Association of DIO2 gene polymorphism with some productive traits and prolificacy in local Awassi sheep

الملخص EN

In this study 40 ewes of native Awassi breed and their offspring of 46 birth which belong to Department of Animal Production/College of Agriculture / University of Baghdad for the period of January 2018 to July 2018.

The aim of the study was to determine the polymorphism distribution and allele frequency of DIO2 (exon 2) gene and its relationship with the productive traits and prolificacy.

In PCR analysis, specific primer was used to amplify 350bp fragment flanking the polymorphism site Restriction fragment length Polymorphism (RFLP) applied on PCR Product by using (BstNI) restriction enzyme and genetic varied manifestations (Polymorphism) to the target area of the gene encoding DIO2 (exon 2) depending on the different enzymatic digestion resulting, CC wild, CG and GG, it amounted to distribute genetic manifestations of gene DIO2 ratios in a sample sheep Awassi thoughtful 82.50, 12.50 and 5.00% for each of the genotypes and it was the contrast between these highly significant proportions (P<0.01), allele frequency were 0.89 and 0.11 of each allele, G and C respectively.

Total milk production significantly affected(P˂0.05) by DIO2 gene polymorphism, the highest production was in ewes with CG genotype (82.20± 4.21 kg), but non-significant effect in lactation period.

Percentage of milk contents, fat, protein and sold non-fat affected by this DIO2 gene polymorphism (P˂0.05), and non significant in milk lactose percentage.

Effect of genotype of LPR gene in prolificacy average was significant (P<0.05) for the Awaasi sheep that had the CG (1.20 ± 0.05 lamb/ewe) and CC (1.15 ± 0.06 lamb/ewe) genotype in this study.

Concluded through the study of the genotype of DIO2 gene and its future it adoption to set the genetic rehabilitation strategies for sheep to maximize the economic return of farmed elect and crossing genotypes that have achieved the milk production and best prolificacy projects.