Chronic osteoarthritis in a captive mountain lion (Felis concolor)

Resumo

A 23-year-old male Mountain Lion (Felis concolor) died after developing chronic lameness in the Zoological Park “El Pinar”, Caracas-Venezuela. Were practice euthanasia. Grossly, the radio-ulnar- humeral joint had severe bilateral lesions on the surface of the articular cartilage, with erosion of the cartilage and exposure of subcondral bone. There was approximately 1 ml of synovial fluid that was yellowish, and had a decreased viscosity. Histopathology revealed severe erosion and ulceration of the articular cartilage, with variable degrees of exposure of the subcondral bone. Bone tissue had defective osteoid matrix formation, and mineralization failure, resulting in loss of bone lamellae. Radiographic changes included decreased cortical density, trabecular growth pattern, fractures and microfractures. Failure in the formation of bone callus, and presence of osteophytes. These reports support the osteoarthritis and degenerative disease joint under conditions of captivity in a mountain lion.