Lane E A, Bijnen M L J, Osborne M, More S J, Henderson I S F, Duffy P, Crowe M A
Centre for Veterinary Epidemiology and Risk Analysis, University College Dublin, Belfield, Dublin 4, Ireland.
UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
Reprod Domest Anim. 2016 Apr;51(2):181-7. doi: 10.1111/rda.12655. Epub 2016 Jan 27.
To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4-15 years) had bred 2385 mares (mean age 9.4 years; range 3-24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk-in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post-partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting.
为评估影响纯种母马繁殖力的因素，在爱尔兰的一个大型纯种马场收集了2385匹母马3743个发情期的数据。14匹种马（平均年龄8.3岁；范围4 - 15岁）与2385匹母马（平均年龄9.4岁；范围3 - 24岁）配种。初产母马占总数的12%，有驹母马占64%，不育、流产或休情母马占24%。每个周期的平均妊娠率为67.8%（第1年为68.6%，第2年为66.9%）。采用向后逐步多变量逻辑回归分析建立两个模型，以评估母马因素，包括母马年龄、繁殖状态、产驹月份、难产、配种月份、产后发情、周期数、治疗情况、入厩状态，以及种马因素，包括种马身份、种马年龄、穿梭状态、两次配种间隔时间和种马高使用频率对每个周期妊娠率和妊娠丢失的影响。老龄（p < 0.001）和产后20天内配种（p < 0.003）与妊娠率降低有关。母马年龄较大（p < 0.05）以及不育、流产或休情的繁殖状态（p = 0.05）会增加妊娠丢失的可能性。子宫炎症或感染若得到适当治疗，不影响繁殖力。只有种马高使用频率（前一周使用超过21次）与妊娠率降低有关（p = 0.009）。然而，穿梭种马的妊娠存活可能性更高（p = 0.035），这可能反映了种马选择上的偏差。总之，母马年龄对繁殖力影响最大；尽管如此，在商业环境中，纯种马可以通过有效管理实现高繁殖性能。
