Non-genetic influences on growth and efficiency traits in Tellicherry goats under semi-arid Tamil Nadu conditions

The present study was conducted to evaluate the influence of non-genetic factors on growth traits, average daily weight gain (ADG), growth efficiency (GE), and Kleiber ratio (KR) in Tellicherry goats under the natural and ecological conditions of the northeastern agro-climatic zone of Tamil Nadu, India. Data were collected from 354 Tellicherry kids reared at the Post Graduate Research Institute in Animal Sciences, Kattupakkam, over a five-year period (2018-2023). Body weights at birth, 3, 6, 9, and 12 months of age were recorded. ADG, GE, and KR were computed for pre-and post-weaning growth phases. The effects of non-genetic factors such as period and season of birth, sex, type of birth, and parity of dam were analyzed using a general linear model.    Results revealed that period of birth significantly influenced body weights, ADG, KR, and GE across all growth stages, likely due to variations in climatic and management conditions. Season of birth significantly affected weaning weight, ADG, and KR, with summer-born kids showing higher ADG and winter-born kids exhibiting superior KR. Sex had a marked effect on growth, with males outperforming females in terms of post-weaning ADG, KR, and GE. Type of birth influenced early body weights, with single and twin-born kids being heavier than triplets, though no significant impact was observed on ADG or KR. Parity of dam significantly affected post-weaning GE, with the highest efficiency observed during the third parity. In conclusion, the study highlights the substantial impact of non-genetic factors on growth and efficiency traits in Tellicherry goats. These findings underscore the importance of incorporating environmental and management variables into breeding and production strategies to improve overall goat productivity.