Urine analysis of three rodent species with emphasis on calcium and magnesium bicarbonate.

The urine composition of three rodent species, mole rat Spalax ehrenbergi, the golden hamster Mesocricetus auratus and the white rat Rattus norvegicus was studied. These three species represent different degrees of fossoriality. The results show that the urine of the species that show a higher degree of fossoriality, the mole rat and the hamster, contain high values of calcium and magnesium bicarbonates when compared with the white rat. From these results it may be assumed that the mole rat as well as the hamster can use the kidney as a pathway for releasing bicarbonate and carbonate. This mechanism may reduce the CO2 concentration in their hypercapnic environment.