Submitted to: Annual International Plant & Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 11/8/2013
Publication Date: 1/15/2014
Citation: Nonneman, D., Schneider, J.F., Wiedmann, R.T., Vallet, J.L., Rohrer, G.A. 2014. Dissection of two QTL on SSC2 identifies candidate genes for ovulation rate in swine [abstract]. Plant and Animal Genome XXII Conference Proceedings. Abstract #P596.
Technical Abstract: Litter size is an economically important trait to producers that is lowly heritable, observable only after considerable investment has been made in gilt development and responds slowly to selection. Ovulation rate, a component trait of litter size, is moderately heritable, sex limited and should respond favorably to genetic selection. A previous genome-wide association study identified over 100 QTL for ovulation rate with fifteen of the most significant regions accounting for about 48% of the total QTL variance. The objective of this study was to validate QTL and identify candidate SNP associated with ovulation rate on chromosome 2. Ovulation rate was collected on pubertal gilts and multiple parity Landrace-Duroc-Yorkshire sows at slaughter (n = 1720). Genotypes were collected using the Illumina PorcineSNP60 beadchip and Sequenom MassArray. Genotypes were analyzed for association using WOMBAT. Analyses of chip markers indicated that 2 QTL existed with estimated additive effects of -.53±.16 and .55±.15 (ALGA0016019 and ALGA0016191, respectively). Candidate genes in the chromosome 2 QTL regions known to be involved in folliculogenesis include ADAMTS19, ACSL6 and GDF9. SNP within ADAMTS19 and GDF9 were associated (P<0.05) with OR (n=920). While these genes are known to be involved in ovulation or associated with litter size in sheep or other species, they have not previously been associated with ovulation rate or litter size in pigs. The identification of genetic variation in candidate genes associated with ovulation rate should lead to a better understanding of their function and provide useful markers for selection for litter size.