Alteration of Egg Yolk Cholesterol Content and Plasma Lipoprotein Profiles following Administration of a Totally Synthetic HMG-CoA Reductase Inhibitor to Laying Hens

PD123244-15[(±)-(R*,R*)-3,4-dibromo-β,δ-dihydroxy-2-(4-fluorophenyl)-5-(1-methylethyl)-1H-pyrrol-1-heptanoic acid, sodium salt], a totally synthetic HMG-CoA reductase inhibitor, was fed to laying hens at dietary levels of either 0, 0.0091, 0.0273, or 0.0819% for 20 days (experiment 1) or 0, 0.0273, 0.0546, or 0.0819% for 42 days (experiment 2). In each experiment, PD 123244-15 generally had little effect on egg or yolk weights, while hens fed 0.0819% PD 123244-15 produced fewer (P < 0.05) eggs than the other three groups. Egg cholesterol contents varied inversely with the amount of dietary PD 123244-15, with a maximum reduction of approximately 30% obtained at the highest drug level in both experiments. With the exception of samples from hens fed 0.0091% PD 123244-15, plasma total cholesterol and triglyceride concentrations also varied inversely with the dietary amount of PD 123244-15. Further analysis of the plasma samples by high-performance gel permeation chromatography revealed that the PD 123244-15-mediated lowering of total cholesterol and triglycerides was almost totally accounted for by a reduction in the VLDL fraction. On the basis of reversed-phase HPLC analysis, no drug residues were detected in egg yolk and albumen extracts from hens fed 0.0819% PD 123244-15.