Genetic and non-genetic causes of variation in gestation length, litter size and litter weight in goats

Abstract

This study was made with 631 does of 3 genetic groups and 1,112 of their kids allocated into 3 different locations to examine gestation length, litter size and litter weight in goats. Attributes studied were genetic group, parity, age of dam at kidding, weight of dam at breeding, season and location. Genetic group of dam affected significantly (p<0.01) size of litter but not gestation length and weight of litter. Selected Black Bengal (SBB) genetic group performed better in litter size and litter weight than random bred Black Bengal (RBB) and its crossbreds with Jamunapari ♂ (JBB). Litter size and weight were significantly affected by age of dam at kidding (p<0.01), weight of dam at service (p<0.001) and parity (p<0001). Size and weight of litter were found highest in SBB does, or does having 35-40 months of age at kidding, or does with 19-20 kg live weight at service, or at 4th parity. Season, location and parity also affected significantly (p<0.05) gestation length. Shortest gestation length was found in 5th parity or in summer season, whereas the longest was in 2nd parity or in winter season.