Nitrogen metabolism in the ovine stomach: 4. Nitrogenous components of the abomasal secretions

Abstract

SUMMARY The major nitrogenous components of gastric juice were determined in sheep with innervated pouches in the fundic and pyloric regions of the abomasum. Fundic secretions contained mean levels of 36–55 mg total-N/100 ml in the fluid fraction, and pyloric secretions contained 38–70 mg/100 ml. Of this, 65–76% and 75–91% could be attributed to protein, in the fundic and pyloric secretions respectively. Tungstic acid was found to be the most suitable precipitant of proteins in the gastric juice. Dissolved mucin accounted for 2–16% of the total-N in the fluid fraction of the fundic secretions, and for 6–14% in the pyloric secretions. Urea + ammonia contributed 2·8–13·4% of the total-N. The daily output of nitrogen by the fundic region of the abomasum, including that contributed by the cellular debris and visible mucus, was calculated at 0·46–2·4 g. The comparable values for the pyloric region varied between 0·05 and 0·37 g N/day. The electrophoretic patterns of the abomasal secretions were similar to those reported for human gastric juice.