Genetic studies on sheep performance.
Abstract: This study included data on 520 Ossimi and 629 Rahmani ewes, raised on experimental station belonging to the Ministry of Agriculture during the period 1970 - 1988.
The objectives of this study were to estimate non-genetic factors affecting,
heritability and genetic and phenotypic correlations of life-time lamb and wool production traits and mature weight using Harvey's Mixed Model Least-Squares and Maximum Likelihood computer Program (LSML 87).
Estimates of least squares means of total number of lambs born (TLB), total number of lambs weaned (TLW), total kilograms born (TKB), total kilograms weaned (TKW), total kilograms of fleece weight (TFWT) and mature weight (MWT) were 4.23, 3.73, 12.83, 46.98, 5.86 and 50.8 respectively, in Ossimi and 4.47, 3.74 13.81, 48.09, 6.55 and 53.3 ewes respectively in Rahmani ewes.
The differences between block-locations were highly significant in all studied traits in both Ossimi and Rahmani ewes. Age of dam and type of birth non significant effects traits in Ossimi and Rahmani ewes, while season of lambing significantly affected all studied traits in ossimi except TKW and MWT and non significantly affected all studied traits in Rahmani ewes.
The effect of weaning weight on all the studied traits in each ossimi and Rahmani ewes was not significant, while the effect of yearling weight was significant on all studied traits in ossimi ewes except TFWT, MWT and non significant on all studied traits in Rahmani ewes.
The estimates of heritability of the TLB, TLW, TKB, TKW, TFWT and MWT were.013, . 031, . 031, . 004, . 234 and. 121, respectively, in Ossimi ewes and.131,.154,.121,.142, negative and .268, respectively, in Rahmani ewes. The genetic correlations between these previous traits ranged from -3.104 to 1.3 in Ossimi and from -.102 to 1.1 in Rahmani, while the phenotypic correlations ranged from -.231 to.97 in ossimi and from -.029 to .96 in Rahmani.
Publication year 1991
Availability location مكتبة معهد بحوث الانتاج الحيوانى - شارع نادى الصيد - الدقى - الجيزة
Availability number 372
Organization Name
Country Egypt
Department Sheep and Goat Research Department
Author(s) from ARC
AGROVOC
TERMS		 Genetics. Genotypes. Performance testing. Phenotypes. Sheep.
Publication Type Master Thesis
↑