Fig. 2From: Heat shock protein family D member 1 in boar spermatozoa is strongly related to the litter size of inseminated sowsCorrelation analysis between gene expression and pre-fertilisation parameters. A Linear regression of AVPR2 mRNA expression and litter size. B Linear regression of ACTB mRNA expression and litter size. C Linear regression of PHB mRNA expression and litter size. D Linear regression of HSPD1 mRNA expression and litter size. r, Pearson correlation coefficient; *P < 0.05, calculated via the linear regression testBack to article page