Effect of diet on gentamicin-induced nephrotoxicosis in horses.
Gentamicin sulfate-induced nephrotoxicosis was compared in 2 groups of horses fed different rations. Four horses were fed only alfalfa hay, and 4 other horses were fed only whole oats. Seven days after initiation of the diet, all horses were given gentamicin IV (5 mg/kg of body weight) every 12 hours for 22 days. Urinary gamma-glutamyl-transferase to urinary creatinine (UGGT:UCr) ratio was calculated daily, and serum concentration of gentamicin was measured at 1 and 12 hours after drug administration. Results indicated that horses fed oats had greater renal tubular damage than did horses fed alfalfa. Mean UGGT:UCr for horses fed alfalfa was 47.1 +/- 18.8 and was 100.0 +/- 19.0 for horses fed oats (P = 0.007). The UGGT:UCr in horses fed oats was greater than 100 for a total of 54 days; horses fed alfalfa had UGGT:UCr greater than 100 for only 7 days. Two horses not given gentamicin were fed only oats and 2 were fed only alfalfa. These horses had mean UGGT:UCr of 17.6 +/- 2.2 and 30.5 +/- 3.0, respectively. Mean peak and trough concentrations of gentamicin were statistically different for horses fed oats and those fed alfalfa (peak 23.16 +/- 1.87 and 14.07 +/- 1.79 micrograms/ml, respectively [P = 0.0001], and trough, 1.81 +/- 0.69 and 0.71 +/- 0.70 micrograms/ml, respectively [P = 0.0270]). Mean half-lives of gentamicin (estimated from peak and trough concentrations) for horses fed alfalfa (2.58 +/- 0.26 hours) and horses fed oats (2.88 +/- 0.27 hours) were not significantly different. Horses fed only oats had greater degree of gentamicin-induced nephrotoxicosis than did those fed only alfalfa.
Schumacher
J
J
Department of Large Animal Surgery and Medicine, College of Veterinary Medicine, Auburn University, AL.
Wilson
R C
RC
Spano
J S
JS
Hammond
L S
LS
McGuire
J
J
Duran
S H
SH
Kemppainen
R J
RJ
Hughes
F E
FE
D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D003404:Creatinine / Q000652:urine; D002523:Edible Grain; D005839:Gentamicins / Q000009:adverse effects* / Q000097:blood / Q000493:pharmacokinetics; D006207:Half-Life; D006734:Horse Diseases / Q000139:chemically induced* / Q000517:prevention & control; D006736:Horses; D007674:Kidney Diseases / Q000139:chemically induced / Q000517:prevention & control / Q000662:veterinary*; D000455:Medicago sativa; D015431:Weight Loss; D005723:gamma-Glutamyltransferase / Q000652:urine
D005839:Gentamicins; D003404:Creatinine; D005723:gamma-Glutamyltransferase