Study on IL8RB gene expression in crossbreeding program of Guilan Native cow

IL8RB gene is one of the chemokine receptors presented on neutrophil surfaces whichare necessary for maximizing of neutrophils ability during infection. Different sequence and expression of IL8RB gene lead to different resistance to mastitis in cow populations. The aim of current study was to investigate expression changes of IL8RB gene resulted from crossbreeding of Guilan Native cows with Holstein cows. We collect 56 blood samples from 5 different cow populations in Guilan Native cattle breeding center. After RNA extraction and cDNA synthesis, realtime PCR reactions were performed in all samples with three repeats for each sample. We used GAPDH and RPLP0 as internal reference control genes. The maximum amount of IL8RB gene (0.74±0.77)average normalized expression was in Native cow populations and the minimum expression (0.12±0.22) was in 75 percent Holstein crossbred cow populations. Highest to lowest amount of IL8RB gene average normalized expression was in Native cow (0.74±0.77), 50 percent sire Native and dam Holstein crossbred cow (0.3±0.27), 50 percent sire Holstein and dam Native crossbred cow (0.26±0.3), Holstein cow (0.23±0.26), and 75 percent Holstein crossbred cow (0.12±0.22), respectively. With Consideration of highest gene expression in Native cow and decreasing in gene expression respect to increasing in blood contribution of Holstein cow which they are sensitive to mastitis, consequently changes in gene expression of IL8RB are related to resistance to mastitis. As this study showed the effect of crossbreeding on IL8RB gene expression changes, then it is necessary to consider the consequences of crossbreeding on native cattle breeding program.