Gifford Craig A, Taylor Keegan M, Spiegal Sheri, Duff Glenn C, Aney Skye, Elias Emile, Steiner Jean L, Estell Rick, McFarlane Zach D, Schohr Tracy K, DeAtley Kasey L, Banwarth Megan R
Extension Animal Sciences and Natural Resources, New Mexico State University, Las Cruces, NM 88001, USA.
USDA Agricultural Research Service - Jornada Experimental Range, Las Cruces, NM 88003, USA.
Transl Anim Sci. 2022 Dec 22;7(1):txac167. doi: 10.1093/tas/txac167. eCollection 2023 Jan.
There were 463,000 head of beef cows in New Mexico as of January 1, 2021 (NASS, 2020), down roughly 4% from 2020 (NASS, 2019). Frequent drought often results in herd reduction and loss of valuable genetic progress. Bull selection is critical due to their influence on herd development. A survey was conducted to identify traits important to bull selection in New Mexico. Surveys were collected digitally ( = 83) and via the mail ( = 74). Responses were largely by cow/calf producers averaging 57 ± 1 years old with 24 ± 1 years' experience. Survey respondents represented 4,384,296 acres of private owned, private leased, and leased public rangeland and irrigated pasture meadow in New Mexico and surrounding states. Average cow/calf operation size was 294 ± 39 head and average bull herd size was 21 ± 3 head. Average price paid for a bull in the past 2 years was $3,981 ± 213. Physical characteristics, individual bull performance information, and genetic information are all important traits to New Mexico bull buyers; however, most producers (56%) indicated that structural soundness was the most important factor influencing their selection decisions. Amongst expected progeny differences (EPDs), New Mexico producers consider the calving ease direct (CED) and birth weight (BW) EPDS to be most important (40% and 35%, respectively). Producers also indicated that multitrait selection indexes used by the American Angus Association were important to their selection decisions, with the beef value ($B) and weaned calf value ($W) indexes being cited most often (35% and 31%, respectively). Elements important to bull purchase include the bull's sale preview (87%), body condition score (86%), feed efficiency/average daily gain information (85%), and actual scrotal circumference (82%). Following purchase of a new bull, most (60%) keep the bull separate from the cow herd until the following breeding season, while the remaining 40% of producers turn newly purchased bulls out within 30 days of purchase. Sixty eight percent of producers evaluate semen quality annually or prior to the start of the breeding season. Interestingly, 39% of producers indicated they used reproductive technologies like artificial insemination and synchronization of estrus while most (80%) test for trichomoniasis. The primary factor influencing culling decisions is age, followed by soundness and fertility.
截至2021年1月1日,新墨西哥州有46.3万头肉用母牛(美国国家农业统计局,2020年),比2020年(美国国家农业统计局,2019年)减少了约4%。频繁的干旱常常导致牛群数量减少以及宝贵的遗传进展丧失。公牛的选择至关重要,因为其对牛群发展有影响。开展了一项调查,以确定新墨西哥州公牛选择中重要的性状。调查通过数字方式(n = 83)和邮寄方式(n = 74)收集。回复者主要是母牛/犊牛生产者,平均年龄为57 ± 1岁,有24 ± 1年的经验。调查对象代表了新墨西哥州及周边各州4384296英亩的私有、私人租赁以及租赁的公共牧场和灌溉牧场草地。母牛/犊牛养殖场的平均规模为294 ± 39头,公牛群的平均规模为21 ± 3头。过去两年购买一头公牛的平均价格为3981 ± 213美元。身体特征、个体公牛性能信息和遗传信息对新墨西哥州的公牛买家而言都是重要性状;然而,大多数生产者(56%)表示结构健全是影响他们选择决策的最重要因素。在预期子代差异(EPDs)中,新墨西哥州的生产者认为产犊难易度直接效应(CED)和出生体重(BW)的EPD最为重要(分别为40%和35%)。生产者还表示,美国安格斯协会使用的多性状选择指数对他们的选择决策很重要,其中牛肉价值($B)和断奶犊牛价值($W)指数被提及的频率最高(分别为35%和31%)。购买公牛时重要的因素包括公牛的销售预览(87%)、体况评分(86%)、饲料效率/平均日增重信息(85%)以及实际阴囊周长(82%)。购买新公牛后,大多数(60%)会将公牛与母牛群分开,直到下一个繁殖季节,而其余40%的生产者会在购买后30天内将新购买的公牛放入牛群。68%的生产者每年或在繁殖季节开始前评估精液质量。有趣的是,39%的生产者表示他们使用人工授精和发情同步等繁殖技术,而大多数(80%)会检测滴虫病。影响淘汰决策的主要因素是年龄,其次是健全程度和繁殖力。