The influence of weaning regime on central testing station performance in pigs

Abstract
To investigate possible pre-test environmental effects on testing station performance, pigs from a total of 107 litters from two breed types were weaned on one of three treatments: weaning at 3, 5 or 8 weeks of age, with a different creep-feeding regime on each. At 8 to 10 weeks of age, litter groups (usually consisting of two boars, one male castrate and one gilt) were sent to a Meat and Livestock Commission testing station and performance-tested from 27 to 85 kg live weight on twice daily to-appetite feeding.Weaning treatment significantly affected live weight at 50 days and boar growth rate and feed efficiency on test, but carcass traits were largely unaffected. Boars weaned on the 8-week treatment showed a significant advantage in index score of two-thirds of a standard deviation over those weaned at 3 weeks. A smaller number on the 5-week treatment were intermediate but did not differ significantly from those on the other two. It is concluded that wide variation in the weaning methods of herds sending pigs to a testing station could affect selection decisions. Ways of removing any bias by standardizing weaning methods or by statistical adjustment are discussed.