INFLUENCE OF INTERLINEAR DIFFERENCES ON HOLSTEIN COWS PERFORMANCE
The purpose of the study was to determine the productive qualities of Holstein cows of different genotypes. The study was conducted under the conditions of OOO “Agro-Soyuz” of the Kabardino-Balkar Republic from 2012 to 2016. The genealogical composition of the cattle population under study was represented by two lines of bulls: Wis Beck Idial 933122 and Reflection Sovering 198998. All the cows of the herd were descendants of three bulls: Ray-Mar Legend 139164598 (n=191), Pylot 6381114 (n=186) and Sharki 131184495 (n=256). The data of zootechnical and pedigree records of the whole cow population have been analyzed. The milk yield recording was carried out using the method of daily control milking with the “Karusel” milking units. The content of fat and protein in milk has been determined. The results of the study showed that the inter-linear differences in milk yield indices of purebred Holstein cows of the LLC “Agro-Soyuz” were less expressed than the intralinear ones, which must be taken into account in the future selective-breeding works, when selecting sire-bulls for the herd.