Metoclopramide and (or) cimetidine administration to sheep fed tall fescue

Fifteen crossbred sheep were assigned randomly to 1 of 5 treatments: endophyte-free fescue diet (EF; 0% infected; 50% hay, 40% seed, 10% molasses); endophyte-infected diet (El; 95% infected; 50% hay, 40% seed, 10% molasses); El + 15 mg metoclopramide/kg body weight, 3 times/w; El + 9.0 mg cimetidine/kg body weight, twice daily; or El + metoclopramide + cimetidine. Both diets contained 92% dry matter (DM), 94% organic matter (OM) and 12% crude protein. All sheep were housed in individual metabolism stalls at 30 C, 14-h light:10-h dark for 18 d. Serum prolactin, respiration rate, heart rate or ear tip, coronary band and rectal temperatures were not affected by any of the treatments after 18 d (P > .10). No differences were detected in nutrient digestibilities except for treatment with metoclopramide + cimetidine, which produced decreased DM, OM and energy digestibilities. Sheep fed the El diet did not exhibit typical fescue toxicosis; therefore, the use of metoclopramide and(or) cimetidine to prevent toxicosis could not be evaluated.