Spontaneous coronary arteriolosclerosis in broiler chickens

Arteriolosclerotic changes were found in 202 out of 203 randomly collected heart specimens of broiler chickens. These chickens were reared in a poultry farm and killed at a poultry meat processing plant at 60 days of age with healthy appearance. Cellular intimal thickening due to a proliferation of smooth muscle cells of small arteries or arterioles were found mostly in the innermost layer of the left ventricle. Severity of the thickening varied from slight to severe. In 2 cases, myocardial necrotic changes were found in the proximity of severely affected small arteries and arterioles.