Influence of dietary protein on blood cholesterol and related metabolites of growing calves.
Forty male, Holstein calves were utilized to evaluate effects of either low (12%) or high (25%) dietary protein on growth and serum metabolites, with a particular concern for serum cholesterol. All diets contained 19% acid detergent fiber and consisted of corn silage, alfalfa hay and grain mixtures. Average concentration of total serum cholesterol was depressed (P = .001) for calves on the high-protein diets (58.8 mg/dl) as compared with their low-protein counterparts (67.9 mg/dl). Calves fed the high-protein diet had lower (P = .002) free serum cholesterol but elevated high-density lipoprotein cholesterol as a percentage of total cholesterol. Calves receiving the high-protein diets showed increases (P = .206) in lecithin cholesterol acyltransferase activity compared with low-protein counterparts. Serum urea nitrogen was increased (P = .001) for calves fed high-protein diets, while serum protein and glucose remained unchanged. Calves fed the high-protein diets consumed less dry matter with improved (P = .09) growth efficiency (gain/feed).
D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle / Q000097:blood / Q000254:growth & development*; D002784:Cholesterol / Q000097:blood*; D008076:Cholesterol, HDL / Q000378:metabolism; D004044:Dietary Proteins / Q000378:metabolism*; D008055:Lipids / Q000097:blood; D008297:Male; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000378:metabolism
D008076:Cholesterol, HDL; D004044:Dietary Proteins; D008055:Lipids; D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase