Towards a better understanding of the genetics of lean meat growth – from UNE20P to UNE23P

The aim of this project was to optimise selection indices for efficient lean meat growth. Traditionally, genetic improvement of lean meat growth and feed efficiency has been based on ad libitum feeding. However, selection for lean meat growth and feed conversion ratio under ad libitum feeding has led to a reduction in feed intake in modern genotypes to the extent that feed intake is often not sufficient to meet the animal’s requirement for maximum protein deposition. Results from selection experiments have indicated that it might be beneficial to select pigs under restricted feeding for efficient lean meat growth (McPhee et al., 1988; Cameron and Curran, 1995). These selection experiments were conducted under research conditions where pigs were single penned and feed intake of the individual pig was well monitored. However, in commercial conditions pigs are group penned and in order to record feed intake in these commercial conditions electronic feeders have to be used.