Estimation of Variance Components on Number of Kids Born in a Composite Goat Population

Abstract

Records on 1,487 parturitions from a composite population of Anglo-Nubian, Saanen, Native and crossbred goats at Yala Livestock Research and Breeding Center, Department of Livestock Development during the years 1995 and 2005 were estimated for variance components and parameters for number of kids born using REML procedure. Single-trait analysis included parity, year-season at kidding, covariates of additive and heterosis breed effects, direct genetic effects, permanent environmental and residual effects. The results showed that direct additive breed effects for Anglo-Nubian and Saanen as a measure of deviation from Native goats for the number of kids born were 0.02 and -0.09 heads, respectively. Heterosis breed effects in Anglo-Nubian ´ Native and Saanen ´ Native crosses were positive with increasing numbers of kids born at 0.11 and 0.31 heads, respectively. Direct heritability and permanent environmental variance as a proportion of phenotypic variance for number of kids born were found to be 0.04 and 0.02, respectively.

Keywords

• Breed effects
• variance component
• direct heritability
• permanent environmental effects
• number of kids born
• goats