ECG Changes in Acute Experimental Ruminal Lactic Acidosis in Sheep

For induction of ruminal acidosis, 10 clinically healthy three years old non pregnant female sheep were selected. Prior to the infusion of sucrose (0 hour), rumen and blood samples were obtained in order to determine baseline rumen and blood pH, respectively. Electrocardiogram (ECG) was also recorded. Acute ruminal acidosis was induced experimentally with sucrose at a dose of 18g kg-1 body weigh through rumen fistula. ECG was recorded and blood and rumen samples collected at 3, 6, 9, 12, 15, 18, 21, 24, 30, 36, and 48 hours after the infusion of sucrose. Results indicated that blood and rumen pH decreased significantly at 15, 18, 21, 24, 30, 36 and 48 hours and at 3, 6, 9, 12, 15, 18, 21, 24, 30, 36 and 48 hours, respectively. Acidosis produced a marked increasing in heart rate and a decrease in PR interval at 15 and 18 hour significantly with little apparent effect on the ST and PR segment. The P amplitude increased significantly at 6, 9, 12, 15, 18, 21, 24 and 30 hours. The T amplitude increased significantly at 9, 12, 15, 18, 21, 24, 30 and 36 hours. The RR interval decreased significantly at 6, 9, 12, 15, 18, 21, 24, 30, 36 and 48 hours. In conclusion acute ruminal acidosis caused significant changes in ECG of sheep though there was not any detectable arrhythmia in the ECG in acute ruminal acidosis.