The role of diet in mother-infant reciprocity in the spiny mouse.

One-day-old spiny mouse pups responded preferentially to bedding soiled by lactating conspecifics fed the same diet as their mothers. Following this test, pups were fostered onto different-diet females. When retested at 84-96 hr of age, no preferences were shown for bedding soiled by a female fed the biological mother's diet vs bedding of a female fed the different diet. When tested again at 120-132 hr of age, however, the pups preferred the bedding associated with their foster mothers' diet. In a 2nd experiment, recently parturient females retrieved 1-day-old pups born of same-diet females faster than pups born to novel-diet females. These results indicate that pup preferences for chemical cues produced by lactating conspecifics can be altered by sufficient exposure to a 2nd female maintained on a different diet and that neonatal chemical cues, like maternal chemical stimuli, are diet-dependent.