A MspI PCR-RFLP within bovin growth hormone gene and its association with sperm quality traits in Iranian Holstein bulls

Abstract

The present study was aimed to examine the association of bovine growth hormone gene polymorphism with sperm quality traits including sperm volume (SV), sperm concentration (SPCO), total sperm (TS), fresh sperm motility (FSM), total fresh motile sperm (TFMS), post thaw sperm motility (PTSM), total post thaw motile sperm (TPTMS), total sperm dose (TSD) and testis biometry trait as average testis length (ATL), average testis width (ATW) and scrotum circumference (SC) in Iranian Holstein bulls. PCR-RFLP method with Msp-I restriction enzyme was used for genotyping. The frequency of the MspI(+)(C) and MspI(-)(D) alleles are 0.883 and 0.117, respectively. The genotype frequency for CC, CD and DD were 0.787, 0.191 and 0.022, respectively. The DD genotype was omitted of analysis. Mixed model analyses of sperm quality traits considering genotype and environment as fixed effects and animal as a random effect suggested that sire was a significant source of variation (P < 0.001) in all traits. The CC genotype resulted in a significant increase in SV (p = 0.022), FSM (p < 0.0001), TFMS (p < 0.0001), PTSM (p < 0.0001), TPTMS (p = 0.0067), TSD (p = 0.025) traits greater than CD genotype. However, CD genotype had significant effect on ATL (p = 0.0223) and ATW (p = 0.0544) traits, but not on SPCO (p = 0.3319), TS (p = 0.3818) and SC (p = 0.3841). These results indicate that new molecular markers associated with sperm quality traits can be used in marker-assisted selection in bulls.