Severity of atherosclerosis in parrots in relation to the intake of alpha-linolenic acid.

Abstract

Atherosclerosis is a common disease among parrots, but little is known about possible risk factors. Important risk factors in humans are an elevated plasma cholesterol concentration and increased platelet aggregation; high intakes of polyunsaturated fatty acids have beneficial effects. In this study, we tried to establish a relationship, if any, between dietary fatty acids and the severity of atherosclerosis in parrots. We collected dead parrots and scored the degree of atherosclerosis in the beginning of the aorta and the brachiocephalic arteries. It was not possible to assess the intake of fatty acids with food questionnaires so fatty acid composition of adipose tissue and breast muscle had to be used as an index of the dietary fatty acid composition. In all, 202 birds were collected. Gender was not related with atherosclerosis, but the degree of atherosclerosis increased with age and among the various species; African grey parrots appeared to be the most susceptible. The contents of linoleic acid in breast muscle or adipose tissue were not associated with the severity of atherosclerosis. For the relative percentage of alpha-linolenic acid in either breast muscle (P = 0.09; n = 175) or adipose tissue (P = 0.056; n = 21), a borderline significant relation with the degree of atherosclerosis was found. Parrots without atherosclerosis had significantly higher levels of alpha-linolenic acid than did the other animals. On the basis of these data, we suggest tentatively that a high dietary intake of alpha-linolenic acid protects against the development of atherosclerosis in parrots.