Fecundity Booroola Gene (FecB) Polymorphism in some Indigenous Sheep Breeds in Iraq

Although the human population of Iraq is increasing with increasing demands on meat and milk, the Iraqi sheep population is decreasing year by year. Local sheep breeds exhibit a low twin rate and fecundity, resulting in a low heritability value. Previous studies showed that FecB is one of the candidate genes related to fecundity in sheep, in this gene cause an increase in ovulation rate and litter size. The aim of this study was to identify a single nucleotide polymorphism (SNP) in the FecB gene in the Karadi and Awassi sheep breeds. 50 blood samples were collected from both breeds to extract the genomic DNA. A 140-bp DNA fragment of FecB gene was successfully amplified, and the PCR product was sequenced and compared. The DNA sequencing ofhe FecB gene in Karadi and Awassi sheep compared with NCBI blast. The results revealed no single nucleotide polymorphism (SNP) was found in Karadi and Awassi sheep breeds, this can explain the low level of litter size and low fecundity of these breeds. More studies on other genes related to fecundity are needed to get more potential genetic background about these indigenous breeds. In conclusion, the absence of polymorphism in the 140-bp and pattern could be the reason for low litter size and ovulation rate in these local breeds, since the absence polymorphism is significantly correlated with low litter size and ovulation rate. Further studies should be made to show the required crossbreeding between our local breeds with foreign breeds that carry the favorite genotypes of this gene which will lead to an increasein the expression of this gene in the local Iraqi sheep breeds without effect on the acclimatization traits of these breeds to the environmental conditions in Iraq.