Comparative efficiency of clinical and post-mortem examination for detection of tibial dyschondroplasia in broiler breeding

Abstract An investigation of leg abnormalities, including dyschondroplasia, was conducted in 45-day-old male elite breeders. The birds were reared by a broiler breeder company under standard commercial broiler conditions and at 45 days of age a random selection of male progeny from 10 sires were examined clinically, according to a commercial procedure, before being killed by cervical dislocation. Detailed post-mortem examination of the legs included inspection of the growth plates and scoring of lesions of dyschondroplasia. Differences in the prevalence of dyschrondroplasia were recorded between sires, dams within sires and sires of dams. A total of 557 birds were examined, representing at least 50 birds per sire. Lesions of dyschondroplasia were detected in 26.9% of the birds, the site of highest prevalence being the proximal tibiotarsus. There was a highly significant difference in prevalence between sire families ( P P P P A simple dissection method for assessing lesions of dyschondroplasia and some other aids to its detection are described. The observed association between various forms of leg abnormalities are briefly discussed.