The pathology of deep pectoral myopathy of turkeys

The gross and microscopic pathology of deep pectoral myopathy was studied in 35 turkey breeder hens. In this disease the lesions, consisting of strictly focal ischaemic necrosis, were confined entirely to the supra-coracoid (deep pectoral) muscles of one or both sides. Vascular lesions consisting of thrombosis, intimal proliferation and aneurysm formation were located in, and immediately around, the necrotic muscle tissue. Although this peripheral vascular disease would perhaps be sufficient to account for the focal ischaemic necrosis, we have no evidence at present to prove its primary involvement. Furthermore other factors such as stress or trauma may play a contributory part in the development of this condition.