[Effects of calcium on the course of strontium toxicosis].

Chronic intake of Sr for 20 days by chickens caused in them a delay in body mass increase and symptoms of rickets in spite of complete provision with vitamin D. There were low levels of Ca, P, enhanced activity of alkaline phosphatase in the serum, inhibited mineralization of bone tissue, reduced levels of vitamin D-dependent calcium-binding protein, Sr accumulation in various tissues. Enrichment with Ca of the chickens ration diminished the above signs of Sr toxicosis. It is suggested that a protective effect of Ca in chronic Sr toxicity may be due to more active discrimination of Sr against Ca in intestinal assimilation of these cations.