Body fluid osmolality and hydric relations of frogs from monsoonal northern Australia

摘要: The osmolality and solute composition of body fluids, water exchange with the substrate, role bladder, response to seasonal availability were examined in frogs from monsoonal northern Australia. Using a technique involving temporary ligation, lymph was more easily obtained Rhinella marina than Litoria caerulea Cyclorana australis. Lymph accumulation rapid hydrated or full bladders. Differences between blood-plasma insubstantial. On semi-solid agar-solute substrates across range potentials, hygroscopic cocoon australis absorbed moisture. With removed, depended on direction frog-substrate potential difference. acts as physical barrier that breaks continuity frog substrate. mass moist soil variable soil. In laboratory, access regularly replenished bladder store, urine remained low. no available, urea concentration store increased, but reabsorption modulated plasma osmolality. empty bladders, increased loss. Models indicate size, fluid, initial rates loss influence burrowed soilfilled pots during dry season. After two days, excavated fully hydrated. As dried, developed cocoons retained fluid. Plasma over time, approached osmolality, major contributing osmolyte. ensure survival this burrowing species prolonged periods. collected late season adopted absorbing postures Water (-31 kPa) permitted cutaneous drinking. indicated dehydration, differed laboratory active toads.