Daborn Thomas, Pajor Edmond A, Pearson Jennifer M
University of Calgary Faculty of Veterinary Medicine, Calgary, AB T2N1N4, Canada.
Red Rock Ranch Vets, Cypress County, AB T1A1Z5, Canada.
Transl Anim Sci. 2025 Jun 14;9:txaf082. doi: 10.1093/tas/txaf082. eCollection 2025.
Currently, there is very little known about bull demographics and how bulls are managed on cow-calf operations in Alberta. Identifying these knowledge gaps will provide valuable insights on producer practices and potentially influence future management protocols that will improve bull management and the productivity of cow-calf operations. The objectives of this study were to benchmark beef bull herd demographics and bull management strategies in Alberta, Canada and to investigate associations between herd demographics and management strategies. Cow-calf producers were surveyed between February and August 2022 by paper or electronic copies of the survey. Fifty-two of 72 respondents were enrolled. Forty-two percent of the respondents were seedstock producers. The median female herd size exposed for breeding was 160 cows (IQR: 57 to 275; range: 14 to 1600) as reported by 43 respondents. The most common breed of bull used was Angus, followed by Hereford. The median number of bulls kept was 9, (IQR: 4 to 15; range: 1 to 71). Roughly 1 in 6 bulls were culled with the majority of bulls being culled or treated for conditions due to musculoskeletal or infectious foot causes. The median bull:cow ratio was 1:21 (IQR: 1:11 to 1:25) for heifers and 1:23 (IQR 1:20 to 1:26) for cows. The top 3 selection considerations for replacement bulls for breeding heifers was bull birthweight, bull EPD for calving ease, and physical appearance. The selection criteria for cows were bull adjusted weaning weight, physical appearance, and foot and leg conformation. This study contributes novel information on the breeding bull demographics and management strategies of cow-calf producers in Alberta. In addition, it identifies musculoskeletal issues as the major causes of treatment, death, and culling in bulls and recommends further investigation into causes and management strategies to mitigate these issues and improve bull health and welfare.
目前，对于艾伯塔省奶牛-犊牛养殖场的公牛种群统计信息以及公牛的管理方式，人们了解甚少。识别这些知识空白将为生产者的实践提供有价值的见解，并有可能影响未来的管理方案，从而改善公牛管理以及奶牛-犊牛养殖场的生产效率。本研究的目的是对加拿大艾伯塔省肉牛公牛群的种群统计信息和公牛管理策略进行基准评估，并调查牛群种群统计信息与管理策略之间的关联。2022年2月至8月期间，通过纸质或电子调查问卷对奶牛-犊牛生产者进行了调查。72名受访者中有52人参与了调查。42%的受访者是种畜生产者。据43名受访者报告，用于繁殖的母畜群规模中位数为160头母牛（四分位距：57至275头；范围：14至1600头）。使用最多的公牛品种是安格斯牛，其次是赫里福德牛。饲养的公牛数量中位数为9头（四分位距：4至15头；范围：1至71头）。大约六分之一的公牛被淘汰，大多数公牛因肌肉骨骼问题或足部感染而被淘汰或治疗。小母牛的公牛与母牛比例中位数为1:21（四分位距：1:11至1:25），母牛的比例为1:23（四分位距1:20至1:26）。用于繁殖小母牛的后备公牛的前三大选择考虑因素是公牛出生体重、公牛的产犊难易度预期子代差异（EPD）以及外貌。母牛的选择标准是公牛校正断奶体重、外貌以及蹄腿形态。本研究提供了有关艾伯塔省奶牛-犊牛生产者繁殖公牛种群统计信息和管理策略的新信息。此外，它确定肌肉骨骼问题是公牛治疗、死亡和淘汰的主要原因，并建议进一步调查其原因和管理策略，以减轻这些问题并改善公牛的健康和福利。
