Effects of a 0.3% cholesterol diet and a 20% fat diet on plasma lipids and lipoproteins in Quaker parrots (Myiopsitta monachus)

Abstract

Background Lipid disorders are common in captive psittacine birds, but associated changes in blood lipids and lipoproteins have not been well characterized. The Quaker parrot is prone to dyslipidemia and has been extensively used as an experimental model. Objectives We aimed to study the effects of a 0.3% cholesterol diet and a 20% fat diet on plasma lipids and lipoproteins in Quaker parrots. Methods Two crossover studies were performed with each diet. During each study, 12 parrots were divided into two groups fed the treatment or control diet for 2 weeks. After a 2‐month wash‐out period, the groups were reversed. At the end of each period, plasma lipidomics and lipoprotein profiling were performed. Data were analyzed by univariate tests adjusted for false discovery rates, volcano plots, and enrichment analyses. Results The cholesterol diet induced changes in many plasma lipids and lipoproteins. Total cholesterol and cholesteryl esters were significantly and markedly elevated. Ceramides were the second subclass of lipids that were elevated. Several glycerophosphocholines, sphingomyelins, and one diacylglycerol were also significantly elevated, albeit to a lesser magnitude. All lipoproteins were elevated, with the greatest increase seen in non‐HDL. The fat diet mainly resulted in a decrease in plasma glycerolipids and an increase in acylcarnitines. Lipoprotein plasma levels remained unchanged. Conclusions Quaker parrots fed a 0.3% cholesterol diet showed profound and complex dyslipidemic changes that could be used to further study lipid disorders and their management in psittacine birds. A 20% fat diet higher in n‐6 polyunsaturated fatty acids did not lead to dyslipidemia.

Effects of Atorvastatin and Rosuvastatin on Blood Lipids in Quaker Parrots (Myiopsitta monachus)

“…The 0.3% cholesterol diet leads to profound dyslipidemia in Quaker parrots, with broad changes to the plasma lipidome. 21 It was thought that statin effects would be more evident in hypercholesterolemic and dyslipidemic parrots, but no effect was observed in this investigation with either diet. Statins are inhibitors of cholesterol synthesis, thereby limiting endogenous cholesterol production, whereas exogenous cholesterol was provided to the Quaker parrots through dietary supplementation.…”

“…The cholesterol diet caused some profound changes in the lipidome, but these results were already reported in previous studies and were similar in the current study. 15,21 As these changes were not the purpose of this study and were previously reported, they were not reiterated here.…”

Case Series of Disseminated Xanthogranulomatosis in Red-crowned Parakeets (Cyanoramphus novaezelandiae) with Detection of Psittacine Adenovirus 2 (PsAdV-2)

“…Given that seed-based diets are known to be unbalanced for psittacine birds and often high in fats [ 43 ], this nutritional imbalance may be a predisposing factor for acquiring xanthogranulomatous diseases, as stated before [ 28 ]. In contrast, recently published experimental studies in Monk Parakeet ( Myiopsitta monachus ) provide some evidence that in the genesis of atherosclerotic lesions, cholesterol concentration of the diet is more important than the overall fat content [ 44 ]. Lipometabolic disorders are suspected to be the main reason for the pathogenesis of disseminated coelomic xanthogranulomatosis, since concurrent atherosclerotic lesions were seen [ 28 , 29 ].…”