Histological evaluation of the vascular system for the severity of atherosclerosis in hyper and hypotensive male and female turkeys: comparison between young and aged turkeys.

Relationships among age, blood pressure, and atherosclerosis were studied in turkeys genetically selected for high and low systolic blood pressure ranging in age from 2 days to 104 weeks. Relationships between sex and atherosclerosis were studied only at 104 weeks of age. Abdominal aortas were examined in all birds in each age group. The left and right internal, external, and common carotid arteries, cranial and caudal thoracic aortas, area of coeliac orifice, sciatic junction, left and right sciatic arteries, left and right coronary arteries, and left and right deep branches of the coronary arteries were examined in the 104-week-old group. Mean abdominal aortic plaque scores for the different age groups increased linearly to the age of 12 weeks; after this time scores reached a plateau. Except for the first and last time period, the hypertensive group of males showed a significantly greater abdominal aortic plaque score than the hypotensive group. The right sciatic artery was the only other blood vessel in the 104-week-old group that had a significantly greater plaque score in the hypertensive line when compared with the hypotensive line. In the 104-week period, only the left and right sciatic arteries showed significantly higher plaque scores in the males than in the females. Also, only the male turkeys showed an increase in plaque scores with a concomitant rise in systolic pressure. In 104-week-old females there was no evidence of intimal change in either the left and right internal carotids, left and right common carotids, cranial thoracic aorta, or the right coronary artery. The hypertensive line had significantly greater blood pressure and greater ventricular weight, length, and sagittal width than the hypotensive line. The 104-week-old turkeys had more lipid staining material within the plaque than the younger birds, and calcification was evident in two of the older turkeys.