The relationships between body weight, testicular weight, age and the scrotal circumference of goats in the semi-arid Maiduguri, Nigeria

Abstract

The relationships between body weight, testicular weight, age and the scrotal circumference were analysed in 62 bucks made up of the Sahel (S), Red Sokoto (RS) and West African Dwarf (WAD) breeds and aged three to nine months. Scrotal circumference increased with age; ranging from 9.87 to 13.35 cm. The effects of breed, season, parity and litter size were significant (p<0.05) at late post-weaning ages, while, year effect was not significant (p>0.05). At these ages, S and RS had similar scrotal circumference, though, both were superior to WAD. Heritability and repeatability estimates were moderate to high. Genotypic and phenotypic correlations of scrotal circumference with body weight and testicular weight were generally high and positive. However, the scrotal circumference had higher correlation with testicular weight than body weight. Based on the genetic parameters, scrotal circumference can be improved by direct selection with a correlated response from testicular weight and body weight.

Keywords: Goats, testicular weight, scrotal circumference, bucks, Nigeria