Reduction of the Cholesterol Content of Eggs by the Oral Administration of Lovastatin to Laying Hens

Two experiments were conducted in which laying hens were administered lovastatin, a competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the rate-limiting enzyme of the cholesterol biosynthetic pathway. In the first study, 26-week-old White Leghorn hens were fed corn-soybean meal diets containing either 0, 0.0059, 0.0124, or 0.0265% lovastatin (analyzed values) for a period of 35 days. Cholesterol content per gram of yolk was significantly lowered with each successive level of lovastatin, whereas egg cholesterol levels plateaued at approximately 151 mg, a 15% reduction from the basal value. In experiment 2, 44-week-old White Leghorn hens were fed corn-soybean meal diets containing either 0, 0.0290, 0.1198, or 0.2407 % lovastatin (analyzed values) for a period of 9 days. In comparison to day 0 values, egg cholesterol contents on day 9 were reduced only at the two highest drug levels, with maximum observed decreases of approximately 8 and 13 % when expressed as milligrams of cholesterol per gram of yolk and milligrams of cholesterol per egg, respectively. No drug residues were detected in acetonitrile extracts of eggs from hens fed the highest dietary levels of lovastatin in each experiment.