Evaluation of Plasma Cholesterol, Triglyceride, and Lipid Density Profiles in Captive Monk Parakeets (Myiopsitta monachus)

Abstract

Abstract To evaluate potential factors related to avian atherosclerosis, plasma cholesterol and triglyceride values were measured in 35 apparently healthy captive Monk parakeets (Myiopsitta monachus). The birds were categorized as healthy or at risk based on body condition score and weight and also evaluated based on their aviary environmental conditions. Plasma cholesterol (range) and mean was (4.655 -20.33) 8.008 mmol/L or (180-786) 309.65 mg/dl for all birds sampled. Plasma triglyceride (range) and mean for all birds sampled was (0.960-44.62) 4.364 mmol/L or (85-3952) 386.54 mg/dl. Thirty plasma samples were evaluated through density gradient ultracentrifugation lipid profiling techniques used to evaluate risk of cardiovascular disease in humans. The resultant lipid density profile graph was determined from the hydrated densities of the following lipids: triglyceride rich lipoproteins (TRL), low density lipoproteins (LDL) and subfractions, and high density lipoproteins (HDL) and subfractions. When analyzed using linear discriminant analysis, lipid profiles of the following lipid subfractions: TRL, low density lipoprotein 1 (LDL1), low density lipoprotein 2 (LDL2), and high density lipoprotein 2b (HDL2b) were increased (p<0.05) in at risk Monk parakeets when compared to healthy cohorts. However, gender and diet had no apparent effect on plasma cholesterol or triglyceride concentrations. As the first data for plasma cholesterol and triglyceride concentrations and lipoprotein density profiles in captive monk parakeets, a species known to be affected by atherosclerosis, plasma lipid concentrations and lipoprotein profiles may be useful markers for use in future investigation of atherosclerosis in birds. However, the consequence of increased plasma lipid concentrations and changes of lipoprotein profiles on avian health requires additional investigation.