Sodium and potassium concentrations in the intestinal fluids of the fowl, Gallus domesticus

1. Na and K concentrations in the luminal fluids on the jejunum, ileum and colon were measured in domestic fowl on diets containing different amounts of Na and K. 2. Physiological adjustments of the Na and K content of these fluids were observed to occur in all three intestinal segments. 3. Regulation of gastrointestinal losses of Na and K appears to be initiated in the anterior regions of the intestines of the domestic fowl and is maintained or amplified as the ingesta moves posteriorly.