LINEAR TYPE TRAITS FOR FEET AND LEGS, THEIR RELATION TO HEALTH TRAITS CONNECTED WITH THEM, AND WITH PRODUCTIVE AND REPRODUCTIVE TRAITS IN DAIRY COWS

Rumen Binev, Tchonka Miteva, Zhivka Gergovska, Toncho Penev, Dimo Dimov, Jurii Mitev, Ivilo Marinov

Abstract: The objective of the study was to estimate the correlations between linear type traits for feet and legs, and their relation with locomotion disorders and productive and reproductive traits in Holstein cows reared in Bulgaria. The study included 136 cows from four dairy farms of different regions of Bulgaria. In all farms, cows were year-round reared group in free stalls with individual boxes for rest. In the study 7 linear type traits for feet and legs and the trait heel depth were included. On cows also a lameness scoring on a scale of 1 to 4 was carried out. Phenotypic correlations between linear traits were low. In cows with wider and parallel placed rear legs a tendency to straighter hock (-0.20) was reported, which was associated with a steeper foot (-0.16) and flatter hocks (-0.18). Cows with thicker bones and steeper foot (0.24) had and deeper heel (-0.24). When selection for thinner bones and optimal foot angle is conducted, it would be likely the heel depth to decline. Cows with straighter hock (-0.16), lower foot angle (0.18), shallower heel (-0.25) and better locomotion (0.25) had higher milk yield for 305 days. The selection for higher milk yield will be associated with a tendency for unfavorable phenotypic deviations in the various linear traits for feet and legs, with the exception of bone structure and locomotion. Cows with more pronounced X-shaped rear legsrear
view (-0.18), with flatter and dry hocks (0.16) and with thicker bones (-0.25) had longer interval from calving to first insemination. Cows with thicker bones had smaller number of inseminations for conception (0.20). The phenotypic correlations between clinical problems with feet and legs and linear traits were with low values (from -0.01 to 0.10). With the highest and negative value was the phenotypic correlation between linear trait locomotion and clinical problems with legs and feet (-0.37). Using only the linear traits for feet and legs to reduce the locomotive problems, without additional information about the various
clinical problems with legs and feet will not have a considerable effect.

Keywords: dairy cows; lameness; linear type traits; locomotion; productivity; reproduction

Date published: 2017-07-07