{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T23:34:58Z","timestamp":1787009698100,"version":"build-2736575974"},"reference-count":26,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T00:00:00Z","timestamp":1625011200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The objective of this study was to assess differences in reproductive performance of natural service and artificial insemination (AI) sired beef females based on pregnancy outcomes, age at first calving, and calving interval. Data were sourced from 8,938 cows sired by AI bulls and 3,320 cows sired by natural service bulls between 2010 and 2017. All cows were in a commercial Angus herd with 17 management units located throughout Virginia and represented spring and fall calving seasons. All calves were born to dams managed with estrus synchronization. Pregnancy was analyzed with generalized linear mixed models and other reproductive measures with linear mixed models in R. Six models were evaluated with the dependent variables of pregnancy status at the first diagnosis, pregnancy status at the second diagnosis, pregnancy type (AI or natural service) at the first diagnosis, pregnancy type at the second diagnosis, calving interval, and age at first calving. Independent variables differed by model but included sire type of the female (AI or natural service), prebreeding measures of age, weight, and body condition score, postpartum interval, sex of the calf nursing the cow, and management group. No differences were observed between AI- and natural service-sired females based on pregnancy status at first and second pregnancy diagnosis (P &amp;gt; 0.05). Sire type was only found to be significant for age at first calving (P &amp;lt; 0.05) with AI-sired females being 26.6 \u00b1 1.6 d older at their first calving, which was expected because AI-sired females were born early in the calving season making them older at breeding. Surprisingly, age and body condition score were not significant predictors of pregnancy (P &amp;gt; 0.05). Body weight at breeding was not significant for pregnancy (P &amp;gt; 0.05) but was significant for age at first calving (P &amp;lt; 0.05). These data suggested that lighter heifers calved earlier which contradicts our original hypothesis. Overall, commercial Angus females sired by AI or natural service bulls had similar reproductive performance. Factors that were commonly associated with reproductive success were not significant in this commercial Angus herd managed with estrus synchronization. Given the size of these data, the importance of body condition, age, and weight should be reassessed in modern genetics and management practices.<\/jats:p>","DOI":"10.1093\/tas\/txab114","type":"journal-article","created":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T15:10:08Z","timestamp":1625065808000},"source":"Crossref","is-referenced-by-count":7,"title":["Comparison of reproductive performance of AI- and natural service-sired beef females under commercial management"],"prefix":"10.1093","volume":"5","author":[{"given":"Mackenzie A","family":"Marrella","sequence":"first","affiliation":[{"name":"Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robin R","family":"White","sequence":"additional","affiliation":[{"name":"Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicholas W","family":"Dias","sequence":"additional","affiliation":[{"name":"Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claire","family":"Timlin","sequence":"additional","affiliation":[{"name":"Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefania","family":"Pancini","sequence":"additional","affiliation":[{"name":"Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"Currin","sequence":"additional","affiliation":[{"name":"Virginia\u2013Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sherrie","family":"Clark","sequence":"additional","affiliation":[{"name":"Virginia\u2013Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jamie L","family":"Stewart","sequence":"additional","affiliation":[{"name":"Virginia\u2013Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vitor R G","family":"Mercadante","sequence":"additional","affiliation":[{"name":"Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA"},{"name":"Virginia\u2013Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5404-3872","authenticated-orcid":false,"given":"Heather L","family":"Bradford","sequence":"additional","affiliation":[{"name":"Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2021,6,30]]},"reference":[{"key":"2021072416492227900_CIT0001","author":"AAA","year":"2021"},{"issue":"1","key":"2021072416492227900_CIT0002","doi-asserted-by":"crossref","first-page":"1","DOI":"10.18637\/jss.v067.i01","article-title":"Fitting linear mixed effects models using lme4","volume":"67","author":"Bates","year":"2015","journal-title":"J. Stat. Softw"},{"key":"2021072416492227900_CIT0003","author":"Beef Improvement Federation.","year":"2021"},{"issue":"1","key":"2021072416492227900_CIT0004","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1016\/j.livsci.2011.04.009","article-title":"Genetic parameters and relationships of heifer pregnancy and age at first calving with weight gain, yearling and mature weight in Nelore cattle","volume":"141","author":"Boligon","year":"2011","journal-title":"Livest. Sci"},{"key":"2021072416492227900_CIT0005","volume-title":"New technologies in animal breeding","author":"Brackett","year":"1981"},{"key":"2021072416492227900_CIT0006","doi-asserted-by":"crossref","first-page":"1119","DOI":"10.2527\/1994.7251119x","article-title":"Prepartum body condition and weight influences on reproductive performance on first-calf beef cows","volume":"72","author":"DeRouen","year":"1994","journal-title":"J. Anim. Sci"},{"key":"2021072416492227900_CIT0007","doi-asserted-by":"crossref","first-page":"1216","DOI":"10.2527\/jas1971.3261216x","article-title":"Influence of postbreeding thermal stress on conception rate in beef cattle","volume":"32","author":"Dunlap","year":"1971","journal-title":"J. Anim. Sci"},{"issue":"1","key":"2021072416492227900_CIT0008","first-page":"4","article-title":"Factors predicting the probability of estrus and pregnancy","author":"Goehring","year":"1987","journal-title":"Kansas Agric. Exp. Stat. Res. Rep"},{"key":"2021072416492227900_CIT0009","author":"Hartig","year":"2019"},{"key":"2021072416492227900_CIT0010","doi-asserted-by":"crossref","first-page":"E90","DOI":"10.2527\/2005.8313_supplE90x","article-title":"Nutritional controls of beef cow reproduction","volume":"83","author":"Hess","year":"2005","journal-title":"J. Anim. Sci"},{"issue":"5","key":"2021072416492227900_CIT0011","doi-asserted-by":"crossref","first-page":"1438","DOI":"10.2527\/1990.6851438x","article-title":"Effects of body composition, pre- and postpartum energy level and early weaning on reproductive performance of beef cows and preweaning calf gain","volume":"68","author":"Houghton","year":"1990","journal-title":"J. Anim. Sci"},{"key":"2021072416492227900_CIT0012","author":"Lenth","year":"2019"},{"key":"2021072416492227900_CIT0013","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1016\/S0301-6226(98)00158-4","article-title":"Evaluation of calving interval and calving date as a measure of reproductive performance in a beef herd","volume":"57","author":"MacGregor","year":"1999","journal-title":"Livest. Prod. Sci"},{"key":"2021072416492227900_CIT0014","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1093\/jas\/skz258.060","article-title":"Repeatability of estrus detection patch readings and relationship with breeding success","volume":"97","author":"Mercadante","year":"2019","journal-title":"J. Anim. Sci"},{"key":"2021072416492227900_CIT0015","doi-asserted-by":"crossref","first-page":"1138","DOI":"10.2527\/jas1982.5461138x","article-title":"Beef \u00d7 beef and dairy \u00d7 beef females mated to Angus and Charolais sires. I. Pregnancy rate, dystocia and birth weight","volume":"54","author":"Nelson","year":"1982","journal-title":"J. Anim. Sci"},{"key":"2021072416492227900_CIT0016","doi-asserted-by":"crossref","first-page":"22","DOI":"10.5713\/ajas.2011.11084","article-title":"Association of length of pregnancy with other reproductive traits in dairy cattle","volume":"25","author":"Nogalski","year":"2012","journal-title":"Asian-Australas. J. Anim. Sci"},{"key":"2021072416492227900_CIT0017","doi-asserted-by":"crossref","first-page":"1661","DOI":"10.2527\/1992.7061661x","article-title":"The effect of body condition, live weight, breed, age, calf performance, and calving date on reproductive performance of spring-calving beef cows","volume":"70","author":"Osoro","year":"1992","journal-title":"J. Anim. Sci"},{"key":"2021072416492227900_CIT0018","doi-asserted-by":"crossref","first-page":"1143","DOI":"10.1016\/0093-691X(93)90013-U","article-title":"Relationship of parity and body condition score to pregnancy rates in Florida beef cattle","volume":"39","author":"Rae","year":"1993","journal-title":"Theriogenology"},{"key":"2021072416492227900_CIT0019","doi-asserted-by":"crossref","first-page":"853","DOI":"10.2527\/1990.683853x","article-title":"Nutrition and postpartum rebreeding in cattle","volume":"68","author":"Randel","year":"1990","journal-title":"J. Anim. Sci"},{"issue":"2","key":"2021072416492227900_CIT0020","doi-asserted-by":"crossref","first-page":"300","DOI":"10.2527\/jas1986.622300x","article-title":"Effect of varying levels of postpartum nutrition and body condition at calving on subsequent reproductive performance in beef cattle","volume":"62","author":"Rickards","year":"1986","journal-title":"J. Anim. Sci"},{"issue":"12","key":"2021072416492227900_CIT0021","doi-asserted-by":"crossref","first-page":"3153","DOI":"10.2527\/jas1988.66123153x","article-title":"Relationships among weight change, body condition and reproductive performance of range beef cows","volume":"66","author":"Selk","year":"1988","journal-title":"J. Anim. Sci"},{"key":"2021072416492227900_CIT0022","doi-asserted-by":"crossref","first-page":"799","DOI":"10.2527\/1990.683799x","article-title":"Physiological mechanisms controlling anestrus and infertility in postpartum beef cattle","volume":"68","author":"Short","year":"1990","journal-title":"J. Anim. Sci"},{"key":"2021072416492227900_CIT0023","volume-title":"Dairy 2014, Health and management practices on U.S. dairy operations, 2014","author":"USDA.","year":"2018"},{"key":"2021072416492227900_CIT0024","volume-title":"Beef 2017, Beef cow-calf management practices in the United States, 2017, report 1","author":"USDA.","year":"2020"},{"key":"2021072416492227900_CIT0025","article-title":"Why are we challenged with the use of AI in southeastern USA commercial beef operations?","author":"Whittier","year":"2010"},{"key":"2021072416492227900_CIT0026","doi-asserted-by":"crossref","first-page":"219","DOI":"10.2527\/jas1962.212219x","article-title":"Effect of energy level on reproductive phenomena of mature Hereford cows","volume":"21","author":"Wiltbank","year":"1962","journal-title":"J. Anim. Sci"}],"container-title":["Translational Animal Science"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/academic.oup.com\/tas\/advance-article-pdf\/doi\/10.1093\/tas\/txab114\/38842860\/txab114.pdf","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"http:\/\/academic.oup.com\/tas\/article-pdf\/5\/3\/txab114\/39308549\/txab114.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"http:\/\/academic.oup.com\/tas\/article-pdf\/5\/3\/txab114\/39308549\/txab114.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,9,2]],"date-time":"2024-09-02T21:11:09Z","timestamp":1725311469000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/tas\/article\/doi\/10.1093\/tas\/txab114\/6311839"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,30]]},"references-count":26,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2021,7,1]]}},"URL":"https:\/\/doi.org\/10.1093\/tas\/txab114","relation":{},"ISSN":["2573-2102"],"issn-type":[{"value":"2573-2102","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2021,7,1]]},"published":{"date-parts":[[2021,6,30]]},"article-number":"txab114"}}