Associations between osteochondrosis and conformation and locomotive characteristics in pigs

Conformation and locomotive characteristics (CLC), i.e., leg conformation and gait movement patterns, may be associated with osteochondrosis (OC) in pigs. Osteochondrosis and CLC increase the risk of premature culling. This study investigated whether CLC have an explanatory value, over the previously modelled effects of sex, feeding, and housing conditions, on the occurrence and severity of OC in several joints and at the animal level. At 154 to 156 d of age, 267 pigs were subjectively scored on 9 conformation and 2 locomotive characteristics. Scoring was performed on a 9-point linear grading scale. For conformation characteristics, score 5 indicated normal conformation and scores 1 and 9 indicated severe deviations from normal. For the locomotive characteristics, score 1 indicated normal locomotion and score 9 indicated severe deviation from normal. At 161 to 176 d of age, pigs were slaughtered and joints were dissected for macroscopic evaluation of OC status. Results showed that swaying hindquarters and a stiffer gait were associated with higher scores for OC in, respectively, the femoropatellar (P = 0.018) and tarsocrural joint (P = 0.005); smaller inner claws as compared to the outer claws of the front legs was associated with lower scores for OC than equally sized claws in the femoropatellar joint (P = 0.021) and on animal level (P = 0.010); steep and weak pasterns of the front legs were associated with higher scores for OC in the elbow joint (P = 0.004) and on animal level (P = 0.018); X-shaped hind legs was associated with higher scores for OC on animal level (P = 0.037); and steep and weak pasterns of the hind legs were associated with lower scores for OC than normal conformation in the tarsocrural joint (P = 0.05). This study found several CLC that were associated with OC in several joints and at an animal level. This study showed that certain CLC might be used as indicators of OC and included in the criteria for selection of replacement animals for the breeding herd.