Reproductive traits as an economical index in cattle breeding
1998
Strautmanis, D. (Latvian Univ. of Agriculture, Sigulda (Latvia). Research Centre "Sigra")
Reproductive traits in cattle husbandry are of great economical weight. There are such traits as animal fertility, calving performance, number of stillborn calves. All these traits affect the lenght between calvings and therefore also the cow's productivity. This paper presents the data of investigations on the number of stillborn calves depending on some genetic and environmental aspects. More than 6000 animals were included in these investigations. All the data are presented in four tables. It was established that heifers had 3.91-4.68 % stillborn calves and it was two times more than the old cows (P more than 0.999) had. This trait was influenced by herd where calves were born, by the sire and the breed.
显示更多 [+] 显示较少 [-]