Velie B D, Hamilton N A, Wade C M
Faculty of Veterinary Science, University of Sydney, Sydney, New South Wales, Australia.
Equine Vet J. 2016 May;48(3):275-9. doi: 10.1111/evj.12436. Epub 2015 May 26.
Many attempts have been made to improve the well-being of racing Thoroughbreds through improvements in management and veterinary care. However, these attempts are often limited by the industry's ability to regulate a large number of environmental variables and as a result have arguably had limited success in providing long-lasting change for the breed.
To identify heritable durability traits for Thoroughbred horses racing in Australia and Hong Kong.
Heritability analysis of a longitudinal dataset.
Performance data on the Thoroughbred populations racing in Australia and Hong Kong between 2000 and 2011 (n = 168,993) were used to estimate the heritabilities and probability values of fixed effects and covariates for a range of racing durability traits. Heritabilities for all durability traits were estimated using a single trait animal model. Each model included, as a minimum, the effects of sex and trainer.
Racing longevity (0.12 ± 0.01), racing persistence (0.10 ± 0.01), racing frequency (0.03 ± 0.01), spells (a time period between consecutive races, official trials and/or jump-outs greater than 90 days in length) per year (0.05 ± 0.01), spells per 10 starts (0.03 ± 0.01) and variation of days between races (0.08 ± 0.03) were all significantly heritable for horses racing in Australia. Racing longevity (0.08 ± 0.02), racing persistence (0.04 ± 0.02), spells per year (0.06 ± 0.02) and spells per 10 starts (0.11 ± 0.04) were significantly heritable for horses racing in Hong Kong.
The heritabilities estimated for durability traits in this study provide support for the successful and practical application of genetic selection methodologies to improving the well-being of racing Thoroughbreds.
人们已多次尝试通过改善管理和兽医护理来提高赛马用纯种马的健康水平。然而，这些尝试往往受到该行业调节大量环境变量能力的限制，因此在为该品种带来持久变化方面的成效有限。
确定在澳大利亚和香港参赛的纯种马的可遗传耐力性状。
对纵向数据集进行遗传力分析。
利用2000年至2011年间在澳大利亚和香港参赛的纯种马群体的性能数据（n = 168,993），估计一系列比赛耐力性状的遗传力以及固定效应和协变量的概率值。使用单性状动物模型估计所有耐力性状的遗传力。每个模型至少包括性别和驯马师的影响。
在澳大利亚参赛的马匹中，比赛寿命（0.12±0.01）、比赛持久性（0.10±0.01）、比赛频率（0.03±0.01）、每年的休赛期（连续比赛、官方试训和/或跳跃赛之间时长超过90天的时间段）（0.05±0.01）、每10次参赛的休赛期（0.03±0.01）以及比赛间隔天数的变化（0.08±0.03）均具有显著遗传性。在香港参赛的马匹中，比赛寿命（0.08±0.02）、比赛持久性（0.04±0.02）、每年的休赛期（0.06±0.02）以及每10次参赛的休赛期（0.11±0.04）具有显著遗传性。
本研究中估计的耐力性状遗传力为成功且实际应用基因选择方法来改善赛马用纯种马的健康水平提供了支持。
