Molecular characterization of candidate genes for body weight traits in Awassi sheep breed

• Hero Tareq Omer1* Yousif Mohammad Salih Noori Al-Barzinji 1*

  Author

The objective of present study was to determine the genotypes of three loci (GH, CAST and MHC) that related to body weight traits in Awassi lambs. This experiment was conducted in commercial flock of Awassi sheep located at the Dhemat village –Erbil / Kurdistan region of Iraq. A total of 100, 92 and 87 lambs at birth, weaning and marketing age were used respectively, at lambing all relevant information were recorded and lambs were weighed at different ages.  Also a total of 87 Blood samples at marketing ages were collected from lamb’s for extracted the genomic DNA for each lamb, the purity and quantity of isolated DNA was measured using agarose electrophoresis and Nano Drop.

Most of Fixed effect have a significant effect on the lamb’s body weight. The BLUP as a breeding value for body weight at BW, WW and MW ranged from -1.839 to. 2.161, -12.162 to. 10.837 and -18.283 to. 18.316 kg/lambs, respectively. According to the BLUP value for body weight at MW the lambs ranged in three groups (high production 10%, replacement group 70% and low production group 20%). The lambs at high production group significantly give higher body weight than the lambs in low production group. The DNA concentration and DNA purity was calculated were ranged between (4.82-10.61) ng/ µl and (1.20-1.28), respectively.

The PCR-RFLP results show that the CAST, MHC and GH loci have polymorphism among lambs. The superior genotype for (GH, Cast and MHC) genes investigated in this study for body weight traits is CDBCCD recorded for lambs in high production group (55.33 ± 1.84 kg/lamb), while the genotype of lambs in low production group (33.41 ± 3.36 kg/lamb) is BECDBE. The high rang for body weight BLUP value of lambs and different allele with genotype for each locus means the selection can play major roles in speeding genetic improvement for body weight and increasing incomes for breeders.

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