Effect of protein nutrition on bone strength and incidence of osteochondrosis in gilts

Leg-weakness in female breeding pigs has serious implications both in terms of economics and welfare, accounting for up to 0.2 of first litter gilt cullings at an estimated cost to the UK pig industry of up to £3.0 million (Douglas, 1992), with the principal predisposing cause in the growing pig being osteochondrosis. It has been reported that selection for increased lean tissue growth rate and increased growth rate accompanied by ad libitum feeding of diets with high energy and nutrient concentration may increase the incidence of osteochondrosis and leg- weakness (Jorgensen and Sorensen, 1998), although evidence is largely equivocal. The effect of protein level in the diet is uncertain. Although both high and low levels of dietary protein lead to bone growth failure and fracture in human studies ( Reid and New, 1997), protein level has not been found to affect osteochondrosis in pigs (Jorgensen, 1995), thus the aim of the current study was to assess further the effect of protein nutrition on leg weakness in gilts.