Effects of double intravenous furosemide administration at different doses on clinical variables, electrocardiographic indices and serum electrolytes in miniature donkeys.

The intravenous (IV) usage of diuretics such as furosemide may cause changes in clinical variables, electrocardiographic (ECG) indices and some serum electrolytes concentrations in miniature donkeys. The purpose of this study was to evaluate the effects of double intravenous (IV) administration of furosemide at different doses on the clinical variables, ECG indices and serum electrolytes levels in miniature donkeys. A total of 21 clinically and para-clinically healthy miniature donkeys with a mean age of 6.00 ± 1.00 years and weight of 95.00 ± 5.00 kg were used. The animals were randomly divided into three groups of control (normal saline) and low- (1.00 mg kg^-1) and high-dose (2.00 mg kg^-1) of furosemide. Two IV injections with 12-hr interval were administered in each animal. The clinical and ECG parameters were measured at 0 (baseline), 2 (T2), 24 (T24) and 48 (T48) hr after drug administration. Serum concentrations of electrolytes were measured at T0, T24 and T48. The results of this study showed no changes in clinical variables (heart rate, rectal temperature and respiratory rate) and ECG indices (amplitude and duration of P, QRS and T waves and duration of PR, QT and RR intervals) as well as no significant changes in serum electrolytes (sodium, potassium, chloride, phosphorus, calcium and magnesium) levels. Although no significant effect on clinical variables, electrolytes levels and ECG indices after double IV administration of furosemide (1.00 and 2.00 mg kg^-1) in miniature donkeys was observed, absence of these effects does not mean that furosemide had no pharmacological effect.