Genetic studies of production efficiency traits and their uses in sire evaluation

Abstract

The information with respect to first lactation production and reproduction traits for each buffalo maintained at Network Project on Buffaloes, Livestock Research Station, Vallabhnagar from 1976 to 2004 were used for the present study. The MY/FLL and MY/FCI was significantly affected by sire, MY/FCI by period of calving and MY/FCI, MY/ ASC and MY/AFCON by season of calving. The heritability estimates for MY/FLL and MY/FCI were 0.343±0.145 and 0.199±0.125, respectively. Heritability estimates for MY/ASC and MY/AFCON were low. The genetic association of AFC with MY/FCI, MY/ASC and MY/AFCON was positive and high. The phenotypic correlation of AFC with MY/ ASC and MY/AFCON was negative and significant.
The genetic association of FSP and FCI with MY/FLL and MY/ASC was positive and low to moderate while with MY/FCI and MY/AFCON were negative and low to moderate. The phenotypic association of FSP and FCI with MY/ FCI, MY/ASC and MY/AFCON was negative and significant. The genetic and phenotypic correlation coefficients among production (FLMY, 305 MY and FPY) and production efficiency traits (MY/FLL, MY/FCI, MY/ASC and MY/ AFCON) were positive and moderate to high.
Among production efficiency traits maximum sires (47.83%) showed above average breeding value estimated by MY/FCI. The range as percentage of average breeding value was the maximum for breeding value estimated by MY/ ASC at 85.19%. Among the multi traits 46.37% sires showed breeding value more than average breeding value estimated by IVSI1. The breeding value estimated by IVSI1 also showed maximum (228.09%) range as percentage of average breeding value among all the traits under study. The rank correlation coefficients between single and multi traits were positive, high and significant. Considering the computational facilities required for construction of selection index, selection of sire can be made on the basis of MY/ASC with good reliability when selection index is not available.