Ovine Ruminal Acidosis: Clinical Studies

SUMMARY When 8 fistulated, pregnant sheep were given ruminal infusions of purified ration, induction of, and recovery from, ruminal acidosis did not produce abortion, congenital abnormalities, or retained placentas in 4 sheep. Of 14 fistulated sheep kept in metabolism crates and given (through the fistula on a 24-hour basis) corn sugar (100 or 1,000 g/day), casein, and minerals, all sheep developed ruminal acidosis. Two nonfistulated wethers orally given 1,000 g of corn sugar per day for 2 days also developed ruminal acidosis. In these 16 sheep, short-term (24-hour) increases in ruminal feeding of corn sugar resulted in a decrease in ruminal pH. With the onset of ruminal acidosis, the 16 sheep developed central nervous system (cns) depression, increased heart and respiratory rates, congested mucous membranes, salivation, and ruminal stasis; some sheep had increased rectal temperature or diarrhea. Five of the sheep given 1,000 g of corn sugar per day died. Changes associated with ruminal acidosis were decreased mean values for blood pH and transketolase and increased mean values for packed cell volume (pcv), blood glucose, thiamine pyrophosphate effect, blood pyruvate, and blood l-lactate.