The Effect of Non-Genetic Factors on Relative Growth Rate of Sonadi Sheep at Different Ages

The present study was conducted to assess the effect of non-genetic factors on relative growth rate of Sonadi sheep of different age groups. In this study data on 1396 Sonadi sheep maintained over the period of 2012-2019 under the Mega Sheep Seed Project, College of Veterinary and animal Science, Navania, Vallabhnagar, Rajasthan were analysed to assess the effect of non-genetic factors (year of birth, season of birth, sex, type of lamb) on relative growth rate viz. 0-3, 3-6, 6-9 and 9-12 months age groups. The overall least-squares mean along with standard error for RGR1 (0-3M), RGR2 (3-6M), RGR3 (6-9M) and RGR4 (9-12M) were 1.32±0.03, 0.42±0.02, 0.226±0.19 and 0.277±0.02 Percent per day, respectively. Year of birth had highly significant (P≤0.01) for RGR1, RGR2 and RGR4 group while significant (P≤0.05) effect on RGR3 group. Effect of season of birth on relative growth rate was also highly significant (P≤0.01) for RGR1 and RGR2 group while significant for RGR3 and RGR4 groups. Sex of lamb showed significant (P≤0.05) effect on RGR1 and RGR2 while non-significant on rest of the groups (RGR3, RGR4) whereas effect of type of birth on relative growth rate was found to be non-significant on all groups. The assessment of non-genetic factors plays an important role to formulate effective breeding programme for improvement of growth performance.