THE ROLE OF THE LARGE-INTESTINE IN ACID-BASE-BALANCE IN SHEEP

Sheep, like many animal species, may suffer from a variety of conditio ns affecting the intestinal tract, of which diarrhoea is a symptom. Fa ecal bicarbonate loss may be high when the form of diarrhoea is severe or chronic and a metabolic acidosis may result. In this experiment, a study was made of animals with ileorectal anastomosis (gut-cut sheep) which had suffered chronic diarrhoea for about a year. Acid-base para meters measured in arterial blood were no different between gut-cut an d control sheep, in spire of a 14 times greater loss of bicarbonate vi a the faecal route in the former compared with the latter group. Gut-c ut sheep compensated fully for the faecal loss of base by retaining bi carbonate ions from the urine filtrate. Total bicarbonate loss (urine and faeces) was therefore similar in the two groups (about 4.3 mmol pe r kg body weight per day). There was no evidence of a respiratory comp onent in the compensation for the potential metabolic acidosis.