{"title":"Effects of the temperature-humidity index on conception rates in Holstein heifers and cows receiving in vitro-produced Japanese Black cattle embryos.","authors":"Takamasa Nishisozu, Jaswant Singh, Akinori Abe, Kazuo Okamura, Osamu Dochi","doi":"10.1262/jrd.2022-112","DOIUrl":null,"url":null,"abstract":"<p><p>We investigated the effect of the temperature-humidity index (THI) on the conception rate (CR) in Holstein heifers and cows receiving in vitro-produced (IVP) Japanese Black cattle fresh embryos. IVP embryos were transferred to Holstein heifers (n = 1,407) and cows (n = 3,189) on 245 commercial farms. The monthly average ambient temperature (AT) and THI ranged from 4.7 to 29°C and 41 to 81, respectively; both were the highest in August. The monthly CR ranged from 16.3% to 46.7% in cows and 23.8% to 74.1% in heifers. The CR of heifers was unaffected by THI, AT, or the month of embryo transfer. However, these parameters affected the CR of cows. The CR at THI values of 61-65 and 71-75 was greater than that at THI > 75, whereas other THI values had no effect. The CR at temperatures > 25°C was lower (P = 0.008) than that at temperatures of 15-20°C and 20-25°C. Moreover, the CR was lowest (P = 0.003) in July. THI and parity (P = 0.057 and P = 0.001, respectively) and AT and parity (P = 0.019 and P = 0.001, respectively) showed significant effects on CR; however, there was no interaction between these two factors. In conclusion, AT > 25°C and THI > 75 adversely affect the CR outcome in cows but not in heifers.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":null,"pages":null},"PeriodicalIF":16.4000,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/42/4c/jrd-69-072.PMC10085771.pdf","citationCount":"3","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Accounts of Chemical Research","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1262/jrd.2022-112","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 3
Abstract
We investigated the effect of the temperature-humidity index (THI) on the conception rate (CR) in Holstein heifers and cows receiving in vitro-produced (IVP) Japanese Black cattle fresh embryos. IVP embryos were transferred to Holstein heifers (n = 1,407) and cows (n = 3,189) on 245 commercial farms. The monthly average ambient temperature (AT) and THI ranged from 4.7 to 29°C and 41 to 81, respectively; both were the highest in August. The monthly CR ranged from 16.3% to 46.7% in cows and 23.8% to 74.1% in heifers. The CR of heifers was unaffected by THI, AT, or the month of embryo transfer. However, these parameters affected the CR of cows. The CR at THI values of 61-65 and 71-75 was greater than that at THI > 75, whereas other THI values had no effect. The CR at temperatures > 25°C was lower (P = 0.008) than that at temperatures of 15-20°C and 20-25°C. Moreover, the CR was lowest (P = 0.003) in July. THI and parity (P = 0.057 and P = 0.001, respectively) and AT and parity (P = 0.019 and P = 0.001, respectively) showed significant effects on CR; however, there was no interaction between these two factors. In conclusion, AT > 25°C and THI > 75 adversely affect the CR outcome in cows but not in heifers.
期刊介绍:
Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance.
Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.