Giontella Andrea, Silvestrelli Maurizio, Cocciolone Alessandro, Pieramati Camillo, Sarti Francesca Maria
Department of Veterinary Medicine-Sportive Horse Research Center, University of Perugia, Via S. Costanzo 4, 06126 Perugia, Italy.
Department of Agricultural, Food and Environmental Sciences, University of Perugia, Borgo XX Giugno, 74, 06121 Perugia, Italy.
Animals (Basel). 2024 Jul 31;14(15):2232. doi: 10.3390/ani14152232.
Morphological scoring is a common evaluation method for domestic animals. The National Association of Maremmano Breeders (ANAM) has provided a dataset containing the records of 600 horses, four metric measurements (cm) and 24 traits with a continuous evaluation scale, each one with 15 classes. Moreover, a body condition score (BCS) with five classes is included. In this study, factor analysis was conducted to create a small number of informative factors (3) obtained from these traits, and a new BLUP-AM-MT index was established. The New Estimated Breeding Value (NEBV1) of each horse was computed by adding the genetic indexes of the three factors, with each one multiplied using a coefficient indicated by ANAM. The practical feasibility of the NEBV1 was evaluated through Spearman correlations between the rankings of the NEBV1 and the rankings of the BLUP-AM-MT, estimated through the four biometric measures and the morphological score (MS) assigned to each horse by the ANAM judges. The factorial analysis was used to estimate three factors: the "Trunk Dimension", "Legs" and "Length". As the explained variance was only 32%, the model was rotated, and the heritability of the three factors were 0.51, 0.05 and 0.41, respectively. After rotation, the estimated correlations between the new NEBV1 and the biometric measures were improved. These results should encourage breeders to adopt a breeding value index that takes into consideration the factors derived from all the variables observed in the morphological evaluation of the Maremmano. In this way, breeders can use it to select the best animals for breeding.
形态学评分是家畜常用的评估方法。马雷马诺 breeders 全国协会 (ANAM) 提供了一个数据集，其中包含 600 匹马的记录、四项度量测量（厘米）以及 24 个性状，这些性状具有连续评估量表，每个量表有 15 个等级。此外，还包括一个有五个等级的身体状况评分 (BCS)。在本研究中，进行了因子分析，以从这些性状中创建少量信息因子（3 个），并建立了一个新的 BLUP-AM-MT 指数。每匹马的新估计育种值 (NEBV1) 通过将三个因子的遗传指数相加来计算，每个因子都乘以 ANAM 指示的系数。通过 Spearman 相关性评估了 NEBV1 排名与 BLUP-AM-MT 排名之间的实际可行性，BLUP-AM-MT 排名是通过四项生物特征测量以及 ANAM 评委为每匹马分配的形态学评分 (MS) 来估计的。因子分析用于估计三个因子：“躯干尺寸”、“腿部”和“长度”。由于解释方差仅为 32%，因此对模型进行了旋转，三个因子的遗传力分别为 0.51、0.05 和 0.41。旋转后，新 NEBV1 与生物特征测量之间的估计相关性得到了改善。这些结果应鼓励育种者采用一种育种值指数，该指数考虑了从马雷马诺形态学评估中观察到的所有变量得出的因子。通过这种方式，育种者可以使用它来选择最佳的繁殖动物。
