Genotype, sex and interaction effect on lamb growth traits

The pure breeds and crossing have an important role in production. It is essential in sheep meat production to maintain the genetic diversity of the adapted breeds, pure breeds and their crosses. Objective of the study is to determine the impact of genotype and sex on growth traits of lambs. Results of the study showed that male of all genotypes were dominant on body weight in all ages (from BWB to BW90). The highest birth weight (BWB) got male of genotype 2 (W). The lowest body weight at birth was the female lambs of genotype 1 (P). Body weights at ages 30, 60 and 90 days, male and female of genotype 4 (PxWxF) were dominant among other genotypes. Genotype 1 (P) of both sexes had the lowest bodyweights in all ages (BWB, BW30, BW60, BW90). The result showed better growth efficiency from males compared with females. The results of fixed factors and its impact on body weights of lambs showed very significant effect of genotype (P<0.01) on body weights of lambs at birth (BWB), ages 30, 60 and 90 days (BW30, BW60, BW90). The effect of sex had highly significant effects (P<0.001) on all ages. The interaction between genotype x sex showed a very significant effect (P≤0.01) on body weight at birth (BWB) but were not significant (P≥0.05) on body weights of lambs at ages BW30, BW60 and BW90. Superiority on growth traits of genotype 4 (PxWxF) at ages 30, 60 and 90 days, indicating that three-bred crossing resulted in high growth traits. [Projekat Ministarstva nauke Republike Srbije, br. TR 31053]