Genotype, sex and interaction effect on lamb growth traits

Abstract

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 (lt) 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 (lt) 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.

Metode odgajivanja imaju važnu ulogu u ovčarskoj proizvodnji. Od suštinskog značaja u proizvodnji mesa ovaca je održavanje genetske raznovrsnosti i varijabilnosti populacija. Cilj ovih istraživanja je da se utvrdi uticaj genotipa i pola, kao i njihovih interakcija na osobine porasta jagnjadi. Rezultati studije pokazali su da muški pol svih genotipova je dominantan u pogledu mase tela u svim uzrastima (od BWB do BW90). Najveća telesna masa (BWB) bila je kod muških grla genotipa 2 (W). Najnižu telesnu masu na rođenju, imala su ženska jagnjad genotipa 1. Masa tela pri uzrastu od 30, 60 i 90 dana, kod oba pola je bila dominantna kod genotipa 4 (PxWxF). Genotip 1 (P)- oba pola, imao je najniže vrednosti masa u svim uzrastima (BWB, BW30, BW60, BW90). Rezultati istraživanja su pokazali bolju efikasnost rasta kod muških u odnosu sa ženska grla. Rezultati fiksnih faktora i njihovog uticaju na telesnu masu jagnjadi pokazali su veoma značajan efekat genotipa (P (lt) 0,01) pri rođenju (BWB), kod uzrasta 30, 60 i 90 dana (BW30, BW60, BW90). Pol je imao visoko značajne efekte (P (lt) 0,001) kod svih uzrasta. Interakcija između genotipa i pola pokazala je veoma značajan efekat (P≤0.01) na telesnu masu pri rođenju (BWB), ali dobijene vrednosti razlika nisu bile značajne (P≥0.05) u dobi BW30, BW60 i BW90. Superiornost genotipa 4 (PxWxF) pokazala se u uzrastu od 30, 60 i 90 dana, što može biti izazov i praktična korist za farmere koji koriste ukrštanje.