Abstract #769

# 769
Genetic analysis and whole-genome wide association for feeding behavior traits in Duroc pigs.
Shihui Jiao*1, Christian Maltecca1, Yijian Huang2, Kent A. Gray2, 1North Carolina State University, Raleigh, NC, 2Smithfield Premium Genetics, Rose Hill, NC.

This study was aimed at estimating genetic parameters for feeding behavior and production traits and identifying genomic regions influencing those behavior traits in a Duroc population. Feed intake and related measures were collected from 2004 to 2013 for 14,869 boars with 4,940,348 visits. Several 7,319 pigs were genotyped with 35,700 SNP available for analysis. Traits included 4 production traits; average daily feed intake, average daily gain, off-test body weight and backfat thickness and 12 feeding behavior traits include; daily occupation time (OTD), number of visits (NVD), feeding rate (DFR), feed intake per visit (FIV), occupation time per visit (OTV), standard deviation (SD) of feed intake per visit (ASDFIV), SD of occupation time per visit (ASDOTV), SD of feeding rate per visit (ASDFRV), SD of daily feed intake (SDFI), SD of daily occupation time (SOTD), SD of number of visits (SDNVD) and SD of feeding rate (SDFR). Except for SDFI and SDFR, all behavior traits were moderately heritable with estimates ranging from 0.32 ± 0.03 (SOTD) to 0.68 ± 0.03 (FIV). Genomic heritability estimates using single-step methods incorporating genotypes were slightly lower than those obtained using pedigree by 0.10 ± 0.09 averaged across all behavior traits. Genetic correlation of behavior traits with production traits varied (ranging from −0.481 to 0.618). Single trait association analyses for behavior traits for 1,541 boars were performed using mixed linear models. Significance of marker was declared with a p-value less than 1.40 × 10−6 (Bonferroni correction). A total of 35 significant markers on SSC 2, 7, 8, 9 and 18 associated with NVD, OTV, ASDFRV and SOTD were identified and putative genes included NCR3 (involving in natural killer cell mediated cytotoxicity and associated with obesity in human), CLPS (activating in digestion of dietary lipid and absorption) and PPARD (regulator of lipid metabolism). In conclusion, feeding behaviors were moderately heritable and we have identified several genomic regions associated with traits affecting feeding behaviors that may help us understand the genetic mechanism controlling the traits.

Key Words: genomics, feeding behavior