Life span is shortened in BHE/cdb rats fed a diet containing 9% menhaden oil and 1% corn oil.

The effects of feeding 2 or 10% fat on glucose tolerance, blood lipids, life span and tissue pathology of male BHE/cdb rats were studied. Six groups of 30 rats were fed from weaning diets containing 1% corn oil plus either 1 or 9% corn oil (CO diets). Animals that became ill and died were necropsied and their tissues were examined histologically. Glucose tolerance and blood lipids were determined at 300 and 600 d of age. At 300, 500, 600 and 700 d of age subsets of rats were killed and heart, aorta, lungs, liver, pancreas and kidneys collected for histological examination. The experiment was terminated at 700 d. Feeding the high level MO or BT diet delayed the development of glucose intolerance and lipemia. Longevity was shorter in the rats fed the high MO diet. There were few differences among the groups of rats fed the 2% fat diets with respect to glucose tolerance and lipemia. Glomerulosclerosis was observed in all rats but was more severe and appeared earlier in rats fed the high MO diet than in those fed the high CO or BT diets. In rats with severe renal lesions, mineralized foci were observed in soft tissue, notably the aorta and heart. The results of this study indicate that the source and amount of the dietary fat can influence age-related tissue changes and longevity.