ARS | Publication request: MAPPING QTL FOR CARCASS COMPOSITION IN SWINE

Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: January 1, 1998
Publication Date: N/A

Technical Abstract: A backcross population of Meishan by White composite pigs was produced to identify QTL affecting growth, carcass composition and reproduction. Forty-one F1 females were produced by reciprocally mating Meishan and White composite pigs. F1 females were then mated to either Meishan or White composite boars to produce 2 parities. A genomic scan with markers at 20 cM intervals (n=156) was conducted across the entire population. Five hundred forty pigs were slaughtered at approximately 100 kg live weight and carcass measurements were recorded. Five measurements were collected for subcutaneous fat deposition (fat over the first, tenth and last ribs, over the last lumbar vertebra and average backfat), hot carcass weight, carcass length, loineye area, leaf fat and weight of untrimmed and trimmed wholesale products. Statistical analyses implemented a least-squares regression approach utilizing genotypic data for the entire chromosome. Each chromosome was analyzed separately. Fixed effects included in the model were contemporary group, sex and breed of sire. A covariate for hot carcass weight was fitted for analyses of all composition traits. Four genomic regions located on chromosomes 1, 4, 7 and X affected carcass traits at the genome wide level of significance of .05 (F-ratio > 9.3). Pleiotropic effects were detected for SSC1, 7 and X. These data did not detect QTL at previously identified regions for fat deposition on chromosomes 4 and 13 in a Wild boar by Large White population. Further studies need to be implemented to refine the location of the QTL and determine potential positional candidate genes.