Evaluation of growth traits in Muzaffarnagari sheep reared under semi intensive feeding management

Abstract

Data on 2845 Muzaffarnagari lambs born during 2001-2015 at ICAR-Central Institute for Research on Goats, Makhdoom, Farah, Mathura were recorded to study growth traits in terms of body weights and average daily weight gains at various age stages. The overall least squares means for body weights at birth, 3, 6, 9 and 12 months age were 3.46±0.06, 16.11±0.37, 24.13±0.32, 28.49±0.28 and 32.68±0.27 kg and average daily gains (ADGs) during 0–3, 3-6, 6-9, 9-12 and 3-12 months age groups were 137.59±4.14, 88.49±3.57, 56.47±3.07,

55.57±2.93 and 65.12±1.68 g, respectively. Sex, season and period of lambing had highly significant (P<0.01) influence on all the body weights and average daily weight gains while parity of dam showed highly significant influence on birth weight, 3 month weight, ADG during 0-3 & 3-12 months and type of birth of lamb had similar effect on birth, 3 and 6 month weights and ADG during 0-3 and 3-6 month age intervals. Male lambs gained higher weights and ADGs than female lambs at all the growth stages while, period of lambing did not show any definite trend. Comparison of body weights and ADGs of single and twin lambs indicated that lambs born as single had higher birth and 3 month weights and ADG (0-3M) and thereafter twins showed higher body weights as well as ADGs at subsequent age stages. Dams' weight at lambing showed highly significant influence on birth and 3 month body weight and preceding weights had highly significant effect on their subsequent body weights. Maximum growth of lambs was recorded during 0-3 month (pre-weaning) age followed by 3-6, 6-9 and 9-12 age groups. This period of growth may be considered very crucial and should be ensured with proper management, feeding and health care for better productivity and outcome.