Animal最新文献

{"title":"Biogenic and fossil main greenhouse gas emissions of dairy, beef, pig and poultry systems","authors":"M. Berton,&nbsp;E. Sturaro,&nbsp;S. Schiavon,&nbsp;G. Bittante,&nbsp;A. Cecchinato,&nbsp;G. Xiccato,&nbsp;L. Gallo","doi":"10.1016/j.animal.2025.101562","DOIUrl":"10.1016/j.animal.2025.101562","url":null,"abstract":"<div><div>Conventional analyses of the carbon footprint of livestock systems do not consider the relationships between the characteristics and sources of each greenhouse gas (<strong>GHGs</strong>; CH₄, N₂O, CO₂) and the different livestock systems. This study aimed to assess the carbon footprint of a variety of livestock systems, including different animal categories (dairy cattle, beef cattle, pig and poultry) and production circumstances (lowland and mountain areas). An attributional cradle-to-gate-of-the-farm Life Cycle Assessment was used, considering the emission pattern of each GHG and distinguishing fossil and biogenic origins. The production stages included animal and manure management, on– and off-farm feed production and the production and use of the farm materials. The functional unit was 1 kg of crude protein in animal food (<strong>CPAF</strong>). Emissions per single GHG and production stage were analysed with a general linear model which included the effect of the livestock system, which proved to significantly influence the emission pattern of all GHGs, both in absolute terms (kg/kg CPAF) and with respect to the single production stage. The CO₂ (fossil-based) resulted as the most emitted GHG (10.2–27.6 kg/kg CPAF), 10–255 and 284–646 times greater than CH₄ and N₂O, respectively. Methane was found to be more associated with the animal category (ruminants), whereas N₂O and CO₂ were more associated with the input intensity level. Livestock systems strongly influenced the biogenic GHG emissions but not the fossil-related one, with dairy, pig and poultry systems showing similar and lower values than beef. In conclusion, the evaluation of the pattern of each GHG as well as of their biogenic or fossil origin can give indications to address the reduction of global warming.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 7","pages":"Article 101562"},"PeriodicalIF":4.0,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144329686","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":"Effects of algal supplementation on broiler chicken growth performance, gut development, blood leukocyte counts and antibody levels","authors":"E. Ivarsson ,&nbsp;H. Wall ,&nbsp;A. Wistedt ,&nbsp;G. Cervin ,&nbsp;H. Pavia ,&nbsp;E. Wattrang","doi":"10.1016/j.animal.2025.101560","DOIUrl":"10.1016/j.animal.2025.101560","url":null,"abstract":"<div><div>Brown macroalgae contains complex polysaccharides including laminarins that have shown prebiotic potential. The aim of this study was to investigate if feeding algal products from <em>Saccharina latissima</em> to either broiler breeders or directly to their chickens could affect growth performance, gut- and immune development in the chickens. A total of 45 hens of the parent line of Ross 308 were used to obtain fertilised eggs. The hens were fed one of three experimental diets, a control, the addition of 0.6% algal meal or addition of 0.08% algal extract. The progenies of those hens were followed in an experiment using a split-plot design where eggs from the three hen treatments were distributed into 24 modules. Half of the modules were assigned a control diet, and half of the modules were a diet supplemented with 725 ppm algal extract. A total of 255 chicks remained after hatching and individual marking, they were weighed at hatch, on days 3, 7, 14, and 37 and blood samples for determination of leukocyte counts and serum antibody levels were drawn on days 3, 7 and 12. Chickens were killed to assess organ development at days 7, 14 and 37, and histological examination of ileal tissue was performed on day 7. The results showed that chicks fed the algal extract diet had higher (<em>P</em> &lt; 0.05) BW on days 3, 7 and 37, a higher proportion of serum immunoglobulin Y (<strong>IgY</strong>) and a lower proportion of maternal antibodies to infectious bronchitis virus on day 12 (<em>P</em> &lt; 0.05). Chicks fed algal extract showed higher numbers (<em>P</em> &lt; 0.05) of CD4+CD8- helper T-cells and total T-cell receptor (<strong>TCR</strong>)γ/δ+ T-cells, and among the TCRγ/δ+ T-cell subpopulations, the TCRγ/δ+CD8- T-cells were increased, and lower (<em>P</em> &lt; 0.05) numbers of cluster of differentiation (<strong>CD</strong>)4+CD8αα+ and TCRγ/δ+CD8αβ+ T-cells in the circulation. Feeding algal extract to the breeders resulted in higher chick BW on day 7, and the villus height−to−crypt depth ratio was higher (<em>P</em> &lt; 0.05) for chicks from hens fed algal extract than for chicks from hens fed algal meal. In conclusion, feeding algal extract from <em>Saccharina latissima</em> directly to the chicken improved growth performance throughout the growing period and altered the composition of T-cell populations in the circulation and may have enhanced the chicks’ IgY production. Maternal supplementation of algal extract to breeder hens had positive effects on the chickens’ early growth performance and gut architecture. However, no synergistic effects of both maternal feeding and direct supplementation to the chicken were found.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 7","pages":"Article 101560"},"PeriodicalIF":4.0,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322691","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":"Feeding on the move: assessing the effect of feeding during long-distance ferry transport on the physiology, clinical signs of disease and activity of unweaned calves","authors":"L.L. van Dijk ,&nbsp;S. Siegmann ,&nbsp;P. Bennett ,&nbsp;K. Sugrue ,&nbsp;C.G. van Reenen ,&nbsp;E.A.M. Bokkers ,&nbsp;G. Sayers ,&nbsp;M. Conneely ,&nbsp;N.L. Field","doi":"10.1016/j.animal.2025.101561","DOIUrl":"10.1016/j.animal.2025.101561","url":null,"abstract":"<div><div>Long-distance transport of unweaned calves and associated fasting can negatively impact their physiology, and practical strategies to mitigate extended fasting times have not been studied previously. This study aimed to assess changes in the physiology, clinical signs of disease, and activity of unweaned calves as a result of providing access to feed (milk replacer) on board a trailer during a road/ferry/road journey from Ireland to The Netherlands. Calves were transported from an assembly centre (Ireland), via lairage (France), to a veal farm (The Netherlands). Calves were provided milk replacer on-board the trailer during the ferry section of the transport using an on-board feeding system (<strong>FEED</strong>; n = 40), or included as controls (<strong>CONT</strong>; n = 60). Calves were blood sampled and weighed, and clinical signs of disease were scored prior to departure from Ireland (Day 0), upon arrival at the lairage (Day 1), upon arrival at the veal farm (Day 2), and 1−week postarrival (Day 9). A subset of calves were equipped with activity sensors and continuous glucose monitors (<strong>CGM</strong>). Most blood variables differed between FEED and CONT calves on Day 1; glucose was higher (4.8 vs 4.0 mmol/L) and beta-hydroxybutyrate (0.20 vs 0.34 mmol/L), non-esterified fatty acids (0.52 vs 0.71 mmol/L), and lactate (0.85 vs 1.25 mmol/L) were lower for FEED compared to CONT calves; no blood variables showed significant differences at the next timepoint (all <em>P</em> &gt; 0.05). Clinical signs of disease and BW did not reveal significant differences between treatment groups during transport. Step count was higher for FEED than for CONT calves at the time of feeding on the ferry (172 vs 37 steps/h), but not at any other time. CGM glucose was higher for FEED calves at 21 h (5.9 vs 4.9 mmol/L) and 22 h (6.0 vs 4.9 mmol/L), but lower for FEED calves at 27 h (7.4 vs 9.3 mmol/L), 28 h (7.9 vs 9.1 mmol/L), and 30 h (7.3 vs 8.3 mmol/L). In general, blood variables showed a shift towards normal ranges after on-board feeding; however, these effects diminished following a second prolonged fasting period after lairage in France. Differences in clinical signs of disease, weights, activity, and CGM were inconsistent across time points. On-board provision of milk replacer is currently challenging but has the potential to improve the physiological status of calves. Systems need to be developed further, and more research is needed to perfect the on-board feeding of calves during transport.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 7","pages":"Article 101561"},"PeriodicalIF":4.0,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338886","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":"Influences on calf productivity during five decades of cow-calf grazing of northern prairie","authors":"J.G.N. Irisarri ,&nbsp;P.A. Cipriotti ,&nbsp;L. Castro Sardiña ,&nbsp;M. Mortenson ,&nbsp;Justin D. Derner","doi":"10.1016/j.animal.2025.101557","DOIUrl":"10.1016/j.animal.2025.101557","url":null,"abstract":"<div><div>Understanding calf weight gains from grazing rangeland ecosystems requires long-term data to disentangle influences of biophysical and animal factors, and management. However, long-term experiments with consistent management treatments with livestock weight gain data are scarce. To address this gap, we analyzed a legacy dataset of grazing during the growing season (June-September) in native northern mixed-grass prairie of the North American Great Plains that included individual on– and off-pasture weights of Hereford (1975–2001) and crossbreed (2003–2021) cows and calves grazing from June to September, spanning 47 years near Cheyenne, Wyoming. We used regression tree analyses to evaluate the influences of biophysical (forage production estimated via NDVI LANDSAT time series, temperature, and precipitation) and individual animal factors (breed (Hereford from 1975 to 2001 and crossbred from 2003 to 2021), cow age, cow BW, and calf gender), and management (stocking rate, Animal Unit Days per hectare), on individual calf weight gain. We observed a positive temperature trend and a negative precipitation trend over the five decades. Forage production was positively associated with precipitation and negatively with temperature. Breed (Hereford vs crossbred) was the most important factor for calf weight gain, followed by stocking rate, temperature, cow weight, precipitation, cow age, forage production and calf gender, with the fitted model explaining 64% of the variation in calf weight gain. Calves from crossbred cows gained 26% more than calves from Hereford cows (1.2 vs 0.88 kg/head per day). Our findings from nearly five decades of grazing research offer key insights for beef production responses from native, northern mixed-grass prairie rangeland ecosystems. First, crossbreeding offers advantages to calf weight gain. Second, the importance of stocking rate and cow BW on calf weight gain, along with observed trends of precipitation and temperature influencing forage production, underscores the need for more flexible management for sustainable beef production. Third, over the five decades of this experiment, factors influencing individual productivity have shifted from variables associated with the selection of the animal biotype and stocking rate to primarily climatic factors. The shift from management-driven factors to more variable climate-driven influences reflects the need for adaptive grazing management —a structured approach that involves planning, monitoring, and adjusting strategies in response to environmental variability.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 7","pages":"Article 101557"},"PeriodicalIF":4.0,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144313642","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":"Productive performance of yellow mealworm larvae in different protein and carbohydrate levels in the same energy substrate","authors":"G.X. Huang ,&nbsp;Y.R. Zhang ,&nbsp;T.H. Yu,&nbsp;B.Q. Yuan,&nbsp;D.W. Huang,&nbsp;J.H. Xiao","doi":"10.1016/j.animal.2025.101555","DOIUrl":"10.1016/j.animal.2025.101555","url":null,"abstract":"<div><div>Yellow mealworm (<em>Tenebrio molitor</em>) larvae can efficiently convert waste into high-quality insect protein. However, the specific nutritional requirements of <em>Tenebrio molitor</em> larvae remain largely unclear. Therefore, this study aimed to investigate the optimal substrate composition in terms of protein and carbohydrate content for rearing <em>Tenebrio molitor</em> larvae for food and feed applications. Five isoenergetic and isolipid substrates were formulated, with protein content ranging from 10 to 30%, carbohydrate content ranging from 29.72 to 68.15%, and a protein-to-carbohydrate ratio varying from 1:1 to 1:7. Three replicates of larvae (approximately 10 mm in length, 15 g per replicate, approximately 1 297 larvae per box) were fed each substrate for 8 weeks under controlled conditions in a constant-temperature incubator and subsequently harvested. The results demonstrated that larvae fed on a substrate containing 15% protein (corresponding to 58.34% carbohydrate content) and a protein-to-energy ratio of 10.19 g/MJ achieved the highest final yield, the most efficient food conversion, and the greatest substrate protein conversion efficiency. Additionally, feeding substrates with higher protein content negatively impacted larval growth. In summary, this study concluded that to achieve high yields while ensuring optimal utilisation of substrate resources and minimising feeding costs, it is recommended to use a substrate with 15% protein content, a protein-to-carbohydrate ratio of 1:5, and a protein−to−energy ratio of 6.82 g/MJ.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 7","pages":"Article 101555"},"PeriodicalIF":4.0,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322611","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":"Gestating sows exhibit greater ileal amino acid digestibility of corn distillers grains, rapeseed meal, and cottonseed meal than growing pigs, but not soybean meal","authors":"B. Lei ,&nbsp;G. Lv ,&nbsp;X. Mo ,&nbsp;L. Hua ,&nbsp;X. Jiang ,&nbsp;B. Feng ,&nbsp;L. Che ,&nbsp;S. Xu ,&nbsp;Y. Lin ,&nbsp;F. Wu ,&nbsp;D. Wu ,&nbsp;Y. Zhuo","doi":"10.1016/j.animal.2025.101556","DOIUrl":"10.1016/j.animal.2025.101556","url":null,"abstract":"<div><div>Precise measurement of ileal amino acid digestibility in feed ingredients is vital for optimising sows’ nutrient requirements and feed utilisation. We hypothesised that the ileal amino acid digestibility of feed ingredients for swine, which usually are determined in growing pigs, may not accurately reflect their actual digestibility in gestating sows. This experiment aimed to compare the apparent and standardised ileal CP and amino acid (<strong>AA</strong>) digestibility of four protein-feed ingredients, including soybean meal, corn distiller’ dried grains with solubles (<strong>DDGS</strong>), rapeseed meal (<strong>RSM</strong>), and cottonseed meal (<strong>CSM</strong>), between gestating sows and growing pigs. These feed ingredients were used as the sole sources of CP and AA to formulate four experimental diets for both gestating sows and growing pigs. Two nitrogen-free diets were formulated to estimate the endogenous AA losses for gestating sows and growing pigs, respectively. Ten barrows, with an average weight of 35.0 ± 1.6 kg, were randomly assigned to five treatments in a replicated 5 × 4 incomplete Latin square design (five diets and four periods) with eight replicates. For the sow trial, ten gestating sows, with an average weight of 238.9 ± 9.3 kg, were randomly assigned to five diets in a replicated 5 × 3 incomplete Latin square design (five diets and three periods) with six replicates. Each diet was fed for 7 days: 5 days for adaptation, with ileal digesta collected after the first meal on days six and seven. There were no differences between growing pigs and gestating sows for the standardised ileal digestibility (<strong>SID</strong>) of CP and AA from soybean meal. However, gestating sows had greater SID for isoleucine, leucine, phenylalanine, valine, alanine, cysteine, and glutamic acid from DDGS compared with growing pigs (<em>P</em> &lt; 0.05). In addition, gestating sows had greater SID for CP and AA from RSM, except for lysine, tryptophan, cysteine, and glycine, compared with growing pigs. Gestating sows also had greater SID of leucine (<em>P</em> = 0.02) when fed the CSM diet compared with growing pigs. The reduced SID of CP and AA in growing pigs fed the DDGS, RSM, and CSM diet was associated with decreased activities of trypsin and chymotrypsin in the ileal digesta. In conclusion, gestating sows had greater ileal AA digestibility for non-conventional feed ingredients such as DDGS, RSM, and CSM, which stresses the importance of a separate feed ingredient value for sows.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 7","pages":"Article 101556"},"PeriodicalIF":4.0,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322690","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: Keystone issues in ruminant science I. Feed intake control in ruminants.","authors":"W Pittroff, M M Kothmann","doi":"10.1016/j.animal.2025.101553","DOIUrl":"10.1016/j.animal.2025.101553","url":null,"abstract":"<p><p>In 1999, we were invited to review the literature on feed intake control in ruminants for the V^th International Symposium on the Nutrition of Herbivores (Pittroff and Kothmann, 1999). Our key findings were: (1) the dominating bi-phasic intake control model, with physical intake control at low DM digestibilities changing to metabolic control at higher DM digestibilities, is not supported by experimental evidence; (2) although main substrates in energy metabolism differ between ruminants and monogastrics, principal intake control mechanisms appear to be the same; (3) the most likely central intake control element is ATP generation in the liver; (4) peripheral anabolic and catabolic processes, which change fuel supply to the liver, produce predictable adjustments in feed intake: (5) tissue-available N for synthesis plays a pivotal role in the dynamics of nutrient allocation and therefore in fuel storage, and fuel oxidation in the liver and periphery. From these findings, it follows that multiple interactions between feed components, and between feed components and animal characteristics determine feed quality in the ruminant. Consequently, static factorial feed requirement systems cannot optimise the match between feed supply and animal requirements. We were asked again to review the literature on feed intake control for the 11th ISNH and conclude, 25 years later, that important new experimental evidence supports our original conclusions and hypotheses. However, although key elements of our new theoretical concept were taken up by other authors (albeit unreferenced), corresponding new developments in feed requirement prediction models did not occur and consequently, major progress in optimising feed resource utilisation in ruminant production is absent. We discuss the reasons and future research directions, including a brief critical review of 'big data' proposals for the optimisation of ruminant nutritional management.</p>","PeriodicalId":50789,"journal":{"name":"Animal","volume":" ","pages":"101553"},"PeriodicalIF":4.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337193","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: Keystone issues in ruminant science II. Environmental impact of ruminants: methane emissions and rangeland degradation.","authors":"M M Kothmann, W Pittroff","doi":"10.1016/j.animal.2025.101554","DOIUrl":"https://doi.org/10.1016/j.animal.2025.101554","url":null,"abstract":"<p><p>Since the publication of the UN-FAO report on the environmental impact of livestock production in 2006, negative headlines seem to rule the public perception of ruminant livestock production. Two themes dominate this discussion: the emission of greenhouse gases, and the worldwide degradation of grazing resources. We show that currently used methods for source strength estimation in global methane budget models cannot produce independent estimates and therefore do not qualify as support of policy decisions. We further submit that there is no justification for the view that methane output by ruminants is a key priority area of research in ruminant nutrition. We review the history of methodology and application of vegetation monitoring on rangelands and its interaction with grazing management. We discuss some of the reasons why rangeland conservation management has become globally so divergent in its application scope and success, with widespread resource degradation observed worldwide. This is a critically relevant topic affecting a natural space occupying more than half of the global landmass, and constituting the most important feed resource for global livestock production. Achieving sustainable management of rangelands has been a challenge around the world throughout recorded history. The integrated management of grazing and prescribed fire as the keystone practices should be based on sound ecological principles and be supported by management-oriented decision-support tools. This has not been accomplished yet. In the past couple of centuries, historic grazing and fire regimes have been significantly disrupted worldwide, often in conjunction with excessive grazing, causing widespread rangeland degradation. These problems are linked to increasing human and livestock populations and changing cultures. Increasing human populations are also the key factor in the ever-expanding conversion of historic rangelands into rainfed crop production areas. These occur on semi-arid lands not allowing long-term sustainable use for crop production and consequently, they lead to extremely detrimental consequences for the environment and for the climate. With this paper, we introduce key concepts in rangeland monitoring to animal scientists in order to facilitate a deeper understanding of the current problems in conservation management of one of the most important resources for livestock production. We explore the problem of rangeland degradation related to livestock grazing and the role of rangeland management in providing solutions. We discuss how rangeland and animal management must be integrated to ensure long-term use of this resource, without which global livestock production would not be feasible.</p>","PeriodicalId":50789,"journal":{"name":"Animal","volume":" ","pages":"101554"},"PeriodicalIF":4.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144486839","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":"Corrigendum to “Does the diurnal pattern of enteric methane emissions from dairy cows change over time?” [Animal 12(10) (2018) 2065–2070]","authors":"M.J. Bell,&nbsp;J. Craigon,&nbsp;N. Saunders,&nbsp;JR Goodman,&nbsp;P.C. Garnsworthy","doi":"10.1016/j.animal.2025.101492","DOIUrl":"10.1016/j.animal.2025.101492","url":null,"abstract":"","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 6","pages":"Article 101492"},"PeriodicalIF":4.0,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144131054","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":"The candidate gene OLFML2A possibly contributed to the variation of total number of teats in Meishan and Erhualian pigs by influencing the formation of mammary placodes","authors":"C.X. Liu ,&nbsp;R.H. Huang ,&nbsp;W.D. Zhou ,&nbsp;N.J. Jiang ,&nbsp;Q. Liu ,&nbsp;J.F. Ma ,&nbsp;P.H. Li ,&nbsp;Q.B. Zhao","doi":"10.1016/j.animal.2025.101552","DOIUrl":"10.1016/j.animal.2025.101552","url":null,"abstract":"<div><div>The teat number trait in pigs has significant economic value, with Meishan and Erhualian pigs having the highest counts globally. To uncover the genetic basis of teat number variation, this study employed genome re-sequencing for a total of 1 119 individuals. Genome-wide association study (<strong>GWAS</strong>), meta-analysis, and Bayesian fine mapping were conducted. The GWAS from two breeds revealed multiple significant quantitative trait locus (<strong>QTL</strong>) for total teat number (<strong>TNT</strong>) mainly on SSC1, SSC5, SSC10, and others. Bayesian fine mapping targeted the most significant QTL in both Meishan pig GWAS and meta-analysis, mapping it to SSC1: 264 609 542 – 266 079 236 bp. Within this QTL, eighteen protein-coding genes were annotated. Bayesian fine mapping was performed for the second most significant QTL in meta-analysis, which also was the most significant QTL in Erhualian pig GWAS, identifying its mapping at SSC5: 58 228 193 − 59 198 414 bp. One protein-coding gene was annotated within this QTL. After determining the anatomical location of the mammary placodes, RNA-seq results from mammary placodes of extremely high and low 26-day-old Erhualian pig embryos were integrated, and found that only <em>OLFML2A</em> showed significant differential expression among these nineteen candidate genes. <em>OLFML2A</em> was primarily enriched in the extracellular matrix and extracellular matrix organisation pathways, which may play a role in the interaction between epithelial and stromal cells in mammary placodes. In addition, the utilisation of PigGTEx data for transcriptome-wide association study revealed a significant association between the expression level of <em>OLFML2A</em> in the placenta and TNT in Meishan pig. The results of phenome-wide association study further validate the significant association of <em>OLFML2A</em> with teat number traits in lean-type commercial pigs. Molecular validation experiments confirmed that <em>OLFML2A</em> specifically expresses mRNA and protein in mammary placodes. Reverse transcription-quantitative PCR results further confirmed significant differences in gene expression in the mammary placodes between extremely high and low 26-day-old Erhualian pig embryos, with the high group showing significantly higher expression levels. Differential expression analysis of mammary placodes from different litters further confirmed that the differential expression of <em>OLFML2A</em> was not caused by the litter effect of the sows. After integrating multiple omics, we have tentatively identified the <em>OLFML2A</em> gene as a potential causal gene responsible for teat number variation in Meishan and Erhualian pigs. This gene could potentially influence the development of mammary placodes in Meishan and Erhualian pigs, consequently influencing the phenotype of teat number.</div></div>","PeriodicalId":50789,"journal":{"name":"Animal","volume":"19 7","pages":"Article 101552"},"PeriodicalIF":4.0,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144254908","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}