Estimation of First Lactation Milk Yield on the Basis of Part Lactation Milk Yield in Murrah Buffaloes

Abstract

A total number of 222 performance records of murrah buffaloes progeny of 53 sires at the Central Institute For Research on Buffalo Hisar (Haryana), over a period of 16 years from 1986 to 2001 (years of first calving) were used to study the effect of seasons and years on cumulative part lactation milk yield. The genetic and non-genetic parameters of cumulative part lactation milk yield and the first lactation production traits and to predict the 305 days milk yields on the basis of cumulative part lactation milk yield.viz. The effect of season were found to be non-significant on cumulative part lactation milk yield as reported by Khan and Johar (1988), lype and Nagarcanker (1992) and yadav et al. (2003) The effect of years on cumulative part lactation milk yields were found to be highly significant as reported by Khan and Johar (1988), lype and Nagarcanker (1992) and Yadav et al. (2003). The heritability estimates for cumulative part lactation milk yield and for first lactation production traits were found in a range of 0.074±0.65 (30 days milk yield) to 0.185±0.052 (120 days milk production) and from 0.001±0.188 (first lactation milk yield ) to 0.042±0.288 (first service period) , respectively. The heritability of ?umulative part lactation milk yield in earlier stages have higher magnitude than middle and later stages of lactation and showed more additive genetic effect. Appannayar et al. (1995) also reported heritability estimates of the cumulative test day milk yields in arrange of 0.15±0.17 to 0.39±0.28. The genetic and phenotypic correlations among cumulative part lactation milk yields were a ranged from 0.572±0.020 (between 30days and 240 days milk yield) and from 0.502±0.288 (between 30 days and 240 days milk yield) to 0.999±0.002 (between 150 days and 180 days milk yield), respectively. Dass (1995) and Geetha (2006) also reported the high positive and significant genetic and phenotypic correlations among the adjacent test day milk yield. The genetic and phenotypic correlations among first lactation production traits were ranged from 0.017±0.937 (between first calving and dry period) to 0.995±0.007 (between age at first calving and service period) and from -0.080 to 0.991 between age at first calving and dry period and service period, respectively The prediction of 305 days lactation milk yield on the basis of cumulative part lactation milk yield showed the higher value of R2 (78.70%) for 240 days and lower value of R2 (12.92%) for 30 days of cumulative part lactation milk yield. However, significant differences were not found for 60, 90, 120, 150, 180, 210, 240 and 270 days of cumulative part lactation milk yield. The R2 values indicate that the animals for milk yield can be selected earlier on the basis of 60, 120, 150, 180, 240 and 270 days of cumulative part lactation milk yield.