Abstract
Our previous study showed that the hardness of food could work as a conditioned stimulus (CS) for the conditioned food aversion (Sako et al., 2001). In the present study, behavioral characteristics of the rats aversive-conditioned to the food with qualities of taste and hardness were investigated. For the CS, 4 types of pellets, such as hard and sweet (HS), soft and sweet (SS), hard and none taste (HN) and soft and none taste (SN), were used. All pellets contained same nutrition, but sweet pellets contained 5% sodium saccharin additionally. When the rats were aversive-conditioned to HS or SS with 0.15M LiCl i. p. (2% BW), they avoided all of foods with sweet quality even if their hardness were not same as CS. On the other hand the rats aversive-conditioned to HN or SN avoided CS, but they did not avoid other foods with sweet taste, even if they had same hardness of CS. These results suggest that rats acquired the conditioned food aversion give taste priority over hardness on their food choice. [Jpn J Physiol 54 Suppl:S204 (2004)]
