Home-orienting behavior in rat pups: the effect of 2 and 3 generations of rehabilitation following intergenerational malnutrition.

In an earlier study in this laboratory, we examined home-orienting ability in rats with histories of intergenerational malnutrition that were rehabilitated postnatally with an adequate protein diet (Galler, 1979). Despite increased size and activity, 1st-generation rehabilitated pups showed no improvement in homing ability when compared to malnourished pups. In the current study, offspring of rats with intergenerational malnutrition were rehabilitated for 2 additional generations and tested for homing ability from postnatal Day 4 through Day 12. The pups rehabilitated for 2 and 3 generations did not perform as well as control pups, even though growth and activity returned to normal levels. Furthermore, the rehabilitated pups failed to demonstrate any preference for the nest on all days of testing; in contrast, control pups favored the nest quadrant by Day 8 of life. No significant improvement was evident on any measure from the 2nd to the 3rd generation of rehabilitation.