Severity and nature of acidosis in diarrheic calves over and under one week of age.

A prospective study of the severity of dehydration and acidosis was carried out in 42 calves under 35 days of age presented for treatment of neonatal diarrhea. Clinically the mean level of dehydration was 8 to 10%. The plasma volume was 65% of that in the hydrated calf but the calves only gained 6.5% in weight during therapy.Calves under eight days of age often had a lactic acidosis. Blood pH was 7.118+/-0.026 (mean +/- 1 standard error), bicarbonate concentration 18.8+/-1.3 mmol/L, base deficit 11.4+/-1.7 mmol/L and lactate of 3.6+/- 0.06 mmol/L. Calves over eight days usually had a nonlactic acidosis. Blood pH was 7.042+/-0.021, bicarbonate 10.8+/-1.0 mmol/L, base deficit 19.5+/-1.2 mmol/L and lactate 1.2+/-0.3 mmol/L. These values were all significantly different from those in younger calves.Over all calves there was a poor correlation between the severity of acidosis and dehydration(r=0.05). The severity of lactic acidosis was related to the severity of dehydration. Mean bicarbonate requirements to correct acidosis were calculated to be 200 mmol(17 g of sodium bicarbonate)and 450 mmol(37 g of sodium bicarbonate)in calves under and over eight days of age respectively. Both groups of calves required a mean volume of 4L of fluid to correct dehydration.