Abomasal ulcers: Do ranitidine or omeprazole prevent phenylbutazone-induced lesions in sheep?

Abstract

Treatment and prevention of gastric ulcers are well known in monogastric animals; however, there are uncertainties about the preventive effects of acid-reducer drugs, their dosages and the best route of administration to ruminants. The object of this research was to test the preventive actions of ranitidine and omeprazole on abomasal ulcer development in sheep treated with a high dosage of non-steroidal anti-inflammatory drug. Eight healthy adult sheep with abomasal cannula were distributed in two contemporary and balanced 4 × 4 Latin squares (eight animals per group). For seven days, animals in the control group received high doses of phenylbutazone (4.4 mg/kg, every 12 h) while the treated groups received the same high doses of phenylbutazone plus an acid-reducer drug, namely 2 mg/kg of intravenous ranitidine every 12 h; 0.4 mg/kg of intravenous omeprazole; 4 mg/kg of oral paste omeprazole, both once a day. Intravenous omeprazole caused phlebitis, increasing serum fibrinogen content, and 75 % of the treated animals were diagnosed with type 1a ulcers in abomasal mucosa. Oral omeprazole showed no adverse effects, but was not effective in preventing type 1a ulcer in 50 % of animals, which was the same amount as diagnosed in control group. Despite of a minor heart rate increase, ranitidine treated animals showed only 37.5 % of abomasal injuries. Based on clinical findings, intravenous ranitidine is apparently better than omeprazole in prevention of abomasal ulcers, but another kind of experimental design comparing group by group is required and strongly recommended to ensure the beneficial effect of ranitidine.