Semester of Graduation
Master of Science (MS)
Veterinary Clinical Sciences
Renal disease is a common ailment of captive reptiles that is often closely linked to chronic, subclinical states of dehydration. Currently, the diagnosis of renal disease in reptiles is poorly characterized and often relies on invasive diagnostic techniques (e.g., renal biopsy) for definitive diagnosis. A potential outlet for the further characterization of renal dysfunction in reptiles is the induction of dehydration by furosemide therapy. Furosemide is a loop diuretic that is commonly used in mammalian patients for the treatment of congestive heart failure. The utility of furosemide in reptiles is poorly characterized, however, both experimental and clinical utility of this medication has been documented in various chelonian and squamate species. The goals of this thesis were to confirm the utility of furosemide administration, to better characterize the diagnostic findings of dehydration or reduced renal function, and to determine the utility of urine for the diagnosis of dehydration in the red-eared slider and the corn snake. Twelve adult, male, red-eared slider turtles and five adult corn snakes (one female, five male) were used for this study. Turtles were randomly assigned to three different treatment groups in a complete-crossover study: 10 mg/kg furosemide q 12-hours, 4 doses; 5 mg/kg furosemide q 12-hours, 4 doses; and a control group. The snakes were also randomly assigned to one of two treatment groups: 10 mg/kg furosemide q 12-hours, 4 doses; and a control group. Baseline blood and urine samples were collected, and water and food were withheld for 48-hours. Blood and urine samples were re-collected, and they were given access to water and weighed over the next 48-hours. Urine and plasma osmolality measurements were also determined via freezing point osmometry for the red-eared sliders. The results of this study support the clinical utility of furosemide in the red-eared slider, as furosemide-treated turtles had evidence of prominent physical signs of dehydration (e.g., sunken eyes, skin tenting, drying of scales), significantly increased urine production and urine osmolality, and disproportionately decreased chloride concentrations due to furosemide administration. The utility of furosemide in corn snakes was not confirmed based on the results of this study, as the analysis of the hematologic, biochemical, and urine parameters post-dehydration did not reveal a significant difference due to treatment. In the slider turtle, changes in weight, USG, plasma and urine osmolality, blood urea nitrogen, phosphorus, magnesium, and total protein concentrations were found to be significant indicators of dehydration. Similarly, differences in weight, total protein, and USG were found to be useful for the diagnosis of dehydration in corn snakes.
Metcalf, Kathryn, "Effect of Furosemide Administration on Plasma Analytes and Urine Enzyme Excretion in Two Reptilian Species" (2023). LSU Master's Theses. 5737.
Available for download on Monday, January 01, 2024