Genetic and environmental factors affecting growth traits of goats in semi arid area of Nigeria.

摘要

This study was conducted to determine the effect of genetic and environmental factors on growth performance of 194 Sahel (S), Red Sokoto (RS) and West African Dwarf (WAD) kids from birth to 9 months old. Results revealed that the effect of breed was significant (p<0.001) with S (2.07 kg-13.49 kg) being the heaviest when compared with RS (1.81 kg-13.77 kg) and WAD (1.42 KG-8.63 kg), though were comparable with RS at 9 months old. WAD had the lowest body weight at all ages. Seasonal effect showed that animals born during the wet season were significantly (p<0.001) heavier than those born during the dry season at the early ages, while those born during the dry cold were heavier at the late ages. Litter size and sex also affected body weights. Single birth (1.96 kg-13.64 kg) and male (1.88 kg- 12.64 kg) kids had significantly heavier weights when compared with multiple birth (1.66 kg-12.33 kg) and female (1.67 kg-11.28 kg) kid, respectively. S (56.33 g/day) and RS (56.22 g/day) had similar preweaning average daily gain but, both significantly gained more weight (p<0.001) than WAD (35.31 g/day). Red Sokoto, however gained more than S at postweaning stage, while WAD still had the lowest (p<0.001) gain. The effect of season on preweaning gain followed the same trend as body weights. The effect of parity, litter size and sex on rate of gain, which significantly (p<0.01) favoured fourth parity, single and male kids, respectively, at the preweaning stage were not significant during the postweaning stages. It is suggested that the growth of Nigerian goat breeds is generally low. Effort is required to provide standard environment, particularly during the preweaning stages, for improved productivity. In addition, before selection, adjustment is needed for any factors that affect performance.