Relationship between the Porcine Stress Syndrome gene and carcass and performance traits in F2 pigs resulting from divergent crosses

摘要

The PSS genotypes of 596 F2 pigs produced by initial mating of Brazilian native boars commercial sows and were characterized by PCR-RFLP and their carcass and performance traits were evaluated. Among the 596 animals analyzed, 493 (82.72%) were characterized as NN and 103 (17.28%) as Nn. With respect to carcass traits, Nn animals presented higher (p < 0.05) right half carcass weight, left half carcass weight, loin depth and loin eye area, and lower shoulder backfat thickness, backfat thickness between last and next to last but one lumbar vertebrae and backfat thickness after last rib at 6.5 cm from the midline compared to NN animals. Nn animals also showed (p < 0.05) higher values for most of the cut yields, indicating higher cutting yields for animals carrying the n allele and lower values for bacon depth, confirming lower fat deposition in carcass. In addition, Nn animals presented (p < 0.05) lower values for the performance trait weight at 105 days of age. These results indicate that animals carrying the PSS gene generate leaner carcasses, higher cut yields, and that the effects of the gene can be observed even in divergent crosses.