RESUMO
OBJECTIVE: To determine the effects of preoperative erythromycin or combined dexamethasone/vitamin C treatment on postoperative abomasal emptying rate in cows undergoing surgical correction of abomasal volvulus (AV). STUDY DESIGN: Prospective, controlled, clinical study using a convenience sample. ANIMALS: Lactating Holstein-Friesian cows (n=45) with AV were alternately assigned to 3 groups (n=15): group C: untreated (control); group E: erythromycin (10 mg/kg intramuscularly [IM]); group D: dexamethasone (0.02 mg/kg intravenously [IV]) and vitamin C (10 mg/kg IV). METHODS: Drugs were administered 1 hour before surgical correction of AV. D-xylose solution (50%, 0.5 g/kg body weight) was injected into the abomasal lumen during surgery. Jugular venous blood samples for determination of serum d-xylose concentration were periodically obtained. Time to maximal serum D-xylose concentration (T(max-model)) was pharmacokinetically determined. RESULTS: Abomasal emptying rate was significantly (P<0.05) faster in group E (T(max-model)=182+/-69 min; mean+/-SD) than in group C cows (T(max-model)=237+/-64 min). Abomasal emptying rate was similar in group D (T(max-model)=196+/-47 min) and group C. Both treatments improved postoperative milk yield within 1 day after surgery. CONCLUSION: Preoperative injection of erythromycin (10 mg/kg IM) is an effective method for ameliorating postoperative abomasal hypomotility in cows with AV. CLINICAL RELEVANCE: Parenteral erythromycin can be recommended for preoperative treatment of cows with AV.
