Effect of obesity per se on plasma lipid and aortic responses to diet in swine.
Thirty-two genetically lean and obese Yorkshire X Duroc crossbred castrated male pigs were divided within genetic line into two groups at 7 weeks of age. Eight pigs within each line were fed a diet low in fat and cholesterol (maize-soybean meal diet fortified with minerals and vitamins). The other group was fed a similar diet containing added beef tallow (11%) and dried egg yolk (1%). All pigs were fed ad libitum for 4 months when one-half of each group was slaughtered. All other pigs were continued on their respective diets at a restricted level of intake for an additional 5 months at which time the protein source of two pigs in each diet group within each genetic line was changed from soybean meal to casein. After an additional 6 months on their respective diets (16 months total duration of experiment) these pigs were slaughtered. Blood samples were taken monthly or bimonthly for total plasma cholesterol and triglycerides. At slaughter, the aorta was opened, stained with Sudan IV, and the stained area traced and measured planimetrically. Only a moderate rise occurred in plasma cholesterol and triglycerides of pigs fed high fat-high cholesterol diets. Genetically obese pigs were no more susceptible to diet-induced hypercholesterolemia and to the percentage of the surface area of the aorta stained with Sudan IV than were lean pigs. It is concluded that obesity per se is not necessarily associated with development of atherosclerosis in pigs and that innate ability to metabolize high dietary cholesterol is of greater importance than body fatness in determining the response to diet.
D000818:Animals; D001011:Aorta / Q000473:pathology; D001161:Arteriosclerosis / Q000209:etiology*; D002784:Cholesterol / Q000097:blood; D004036:Diet, Atherogenic; D008055:Lipids / Q000097:blood*; D008297:Male; D009765:Obesity / Q000097:blood / Q000150:complications* / Q000473:pathology; D013552:Swine; D014280:Triglycerides / Q000097:blood
D008055:Lipids; D014280:Triglycerides; D002784:Cholesterol