Avulsion of the patellar ligament in osteopenic laying fowl
Randall, C.J.; Duff, S.R.
Veterinary Record 123(17): 439-441
1988
ISSN/ISBN: 0042-4900 PMID: 3201683 Document Number: 311753
Metabolic bone disease in caged laying fowl has been associated with mortality and decreases in egg production (caged-layer fatigue). Recently there appears to have been an increasing incidence of the disease and the affected flocks have shown a variable response to dietary treatments. In 14 birds from eight recent submissions, avulsion of the patellar ligament together with part of its bony insertion was observed. Because the skeletons of the affected birds were judged from radiographs to be osteopenic, the lesions were probably pathological fractures. Histopathological studies of four birds revealed osteoporosis affecting cancellous bone trabeculae; in one bird, however, the medullary bone trabeculae were largely composed of unmineralised or poorly mineralised matrix, a finding which can be interpreted as osteomalacia.