Ricard Anne, Dumont Saint Priest Bernard, Danvy Sophie, Barrey Eric
Université Paris-Saclay, INRAE, AgroParisTech, GABI, Jouy-en-Josas, France.
Pole Développement Innovation Recherche, IFCE, Gouffern en Auge, France.
Front Genet. 2020 May 19;11:448. doi: 10.3389/fgene.2020.00448. eCollection 2020.
The aim of this study was to evaluate the genetic component of the locomotor jumping ability, via a wearable accelerometer sensor, and to estimate the genetic correlation with performance in competition, to introduce such criteria in selection schema. A sample of 1,056 young 3-year-old horses were equipped with a 3-dimensional accelerometer during a free jumping test, in regular breeding shows from 2015 to 2017. Seven variables were extracted from the dorso-ventral acceleration curve for the last three jumps over a double bar obstacle of 1.15 m for the front pole and 1.20 m for the back pole with a 1.20 m spread. Variables were the peaks of forelimbs, hindlimbs, and landing acceleration, the duration between peaks at take-off, the peak of forelimb acceleration and start of jump, jump duration and duration between the beginning of the impact of forelimbs and the peak at landing. During breeding shows, judges scored balance, strength, style, and reactivity for free jumping and jumping tests under saddle. Jumping competition results were recorded by logarithm of the sum of points earned in each competition. All horses in official competitions were included, i.e., 160,257 horses born in 1997 with a total of 649,491 annual performances. An animal mixed model with complete pedigree over four generations (353,236 horses) were used with fixed effects of jumping test location and date, morning/afternoon, gender, month of birth, rank of jump for accelerometric data, effect of year of competition, combined with age and gender for competition results. As a result, jump duration was the most heritable and repeatable for jump variables: = 0.16 (0.06), = 0.52 (0.02), while accelerations were moderately heritable ( = 0.05-0.09, = 0.39-0.51). Judgement scores were heritable: 0.21 (0.07)-0.33 (0.09) and were highly correlated. Scores during free jumping were genetically correlated to jump duration: 0.71 (0.15)-0.88 (0.16). Both jump duration and judgement scores were genetically correlated to competition performance: 0.59 (0.13) for jump duration, from 0.60 (0.11) to 0.77 (0.12) for scores. Jump duration and judgement scores can be used as early selection criteria. The advantage of the accelerometric measurement is its objectivity and the ease of recording.
本研究的目的是通过可穿戴加速度计传感器评估运动跳跃能力的遗传成分，并估计与比赛成绩的遗传相关性，以便在选择方案中引入此类标准。在2015年至2017年的常规育种展览中，对1056匹3岁的年轻马匹进行了自由跳跃测试，期间为它们配备了三维加速度计。从背腹加速度曲线中提取了七个变量，这些变量来自于在一个双杆障碍上的最后三次跳跃，该障碍前杆高1.15米，后杆高1.20米，杆间距为1.20米。变量包括前肢、后肢和着陆加速度的峰值、起跳时峰值之间的持续时间、前肢加速度峰值与跳跃开始之间的时间、跳跃持续时间以及前肢着地开始到着陆峰值之间的持续时间。在育种展览期间，评委们对自由跳跃和鞍上跳跃测试的平衡、力量、风格和反应能力进行评分。跳跃比赛成绩通过每场比赛所得分数总和的对数来记录。官方比赛中的所有马匹都被纳入，即1997年出生的160257匹马，共有649491次年度表现。使用了一个包含四代完整系谱（353236匹马）的动物混合模型，其中固定效应包括跳跃测试地点和日期、上午/下午、性别、出生月份、加速度计数据的跳跃排名、比赛年份的影响，以及比赛成绩的年龄和性别组合。结果显示，对于跳跃变量，跳跃持续时间的遗传性和重复性最高：遗传力（h²）= 0.16（0.06），重复性（r）= 0.52（0.02），而加速度的遗传性中等（h² = 0.05 - 0.09，r = 0.39 - 0.51）。评判分数具有遗传性：0.21（0.07）- 0.33（0.09），且高度相关。自由跳跃时的分数与跳跃持续时间存在遗传相关性：0.71（0.15）- 0.88（0.16）。跳跃持续时间和评判分数与比赛成绩均存在遗传相关性：跳跃持续时间的遗传相关系数为0.59（0.13），分数的遗传相关系数为0.60（0.11）至0.77（0.12）。跳跃持续时间和评判分数可作为早期选择标准。加速度测量的优点是其客观性和记录的简便性。
