Disorders of the Skeletal System in Poultry
Production characteristics of modern poultry lines (eg, body weight in broiler chickens, egg production in laying hens) place high demands on the skeletal system, and inadequacies in nutrition or husbandry often result in skeletal diseases. Skeletal disorders may be primarily infectious or noninfectious; both may be seen concurrently within a flock. Skeletal disorders cause lameness from biomechanical dysfunction and in broiler chickens result in poor growth, culled birds, increased mortality (caused by starvation and dehydration), and carcass condemnation and downgrading. Bone fractures in spent hens may be a welfare issue.
Before postmortem examination, flocks should be assessed. Live, lame birds should be examined and general flock health and management assessed. Serum samples may be collected for viral and mycoplasmal serology and/or biochemistry (eg, serum calcium). Gross pathology alone is often insufficient, and histopathology is usually necessary to reach a diagnosis. Bone ash measurement, feed nutritional analysis, and bacteriology are useful complementary investigations.