Studies on Productive and reproducative performance of Frieswal Cattle

Abstract

A total number of 5125 lactation records of 1768 Frieswal cows, sired by 87 sires born and reared at Military Dairy Farm, Meerut, over a period of 20 years extending from 1991 to 2010 were used to study the average performance of production and reproduction traits, effect of genetic and non-genetic factors on production and reproduction traits and estimation of genetic and phenotypic parameters of production and reproduction traits. The least squares means of age at first calving, total lactation milk yield, 300 days milk yield, peak yield, lactation length, dry period, calving interval and service period were 937.10±5.69 days, 3435.59±66.09 kg, 3409.12±36.69 kg15.58±0.27 kg, 350.33±5.54 days,131.41±7.09 days, and 452.24±8.08 days, respectively. The age at first calving differed significantly across the periods of calving. The AFC was shortest (838.55±25.08 days) in fifth period (2007 -201 0) and longest (1 016.36±1 0.87days) in second period (1995- 98). The effect of season and period of calving, lactation order and regression of age at first calving on total lactation milk yield, 300 days milk yield, peak yield, lactation length, dry period, calving interval and service period was highly significant.The sires was not found to have significant effect on any trait under study. Total lactation milk yield was highest in cows calved during winter season (3530.75±68.48 kg), third period (3585.01 ± 75.44 kg) and in fourth lactation (3655.46±73.05 kg). The average 300 days milk yield was highest in the cows calved in summer season (3478.74±41 .78), third period (3646.18±46.46 kg) and in sixth lactation (3789.19±1 01 .73). The heritability estimates were low for almost all the traits under study. The heritability estimates for age at first calving, total lactation milk yield, 300 days milk yield, peak yield, lactation length, dry period, calving interval and service period was 0.09±0.04, 0.1 0±0.03, 0.12±0.36, 0.12±0.03, 0.035±0.016, 0.08±0.03,0.05±0.025 and 0.06±0.025 respectively Total lactation milk yield had high genetic correlation with peak yield (0.96±0.03) low (0.323±0.299) with lactation length. Peak yield had low genetic correlation (0.16±0.23) with lactation length. The service period had high genetic correlation with dry period (0.086±0.1 0) and calving interval (0.96±0.03).The dry period also found to have high genetic correlation (0.94±0.07) with calving interval in Frieswal cows. The phenotypic correlation of total lactation milk yield was high (0. 779) with peak yield and low (0.244) with lactation length. The peak yield had very low phenotypic correlation (0.06) with lactation length. Service period had high phenotypic correlation (0. 70) with dry period and very high (0.93) with calving interval. High phenotypic correlation (0. 78) was also observed between dry period and calving interval.