Study on Influence of Environmental Effect on Birth Weight, Weaning Weight and Daily Growth of Baluchi Sheep

Abstract

This study investigates different environmental effects on birth and weaning weight and daily growth of Baluchi lambs. For this purpose, we analyzed 10680 records that collection within a period of 21 years (1983-2003) in Abbasabad Sheep Breeding Station, located in northeast of Mashhad, Iran. Three different statistical models with considering effects of flock, litter size, sex, ewe age in parturition, lamb age in weaning weight and their interaction were used for parameters measurement. Except for effect of flock on weaning weight and daily growth, other effects were significant (p<0.01). For statistical analyses SAS software was used and coefficients of determination (R ) and coefficients of variance (CV) were estimated 2 0.47 and 12.88 for birth weight, 0.54 and 16.43 for weaning weight, 0.44 and 19.62 for daily growth, respectively. Male lambs in comparison with female lambs and single-born lambs in comparison with multiple-born lambs had higher birth weight and daily growth, however, effect of litter size on birth and weaning weights was higher in young ewes.