Diet type, fasting duration, and computed tomography hepatic attenuation influence postprandial plasma lipids, β-hydroxybutyric acid, glucose, and uric acid in bearded dragons (Pogona vitticeps).

Abstract

Objective: To evaluate the effect of fasting duration and diet types (plant-based and crickets) on plasma glucose, uric acid, cholesterol, triglycerides, nonesterified fatty acid, β-hydroxybutyric acid (BHBA), and bile acids in bearded dragons after a single feeding.

Methods: Hepatic fat content was estimated by a CT scan. Animals were randomly divided into 2 groups, each receiving either a plant-based or cricket diet. Following a 72-hour fasting period, animals were gavage fed their respective diets. Blood samples were collected at 0, 6, 12, 24, 48, and 72 hours postfeeding for biochemistry analysis. Data were analyzed using linear mixed models.

Results: 22 bearded dragons were used. Plasma glucose, uric acid, bile acid, nonesterified fatty acid, and BHBA concentrations varied significantly over time between the 2 diets. Cholesterol and triglycerides remained stable throughout the fasting period. Glucose peaked for 48 hours in the plant-based group. Uric acid increased in the cricket group but declined in the plant-based group. Bile acids increased in both groups, with a more pronounced and sustained increase in the cricket group. Nonesterified fatty acid and BHBA decreased within the first 12 hours in both groups, with a subsequent rebound, except for BHBA in the plant-based group. Hepatic CT attenuation significantly influenced multiple analytes.

Conclusions: A fasting period of 48 to 72 hours depending on analytes is recommended in bearded dragons before biochemistry analysis.

Clinical relevance: Fasting periods shorter than 48 to 72 hours may lead to erroneous interpretation of plasma biochemistry in bearded dragons. The findings of this study also suggest a feeding frequency of 2 to 3 days for adult bearded dragons.