Causes of and predisposing risk factors for leg disorders in growing-finishing pigs.

Abstract This review provides an overview of common causes of leg disorders in growing-finishing pigs (30-100 kg) reared in intensive production systems. We define three overall cause categories of leg disorders in finishers: (1) infectious arthritis caused by Mycoplasma hyosynoviae , Erysipelothrix rhusiopathiae , Haemophilus parasuis and Streptococcus suis , (2) physical injuries such as fractures of the leg and lesions to the claw and (3) osteochondrosis. Different predisposing risk factors at herd and animal level are important with regard to the occurrence of leg disorders. The construction of the pen, the floor type and the supply of straw are of primary importance for the occurrence of physical leg disorders, while anatomic characteristics, the growth rate and the feeding strategy can affect the risk of osteochondrosis. Exposing the individual pig to a stressful environment (such as mixing pigs from several herds) may alter the immune status, and hence, predispose to infectious arthritis. The review summarizes and quantifies (where possible) the effect of important predisposing risk factors for leg disorders in growing-finishing pigs.