INFRARED THERMOGRAPHY OF PIGS WITH KNOWN GENOTYPES FOR STRESS SUSCEPTIBILITY IN RELATION TO PORK QUALITY

Abstract

Twenty five market-weight pigs averaging 92.0 kg body weight represented by eight halothane-negative with NN genotype, nine crossbred with Nn genotype and eight halothane-positive with nn genotype animals were thermographed to determine whether temperature differences were related to meat quality. Infrared thermograph analysis demonstrated no differences in mean external medial temperatures among genotypes in the live animal nor in the internal medial carcass surface. However, pigs with cooler mean side temperatures displayed a higher percent drip loss (P ≤ 0.09) and paler colored meat (P ≤ 0.03). This was particularly evident in the H+ pigs where a highly significant negative correlation between expressible juice (−0.87; P ≤ 0.01) as well as percent drip loss (−0.75; P ≤ 0.05) and mean live external medial surface temperature was observed. Furthermore, the halothane-positive pigs displayed small hot spots over the dorsal front shoulder area and over the posterior third of the animals. Key words: Infrared thermography, meat quality, pig genotype