“…This indicates that intestinal phosphate absorption is similar in ruminating lambs, in which large amounts of phosphate enter the digestive tract via the large volume of secreted saliva (Watson, 1933;Smith, Kleiber, Black & Baxter, 1955;Kay, 1960;Tomas, Moir & Somers, 1967;Compton, Nelson, Wright & Young, 1980;Mafias-Almendros, Ross, R. & Care, 1982;Scott, McLean & Buchan, 1984b) and in milk-fed lambs, where probably much less phosphate is secreted by the salivary glands. Unfortunately data on phosphate secretion by the salivary glands are not available for milk-fed lambs, but it has been shown that much less phosphorus enters the digestive tract via the saliva in milk-fed calves compared to cattle (Smith, Kleiber, Black & Lofgreen, 1956;Boehncke, Langner & Weissmann, 1981;Gropp, Kdnig, Feuchter & Muller, 1982). The transport mechanisms of the intestinal epithelium for phosphate therefore do not seem to adjust to the increasing influx of endogenous phosphate into the digestive tract during rumen development.…”