Turnover of Tritiated Water and 22Sodium in Captive Rabbits (Oryctolagus cuniculus)

Abstract

The intakes of water and sodium by captive rabbits (Oryctolagus cuniculus) were compared with estimates derived from the turnover of tritiated water and 22Na. Water intake and isotopic water turnover estimates differed by less than 5% but 22Na turnover, when compared with sodium intake, was consistently lower by about 23%. The mean rate of water turnover was 68.5 ± 15.4 ml/kg day and the mean rate of 22Na turnover was 3.6 ± 0.7 mEq/kg day. The results of this study show that tritiated water and 22Na turnover provide good estimates of water and sodium intake in rabbits. A number of useful applications for the 22Na turnover technique in physiological and ecological studies are discussed.