Saccharin hoarding by albino rats: further evidence on incentive and object retrieval.

Albino rats were allowed to retrieve dental pledgets soaked in water or pledgets soaked in 1.0% saccharin solution from wooden alleys into their home cages. Under ad lib conditions more saccharin pledgets were hoarded than water pledgets, but during water deprivation this preference was reversed. If rats were given saccharin pledgets alone, hoarding did not decline during water deprivation. Rats showed the ad lib saccharin preference although they did not hoard their normal diet of food pellets, and it was maintained in animals that had received saccharin since weaning. Hence sweetness of taste is a property of objects that can induce hoarding, and the reversal in hoarding during deprivation is due to an increased preference for water rather than a diminished saccharin preference. This indicates that incentive properties of objects are crucial to the expression of this species-typical behavior.