Genetic studies of sahiwal cows under Northern Indian plane condition for various economic traits

摘要

The age at first calving interval are important from the point of view of reproductive efficiency of a cow. Peak yield is one of the most important trait, that determines the lactation yield and the shape of the lactation curve. It can be used as a guide for selecting the bulls at early stages particularly in village conditions where total performance can not be recorded easily. The records of 805 Sahiwal cows progeny of 48 sires, maintained at Livestock Farm, Chakganjaria, Lucknow were distributedover a period of 42 years (1957-1998), according to year of first calving, located in Northern Indian plane, were utilized in this study. The records on cows with sire progeny group size of>6, and having normal calving with a lactation length of>150 daysand getting dry at their own were considered.