fly (<strong>BSF</strong>) confirms the deep interest in this species for the bioconversion of organic waste, including challenging substrates that contain recalcitrant macromolecules, and highlights the growing trend in new applications for this insect. While protein meal remains the most prominent use of BSF larvae, emerging research is increasingly exploring alternative applications of biomolecules derived from these larvae, including proteins, lipids, chitin, and antimicrobial peptides. Moreover, the high feeding versatility of this insect is being recognised in fields beyond animal feed, such as bioremediation, where its potential ability to degrade contaminants can present significant ecological benefits. Although there is now widespread agreement that a thorough understanding of BSF biology is essential to enlarge the range of applications in which this insect may offer new sustainable solutions, studies on the digestive system are still limited and we are far from having a whole comprehension of the functional features of this complex structure. In fact, the gut is not only the core of the bioconversion process but also represents the first defence barrier against ingested pathogens, and due to the presence of a highly versatile gut microbiota, it may be a potential source of novel microbes and enzymes that could find application in various biotechnological sectors. This review aims to provide a comprehensive overview of the current knowledge on the BSF midgut −the central region of the gut responsible for nutrient digestion and absorption- in both larvae and adults, together with information about mouthparts and the organisation of the alimentary canal. Moreover, starting from the most recent studies on the midgut and its microbiota, we discuss implications for improving larval production, exploiting challenging substrates, and mitigating pollutants in contaminated biomasses.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 ","pages":"Article 101483"},"PeriodicalIF":4.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144025460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Steering protein fermentation by adding fibres in pig diets","authors":"L. Noorman ,&nbsp;A.F. Bekebrede ,&nbsp;S. de Vries ,&nbsp;A.K. Kies ,&nbsp;W.J.J. Gerrits","doi":"10.1016/j.animal.2025.101615","DOIUrl":"10.1016/j.animal.2025.101615","url":null,"abstract":"<div><div>Protein fermentation is associated with diarrhoea in pigs through the presence of potentially toxic metabolites, including ammonia, branched−chain fatty acids, biogenic amines, and indolic and phenolic compounds. One approach to reduce these metabolites is the dietary inclusion of fibres. In this experiment, 128 boars (mean BW ± SEM; 24 ± 1.5 kg) were assigned to diets without added fermentable fibres (<strong>NFF</strong>), with rapidly fermentable fibres (<strong>RFF</strong>), or with slowly fermentable fibres (<strong>SFF</strong>), using either bovine collagen (<strong>BC</strong>) or zein (<strong>ZE</strong>) as the only, low-digestible protein source. In addition, two control groups received easily digestible whey protein isolate (<strong>WPI</strong>) either with NFF or SFF. After 2 weeks, digesta contents from the ileum, cecum, proximal- and distal colon were analysed to assess protein digestibility, digesta mean retention time, and the concentrations and flows of protein-derived metabolites. Metabolite flow was used as a proxy for the extent of protein fermentation, reflecting the net appearance of metabolites, while the concentrations provided insight into the direct exposure of the intestinal epithelium to these metabolites. Metabolite flow was generally linked to the precursor amino acid profiles of the protein sources. Apparent ileal protein digestibility did not differ significantly between BC and ZE, except when RFF were added (Fibre × Protein &lt; 0.05), where it was lower in ZE-fed pigs (<em>P</em> &lt; 0.05). Both fibre treatments, but particularly SFF, reduced the concentrations of most protein-derived metabolites. The effects of RFF and SFF on colonic metabolite flows varied depending on metabolite type and protein source. In the proximal colon of ZE-fed pigs, dietary fibres reduced the flows of branched−chain fatty acids (<strong>BCFA</strong>; RFF: 26%, SFF: 33%), indole (RFF: 70%, SFF: 59%), and p-cresol (SFF: 28%), while no effects were observed in BC-fed pigs (Fibre × Protein &lt; 0.05). No fibre effects on the flows of ammonia, biogenic amines, valeric acid, phenol, and skatole were observed in either BC- or ZE-fed pigs. In WPI-fed pigs, SFF significantly increased the flows of BCFA (47%), p-cresol (75%), and biogenic amines (120%; all <em>P</em> &lt; 0.05) in the proximal colon. It can be concluded that protein fermentation primarily occurs in the proximal colon, starting in the ileum, with metabolite production generally linked to amino acid precursor composition. While dietary fibres reduced the concentrations of most protein-derived metabolites, the ability of different fibres to steer the extent of protein fermentation is strongly dependent on the source of proteins being fermented.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 9","pages":"Article 101615"},"PeriodicalIF":4.2,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144890925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Health and performance of fattening pigs reared in grassland and agroforestry systems in a temperate maritime climate","authors":"S. Buijs ,&nbsp;C. McFarland ,&nbsp;R. Olave ,&nbsp;R. Muns","doi":"10.1016/j.animal.2025.101616","DOIUrl":"10.1016/j.animal.2025.101616","url":null,"abstract":"<div><div>Outdoor pig production is often seen as more welfare-friendly than indoor production. However, unless restricted to concrete runs, it is often carried out on grassland. This offers little protection from adverse climatic conditions and grassland is susceptible to poaching during rainy periods. Both can be expected to negatively impact pig health, whereas the use of wooded areas can limit such issues as trees provide shelter and promote water evaporation. To investigate this, we compared the health of pigs kept in grassland and agroforestry plots from 8 weeks of age until slaughter. Two batches of pigs were used, which were kept in groups of six boars, with four groups per treatment for each batch. As expected, sunburn was significantly less common for the agroforestry treatment than for the grassland treatment, although severe sunburn was absent overall. Growth and feed disappearance were significantly greater in the agroforestry treatment, without affecting feed conversion, body condition score or faecal consistency. The treatments had a statistically significant but limited effect on some other measured variables. Ear damage and body lesions were somewhat more frequent in the agroforestry treatment than in the grassland treatment (significantly so for the body lesions and tending towards significance for ear damage). Furthermore, gait scores were slightly but significantly worse in the agroforestry treatment than in the grassland treatment for most of the experiment, although the opposite relation was found during the last weeks. Gait scores may have reflected terrain conditions more than leg health, as no difference between the treatments was found when pigs were later re-scored when on concrete. Several of the expected health issues were either completely or nearly absent, including tail damage (even though tails were undocked), swellings, ecto- and endoparasites, melena, hematochezia, nasal discharge and reduced cleanliness. In conclusion, we found that the agroforestry treatment protected fattening pigs from sunburn and increased their growth, whilst some other health aspects were affected negatively but only to a marginal extent. Overall, health status was good for both treatments, likely in part due to the use of pigs and plots that had no history of pathogen build-up, and the fact that all pigs had access to rootable soil preventing a redirection of damaging behaviour to other pigs.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 9","pages":"Article 101616"},"PeriodicalIF":4.2,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144879556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review: Effect of breeding strategies, feeding and manure management, to mitigate methane emissions in dairy cattle farming: an overview and the road ahead","authors":"T. Zanon ,&nbsp;C. Baes ,&nbsp;F. Miglior ,&nbsp;M. Gierus ,&nbsp;M. Gauly","doi":"10.1016/j.animal.2025.101617","DOIUrl":"10.1016/j.animal.2025.101617","url":null,"abstract":"<div><div>Ruminant production systems, in particular those involving cattle, play a substantial role in greenhouse gas emissions, particularly because of the amount of methane (<strong>CH₄</strong>) that they eruct. Here, we describe and incorporate the most relevant interdisciplinary approaches to mitigating CH₄ emissions in dairy cattle farming. We examine genetic selection for reduced daily CH₄ production, including key methods (direct measurement and mid-infrared spectroscopy predictions) now being integrated into breeding goals in some countries (e.g., Canada). We also evaluate feeding interventions, such as forage digestibility improvements and the use of additives (tannins, algae, and specialised compounds like 3-nitrooxypropanol), which may reduce CH₄ production in the rumen. Finally, we discuss manure management strategies (anaerobic digestion, reduced storage time, lower temperature) that can mitigate CH₄ release. By combining these approaches, producers can potentially reduce CH₄ emissions per unit of milk while maintaining productivity. However, important challenges persist — such as scaling up breeding practices without simply shifting emissions to beef systems, and verifying long-term impacts of dietary additives. We conclude that integrated breeding, feeding, and manure management strategies, supported by robust research and policy incentives, are essential for curbing dairy CH₄ emissions while ensuring sustainable milk production worldwide.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 9","pages":"Article 101617"},"PeriodicalIF":4.2,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144908387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Are olfactory stimuli able to induce emotional responses in a positive context in ewes?","authors":"I. Achin ,&nbsp;C. Parias ,&nbsp;M. Morisse ,&nbsp;B. Mulot ,&nbsp;G. Lefort ,&nbsp;S.A. Love ,&nbsp;E. Chaillou","doi":"10.1016/j.animal.2025.101611","DOIUrl":"10.1016/j.animal.2025.101611","url":null,"abstract":"<div><div>The perception of olfactory stimuli can influence animal emotions and behaviours, which are critical for survival and adaptation. This study explored the properties of three olfactory stimuli (orange essential oil, wolf faeces, and cadaverine) to induce emotion in sheep, in a non-stressful environment enriched with social and food resources. Contrary to expectations, wolf faeces, while repellent, did not trigger overt stress behaviours such as increased vocalisations or agitation. Similarly, orange essential oil did not elicit strong positive valence responses, suggesting that the positive experimental context may mask its effect. Interestingly, cadaverine, typically associated with body decomposition, has no impact on sheep behaviours except that is induced emetic responses in two individuals, indicating potential disgust. Overall, this research highlights the complex interplay between social, food, and environmental factors in shaping the emotional responses of sheep to olfactory stimuli, underscoring the importance of context and individual variability. These findings contribute to a better understanding of olfactory influences on animal welfare and behaviour.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 10","pages":"Article 101611"},"PeriodicalIF":4.2,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145021102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the impact of heat stress on feed efficiency in tropical beef cattle using genomic reaction norm models","authors":"J.B. Silva Neto ,&nbsp;L.F. Brito ,&nbsp;L.F.M. Mota ,&nbsp;M.R.G. Silva ,&nbsp;G.R.D. Rodrigues ,&nbsp;F. Baldi","doi":"10.1016/j.animal.2025.101612","DOIUrl":"10.1016/j.animal.2025.101612","url":null,"abstract":"<div><div>Global climate change poses significant challenges to livestock production, particularly in tropical regions where cattle frequently experience heat stress (<strong>HS</strong>). HS negatively impacts feed efficiency by reducing feed intake, altering metabolic processes, and increasing energy requirements, leading to decreased animal performance. Understanding how cattle respond to environmental stressors is essential for improving efficiency by breeding programs. In this context, we investigated genotype-by-environment interaction (<strong>G × E</strong>) for dry matter intake (<strong>DMI</strong>) and residual feed intake (<strong>RFI</strong>) in Nellore cattle using bi-trait genomic reaction norm models and considering the temperature-humidity index (<strong>THI</strong>) as the environmental descriptor. Data from 22 838 animals collected between 2011 and 2023 across 21 Brazilian farms were analyzed. Meteorological data were obtained via NASA POWER, and THI values were calculated based on the average temperatures and relative humidity recorded during feed efficiency trials. Genomic data were available for 18 567 animals, and the genetic parameters were estimated using the single-step genomic best linear unbiased prediction approach. The genetic expression of feed efficiency traits was found to be influenced by climatic conditions, with heritability estimates for DMI (ranging from 0.22 to 0.39) and RFI (ranging from 0.08 to 0.28) varying across the THI gradient. Additionally, a reduction in additive genetic variance for both traits was observed under intense heat stress conditions, suggesting the important role of environmental factors on phenotypic variability of feed efficiency traits in Nellore cattle. The presence of G × E was more pronounced when THI exceeded 76, as genetic correlations for the same trait across different environmental gradients dropped below 0.80, leading to substantial sire reranking. Moreover, the genetic relationship between DMI and RFI also varied along the THI, with genetic correlations ranging from 0.64 to 0.72, highlighting alterations in the genetic expression of feed efficiency traits under different heat stress levels. These findings emphasize the need to consider genetic plasticity when selecting animals for improved feed efficiency in tropical regions. Overall, this study provides valuable insights for breeding programs aimed at improving beef cattle resilience to heat stress, ensuring sustainable production in the face of climate change.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 9","pages":"Article 101612"},"PeriodicalIF":4.2,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144842247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}