Genetic parameters Estimation of Growth and Fleece Weight in Iranian Markhoz Goats
Subject Areas : Journal of Large Animal Clinical Science Research(JLACSR)
Keywords: heritability, fleece weight, growth traits, genetic correlation, Markoz goat,
Abstract :
The aim of this study was to estimate genetic and environmental (Co) variance components and genetic parameters for growth traits including birth weight (BW), weaning weights (WW), 6.month weight (W6), 9.month weight (W9), 12.month weight (W12) and fleece weight (FW) in Markhoz goats. Data were collected over a period of 17 years (1991–2008) in Markhoz goats maintained at the central goat institute, Sanandaj, Iran. GLM procedure was carried out for selection the fixed and covariate effects affecting traits. Analysis were carried out by restricted maximum likelihood using AS-REML program. Six different animal models with various combinations of direct and maternal effects were fitted and best model was chosen by comparison of the log-likelihood values. The best model for BW, WW and W6 was the model with direct and maternal additive genetic and permanent environmental effects (Model 7) and for W9, W12 and FW was model 1 with only direct genetic effect. Heritability estimates for BW, WW, W6, W9, W12, FW, were 0.22±0.07, 0.18±0.06, 0.20±0.07, 0.35±0.08, 0.29±0.07, 0.07±0.03, respectively. The highest genetic correlation was estimated between W6 with W9 and lowest was related to BW and W12. On the other hand highest negative correlation was between W6 and FW. The maternal effects had a significant role in growth traits and its effect was decreased with increasing the age. Also the weaning weight can be as good criteria in improving the growth traits.
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