Evaluation of the Duroc in comparison with the Landrace and Large White as a terminal sire of crossbred pigs slaughtered at 85 kg liveweight

Abstract

A study was undertaken to evaluate the Duroc as a terminal sire in a three-way cross compared to a two-way backcross with the Landrace and Large White breeds. It comprised an analysis of litter records from seven farms and growth and carcass measurement data collected on three farms, along with the production ofDuroc andLandracecrossbreds at a central location and their comparative evaluation in three feeding trials. On the farms, Duroc-sired litters had relatively fewer stillbirths but breed of sire did not influence the number oflive births in the litter nor litter size at weaning. Duroc crossbreds reached slaughter weight 7-10 days earlier than Landrace or Large White crosses, had higher carcass yields (0.4 kg), and lower backfat measurements (1-3mm). In the centrally conducted trials, breed of sire did not influence litter size or piglet bodyweight at birth or at 3 weeks of age. On a restricted and a fIxed feed/fixed time feeding regimen, Duroc crossbreds reached slaughter weight earlier than Landrace crossbreds, utilised their feed more effIciently, had higher carcass yields, and had reduced backfat measurements. Breed-of-sire effects in the same direction were found with ad libitum feeding but the differences were smaller and only those in growth rate and killing-out percentage were statistically significant. Overall, the breed differences were considered to be of sufficient magnitude to warrant greater use of the Duroc breed in commercial production systems and to warrant further comparative research with more sires and farms.

Keywords:

• crossbreeding
• Duroc
• Landrace
• Large White
• feeding regimen
• carcass measurements
• intramuscular fat
• pigs