The renal response of sheep to prolonged ingestion of sodium chloride

Abstract

The renal function of sheep; after the ingestion of solutions containing 0.89% sodium chloride and 0.5% sodium sulphate, 1.14% sodium chloride and 0.2% sodium sulphate, and 1.3% sodium chloride offered as the only source of drinking water for a period of 6 months, was studied and compared with that of sheep fed on an identical diet and provided with rain-water. The daily fluid intake and the quantity of urine excreted increased in proportion to the concentration of the sodium chloride ingested. The glomerular fi1tration rate and filtration fraction were increased in the sheep drinking the saline water, but the renal plasma flow was only slightly reduced. The observations indicate that the sheep is able to tolerate relatively high salt water by virtue of a renal adjustment which favours increased filtration and so the elimination of the ingested salt.