An analysis of leg abnormalities of boars in the Queensland performance testing station.

An analysis was made of the results of leg inspections of boars in the Queensland boar testing station at the start and end of their performance tests. The frequency among boars of 12 specific faults ranged from zero to 90% at the start and 7% to 73% and the end of testing. Of the 362 boars examined, 20% suffered from leg weakness. 11% of these had to be slaughtered and 9% recovered after return to the farm. The only faults significantly associated with leg weakness were: "up on toes" of the front feet and excessive flexion of the front knees ("over at knee"). The sire, breed and herd of origin of a boar had little effect on its having any one of the 12 faults. However, herds were found to differ in the total number of faults per boar and Large White had more front leg faults than Landrace. The correlation between number of leg faults and growth rate of a boar during test was + 0.12. Although lef weakness was an important cause of boar wastage, neither it nor leg faults were significant sources of error in evaluating the performance of boars which completed testing.