ORIGINAL RESEARCH Estimates of (co)variance components and genetic parameters for growth traits in Sirohi goat Gopal R. Gowane & Ashish Chopra & Ved Prakash & A. L. Arora Accepted: 2 August 2010 / Published online: 15 August 2010 # Springer Science+Business Media B.V. 2010 Abstract Data were collected over a period of 21 years (1988–2008) to estimate (co)variance components for birth weight (BWT), weaning weight (WWT), 6-month weight (6WT), 9-month weight (9WT), 12-month weight (12WT), average daily gain from birth to weaning (ADG1), weaning to 6WT (ADG2), and from 6WT to 12WT (ADG3) in Sirohi goats maintained at the Central Sheep and Wool Research Institute, Avikanagar, Rajasthan, India. Analyses were carried out by restricted maximum likelihood, fitting six animal models with various combinations of direct and maternal effects. The best model was chosen after testing the improvement of the log-likelihood values. Heritability estimates for BWT, WWT, 6WT, 9WT, 12WT, ADG1, ADG2, and ADG3 were 0.39±0.05, 0.09±0.03, 0.06±0.02, 0.09±0.03, 0.11±0.03, 0.10±0.3, 0.04±0.02, and 0.01± 0.01, respectively. For BWT and ADG1, only direct effects were significant. Estimate of maternal permanent environ- mental effect were important for body weights from weaning to 12WT and also for ADG2 and ADG3. However, direct maternal effects were not significant throughout. Estimate of c 2 were 0.06±0.02, 0.03±0.02, 0.06±0.02, 0.05±0.02, 0.02±0.02, and 0.02±0.02 for 3WT, 6WT, 9WT, 12WT, ADG2, and ADG3, respectively. The estimated repeatabilities across years of ewe effects on kid body weights were 0.10, 0.08, 0.05, 0.08, and 0.08 at birth, weaning, 6, 9, and 12 months of age, respectively. Results suggest possibility of modest rate of genetic progress for body weight traits and ADG1 through selection, whereas only slow progress will be possible for post-weaning gain. Genetic and phenotypic correlations between body weight traits were high and positive. High genetic correlation between 6WT and 9WT suggests that selection of animals at 6 months can be carried out instead of present practice of selection at 9 months. Keywords Growth . Direct heritability . Genetic correlation . Maternal effects . Sirohi goat Introduction The developing countries owned about 98% of the goat population and 76% share of the breeds, where, over 30 indigenous “improved breeds” exist that are under-utilised and potentially important (Devendra 2010). The importance of goats is increasing due to low input production system. Sirohi is the dual-purpose goat breed of Rajasthan, known for its agile look, with white spots on brown colored body and famous for chevon and milk production. Goat production is the major occupation of rural people especially in the semi-arid region of India. Goats are the best animal for meat industry due to their hardiness, disease resistance, prolificacy, and no socio-religious barrier for meat consumption. Sirohi goats are native of the Sirohi, Nagaur, Jhunjhunu, and adjoining areas of Rajasthan, but they can survive in many diverse climatic conditions in other areas too. Sirohi goats are reared by small and marginal farmers who graze them on fallow land and crop residue. They are mainly reared for chevon purpose, but income from sale of milk is also significant as on average Sirohi goat yields 933 g milk per day in the first 90 days of lactation (Shinde et al. 2008). A flock of around 300 Sirohi goats is maintained at the Central Sheep and Wool Research Institute Avikanagar, Rajasthan, India, on a semi-intensive G. R. Gowane (*) : A. Chopra : V. Prakash : A. L. Arora Animal Genetics and Breeding Division, Central Sheep and Wool Research Institute, Avikanagar-304501, via- Jaipur, Rajasthan, India e-mail: gopalgowane@gmail.com Trop Anim Health Prod (2011) 43:189–198 DOI 10.1007/s11250-010-9673-4