BREATH HYDROGEN EXCRETION BY HEALTHY CATS AFTER ORAL-ADMINISTRATION OF OXYTETRACYCLINE AND METRONIDAZOLE

Breath hydrogen excretion over a period of three hours was measured to evaluate carbohydrate malassimilation in healthy cats treated orally with antibiotics, Both an absorbable carbohydrate (xylose) and a non-a bsorbable carbohydrate (lactulose) were administered during the tests to evaluate the changes in the intestinal mucosa and the population of bacteria within the intestinal lumen, Overall, the effects of oxytetr acycline and metronidazole on breath hydrogen excretion were not signi ficantly different, However, the treatment effect with an antibiotic d id significantly change breath hydrogen excretion after xylose adminis tration (P<0.05) within groups, Similarly, with each antibiotic,breath hydrogen excretion was affected significantly (P<0.001) by the time a fter the administration of the carbohydrate. Treatment with each antib iotic also interacted significantly with this time effect (P<0.05) wit hin groups, After lactulose administration, there was a trend within g roups for the type of antibiotic to interact with the treatment effect on breath hydrogen excretion (P = 0.09), After oxytetracycline treatm ent, more hydrogen was exhaled during the first 120 minutes after lact ulose administration than in the pre-antibiotic test, whereas after me tronidazole treatment, less hydrogen was exhaled between 60 and 180 mi nutes after lactulose administration, After treatment with either oxyt etracycline or metronidazole, more hydrogen was exhaled after xylose a dministration. Obligate anaerobes could be isolated from samples of sm all intestinal fluid obtained endoscopically after oxytetracycline tre atment, but they could not be isolated after treatment with metronidaz ole.