Wijma Robert, Weigel Daniel J, Vukasinovic Natascha, Gonzalez-Peña Dianelys, McGovern Shaileen P, Fessenden Brenda C, McNeel Anthony K, Di Croce Fernando A
Zoetis Inc., 333 Portage Street, Kalamazoo, MI 49007, USA.
Animals (Basel). 2022 Aug 15;12(16):2079. doi: 10.3390/ani12162079.
Abortion in dairy cattle causes great economic losses due to reduced animal health, increase in culling rates, reduction in calf production, and milk yield, among others. Although the etiology of abortions can be of various origins, previous research has shown a genetic component. The objectives of this study were to (1) describe the development of the genomic prediction for cow abortions in lactating Holstein dairy cattle based on producer-recorded data and ssGBLUP methodology and (2) evaluate the efficacy of genomic predictions for cow abortions in commercial herds of US Holstein cows using data from herds that do not contribute phenotypic information to the evaluation. We hypothesized that cows with greater genomic predictions for cow abortions (Z_Abort STA) would have a reduced incidence of abortion. Phenotypic data on abortions, pedigree, and genotypes were collected directly from commercial dairy producers upon obtaining their permission. Abortion was defined as the loss of a confirmed pregnancy after 42 and prior to 260 days of gestation, treated as a binary outcome (0, 1), and analyzed using a threshold model. Data from a different subset of animals were used to test the efficacy of the prediction. The additive genetic variance for the cow abortion trait (Z_Abort) was 0.1235 and heritability was 0.0773. For all animals with genotypes (n = 1,662,251), mean reliability was 42%, and genomic predicted transmitting abilities (gPTAs) ranged from −8.8 to 12.4. Z_Abort had a positive correlation with cow and calf health traits and reproductive traits, and a negative correlation with production traits. Z_Abort effectively identified cows with a greater or lesser risk of abortion (16.6% vs. 11.0% for the worst and best genomics groups, respectively; p < 0.0001). The inclusion of cow abortion genomic predictions in a multi-trait selection index would allow dairy producers and consultants to reduce the incidence of abortion and to select high-producing, healthier, and more profitable cows.
奶牛流产会导致巨大的经济损失，原因包括动物健康状况下降、淘汰率上升、犊牛产量和产奶量减少等。尽管流产的病因可能多种多样，但先前的研究表明存在遗传因素。本研究的目的是：（1）基于生产者记录的数据和ssGBLUP方法，描述泌乳期荷斯坦奶牛流产的基因组预测的发展；（2）使用未为评估提供表型信息的牛群数据，评估美国荷斯坦奶牛商业牛群中奶牛流产基因组预测的有效性。我们假设，奶牛流产基因组预测值较高（Z_Abort STA）的奶牛流产发生率会降低。在获得商业奶牛生产者的许可后，直接从他们那里收集了流产的表型数据、系谱和基因型。流产被定义为妊娠42天后至260天前确诊妊娠的丢失，作为二元结果（0,1）处理，并使用阈值模型进行分析。来自不同动物子集的数据用于测试预测的有效性。奶牛流产性状（Z_Abort）的加性遗传方差为0.1235，遗传力为0.0773。对于所有有基因型的动物（n = 1,662,251），平均可靠性为42%，基因组预测传递能力（gPTAs）范围为−8.8至12.4。Z_Abort与奶牛和犊牛健康性状以及繁殖性状呈正相关，与生产性状呈负相关。Z_Abort有效地识别出流产风险较高或较低的奶牛（最差和最佳基因组组分别为16.6%和11.0%；p < 0.0001）。将奶牛流产基因组预测纳入多性状选择指数，将使奶牛生产者和顾问能够降低流产发生率，并选择高产、更健康和更盈利的奶牛。
