Effect of the estrogen receptor (ESR) and ryanodine receptor (RYR1) genes on reproductive traits of Slovak Large White, White Meaty and Landrace pigs (short communication)

We investigated the effect of the estrogen receptor (ESR) and ryanodine receptor (RYR1) genes on total number of born (TNB), number of born alive (NBA) and number of weaned (NW) piglets in Large White (LW), White Meaty (WM) and Landrace (L) sows from six Slovak breeding farms. We found a significant effect of ESR locus on NW (P <= 0.01) in LW, however, we observed a negative effect of BB genotype on the trait. In WM, positive associations of B allele with TNB, NBA, NW were found but the differences were not confirmed statistically. A highly significant effect (P <= 0.01) of ESR locus on TNB (+0.62 +/- 0.18 pigs per copy of B allele), NBA (+0.65 +/- 0.18) and NW (+0.51 +/- 0.16) was identified in L breed. With RYR1 gene we found significantly higher TNB and NBA in heterozygous WM sows (+1.01 +/- 0.36 in TNB; +0.87 +/- 0.32 in NBA; P <= 0.01). NBA was also significant in LW (+0.41 +/- 0.19; P <= 0.05).