Biophysical qualities of the hoof horn and its influence on cows productive longevity

¹ Samara State Agrarian University, 2, st. Educational, 446442, Kinel, Russia
² Penza State Agrarian University, 30, st. Botanical, 440014, Penza, Russia

^* Corresponding author: KaramaevSV@mail.ru

Abstract

The main research objective was to study the influence of the hoof shape, hardness and elasticity of the hoofed horn on the cows’ productive use period duration in modern dairy complexes. The research object was black-motley cows, rejected due to limb disease. The shape of the hoof is divided into normal, with angle of 45-55^о, sharp – less than 45^о and obtuse – more than 55^о. In the group of retired cows with the correct shape, there was 76% of animals. Studies have shown that 55.2% of cows had a hoof hardness 80-85 ShA, but the longest period of life was in animals with a score of 91 or more ShA, and the maximum lifetime milk yield with an indicator 86-90 ShA. Most of (61,6%) retired cows had an indicator of hoof horn elasticity 3,1-3,5×10¹⁰ Pa. Moreover, the highest rates of productive longevity were observed in cows with hoof horn elasticity 2,6-3,0×10¹⁰ Pa. Therefore, for further use, it is desirable to select animals having front wall inclination angle of the hoof 50-55⁰, with hardness hoofed horn 86-90 ShA, and elasticity 2,6-3,0×10¹⁰ Pa.