Influence of inbreeding on growth traits of Muzaffarnagari sheep

Abstract

A purebred flock of Muzaffamagari sheep, closed for about 24 years, was utilized to study the effector inbreeding on growth traits of lambs, Data on 4110 Muzaffamagari sheep for 24 years (1976 to 1990) were used to calculate inbreeding coefficient, The lamb traits considered in this study were birth, 3,6,9 and 12 month weights, average daily weight gain from birth until weaning and post-weaning average daily weight gain. Inbreeding coefficients ranged from 0 to 26%, The mean birth and 3 month weight of the outbred lambs were 3,19 and 14.99 kg and that of the inbred lambs 3.09 and 14.38 kg, respectively, the differences between the means being signifIcant. The mean 6-month birth weight of outbred lambs was 16.99 kg and that of the inbred lambs 16.56 kg, the difference betWeen the meanth not being significant. But 6-month weight among inbred groups were significantly different (15.35 to 17.45 kg). Increased inbreeding resulted in lesser lamb weights at birth, 3 and 6 months of age, Inbreeding evidently slowed the weight af birth, 3 and 6 months but did not influence body weight at 9 and 12 months of age. Inbreeding not only resulted in lighter lambs at birth, 3 and 6 months Weight but it slowed gains at pre-weaning age.