Furosemide Induced Electrocardiographic Alterations in High Producing Holstein Dairy Cows

Diuretics have several therapeutic advantages in dairy cows but there are different side effects such as acid-base and electrolyte imbalances which may affect the electrocardiographic parameters. Fifteen multiparous, clinically healthy, non-pregnant and high producing 4-year-old Holstein dairy cows at their early lactation period were randomly divided into 3 equal experimental groups. Furosemide was infused intravenously at 3 different doses containing group 1: 2.5 mg/kg; group 2: 5 mg/kg and group 3: 10 mg/kg. Electrocardiogram recordings and blood samplings were performed at prior and 1, 2, 3, 4, 5 and 24 hours after furosemide administrations. Sera after separation were assayed for sodium, potassium, chloride, calcium, magnesium and phosphorus concentrations. There were no significant changing patterns in P, R, S and T amplitudes. P-R, R-R, Q-T and S-T intervals increased significantly after furosemide administrations in groups 2 and 3. Electrocardiographic intervals in groups 3 were higher than other groups (P