Inadequate saline selection by Mongolian gerbils fed a cation exchange resin in the diet

Mongolian gerbils (42 male, 42 female) were tested for presence of a special hunger for minerals. Three groups were fed a mineral-free mash which contained a cation exchange resin and chelator. Three additional groups received the same mash but with a nonnutritive fiber in place of the resin and chelator. For 15 days, one group in each dietary plan was given ad libitum choice between a mineral solution and distilled water (DW). A second group in each arrangement drank only DW, and the third received just the mineral solution. All gerbils fed the fiber, as well as the animals given only the mineral solution while fed the exchanger, survived the period and showed nil or mild weight losses. In contrast, the two groups given either fluid choice or DW alone while receiving the exchanger survived the period in 43 percent and 29 percent of the cases, respectively; and the survivors exhibited marked decrements in body weight.