Linear assessment and correlation of exterior features of Saanen goats

In order to calculate phenotypic and genetic correlations between exterior traits, as well as to construct linear profiles to identify the best male producers, a linear assessment of the exterior of Saanen goats was carried out on a farm in the Leningrad Region in June — July 2023 using a 9-point scale developed by the French Association of Dairy Goat Breeders. On average, for the studied population (n = 148), scores for the position of the back legs varied from 1 to 8 points and on average for the sample amounted to 4.5 points. The udder depth was estimated at 6.4 points on average, which corresponded to its optimal location for milking. The analysis of phenotypic and genetic correlation coefficients of linear exterior traits of the studied goat population revealed close reliable relationships between the scores of the front and back feet and legs. Genetic correlation coefficients generally corresponded to phenotypic ones, but in some cases had a greater degree of expression. The heritability of the external features of the studied population for indicators characterizing the quality of the udder and nipples ranged from h² = 0.108 for the “nipple shape” indicator to h² = 0.139 for the “udder groove” indicator, and in terms of leg quality — from h² = 0.122 for the hind legs to h² = 0.128 for the front hooves. Linear exterior profiles of bucks with more than 15 daughters evaluated in the herd were constructed, and reliable differences in the transmission of exterior characteristics between them were established, which can be further used in reproduction in order to obtain young animals with high exterior and constitutional development parameters.

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