S. J. Moeller*, T. J. Baas, T. Leeds, R. S. Emnett, and K. M. Irvin. The Ohio State University, Columbus, OH, 43210 USA.
One hundred eighteen progeny from the mating of 15 purebred Hampshire sires to Yorkshire x Landrace F1 females were genotyped for the Rendement Napole (RN) gene to study the impact of the RN- mutation on pig performance and quality of pork. Thirty-seven of 118 progeny were classified normal (rn+,rn+) and the remaining 81 carriers (RN-/rn+). Sire genotype estimates classified two sires as rn+,rn, two sires RN-/RN-, and eleven sires RN-/rn+. No differences between RN-/rn+ and rn+,rn+ genotypes were observed for growth rate, loin muscle area or backfat at the tenth and last rib locations. RN-,rn+ loins were significantly paler in color, with lower ultimate pH, higher drip loss, and more purge and cooking loss. Sensory and mechanical tenderness measures were not different among genotypes. Intramuscular fat level was lower but juiciness score was higher in loins from the RN-/rn+ genotype pigs.