Growth Traits and Estimated Heritability by Variance Component for Dhofari Calf Breed

Abstract

Dhofari calf breed weight variations at similar age indicate their potentiality for genetic improvement by careful selection. The present study was carried out to find the average growth traits of birth weight (BW), weaning weight(WW), yearling weight(YW), pre-weaning daily gain(PRE), post-weaning daily gain(POS) and the effect of dam age, season, sex, and year of birth on the variance of these traits. In addition, the estimated heritability of these traits by estimating the (co)variance components was the second objective of this study. Data of 556 Dhofari breed calves from Salalah Livestock Research Station were used and statistically analyzed by SPSS, GLM, Duncan test and Linear Mixed model with restricted maximum likelihood (REML). Average of growth traits for birth weight (BW), weaning weight (WW), yearling weight (YW), pre-weaning daily gain (PRE), and post-weaning daily gain (POS) were 17.83 ±0.10, 85.11 ±0.60, 160.27 ±1.30 kg, 639.30 ±5.20, and 235.69 ±5.86 g/d respectively. Phenotypic Pearson correlation analysis of growth traits showed high significance (P 9 years old), season (spring), and sex (males) for all growth traits. Analysis of estimated variance components revealed heritability estimates for BW, WW, YW, PRE, and POS of 0.23 ±0.80, 0.41 ±0.86, 0.58 ±0.93, 0.40 ±0.85, and 0.59 ±0.92 respectively.