Calculation of body surface area of corn snakes (Pantherophis guttatus) utilizing computed tomography

OBJECTIVE: To determine the K-constant for body surface area calculation from body weight in corn snakes (Pantherophis guttatus) through the use of computed tomography (CT) measurements. ANIMALS: 12 adult corn snakes held by North Carolina State University for research purposes underwent CT between November 2022 and January 2023. METHODS: Each snake had a CT scan, physical examination, and body weight measurement. CT images were uploaded into software able to perform 3-D reconstruction and measure body surface area. The species-specific K-constant was determined using nonlinear regression analysis between body surface area and (body weight in grams)2/3. RESULTS: The mean body weight of the 12 adult corn snakes was 228 g, with a mean body surface area of 505.1 cm2. The calculated K-constant was 13.6 (P < .001). The resulting formula for body surface area in corn snakes is BSA in cm2 = 13.6 X (body weight in grams)2/3. CLINICAL RELEVANCE: The body surface area formula developed for corn snakes will allow for improved dosing accuracy for medications with low therapeutic safety margins. Additional pharmacokinetic and pharmacodynamic studies are necessary to determine the safety and efficacy of individual medications.