Effect of tibial dyschondroplasia on carcase part weights and bone characteristics.

1. The effect in broilers of tibial dyschondroplasia (TD) on carcase part weights and bone characteristics was investigated by studying the progeny of 10 sires and 40 dams. The correlations between TD and bone variables were also estimated. 2. The incidence of TD was 59% at 42 d of age. There were no significant differences in slaughter weight of birds with and without TD. However, in females, breast weight was heavier in affected birds. Neck plus back weight of birds with TD was significantly heavier than in birds without TD. 3. Breast blister frequency of birds was independent of the presence of TD. 4. Birds with TD had longer bones than birds without TD. However, TD had no effect on tibiotarsus weight, width, ratio of tibiotarsal to body weight and ash. A negative correlation was observed between TD score and bone ash percentage.