Hypophosphataemic rickets and nephrocalcinosis in ostrich chicks brooded and reared onlimestone sand

摘要

ON an ostrich farm in Victoria, Australia, over a four-year period between 1991 and 1995, many chicks developed swelling of the hock joint at six to 12 weeks old. Samples taken in 1995 were sent to the veterinary investigation facility at the Victorian Institute of Agricultural Science for examination. The swelling was localised to the proximal extremity of the tarsometatarsus. The birds became unthrifty and stunted with torsional and angular deformities of the tibiotarsal and tarsometatarsal bones;the most severely affected birds passed green urates and some died. The farm had one breeding pair of ostriches and hatched approximately 50 eggs per year. In the fourth (1995) breeding season 10 (20 per cent) of chicks were severely affected and died or had to be culled. A further 20 (40 per cent) could not be sold because of this skeletal problem.