A within-litter comparison of the three halothane genotypes. 2. Performance, carcass quality, organ development and long-term effects of transportation and amperozide

Abstract

The aim of the investigation was: (1) to compare the three Hal genotypes with respect to performance, carcass quality and organ development at slaughter, (2) to study long-lasting effects of transportation and treatment with amperozide. The study comprised 120 (23 NN, 69 Nn and 28 nn) crossbred pigs, offspring of heterozygous boars and sows. The Hal genotype was revealed by combining the halothane test and blood typing. At an average age of 12 weeks, the pigs were subjected to one of four treatments (with and without transport × with and without amperozide treatment). The pigs were kept in groups of four pigs ( 1 NN, 2 Nn and 1 nn) originating from different litters and were fed individually. Four nn pigs died during the experiment, one owing to fighting on the first day and three on the way to the slaughter house. The nn pigs had higher daily weight gain and lower feed to gain ratio than the NN and Nn animals. Carcass lean content was higher, but meat colour paler for the nn compared with the NN and Nn pigs. The heterozygotes were intermediate to the homozygotes for carcass lean content and meat colour. Organ weights were lower for the nn compared with the NN animals, and those of the Nn pigs were intermediate or close to the NN animals. Pigs subjected to a 5-h transport at 12 weeks had lower carcass lean content than non-transported ones. Amperozide treatment at the same age resulted in increased crude fat content of the liver at slaughter 3 months later. Adrenal weight at slaughter was higher for the amperozide-treated but nontransported animals compared with the other three treatment groups.