Effects Of Olfactory And Learned Safety On Poisoned Partner Effect In Rats

When animals were first presented with a novel-tasting food, they will show reluctance to consume it before ascertain there is no risk, this phenomenon is called the neophobic response. If the bodily malaise had no appeared after ingested the food, the intake will increase gradually, this process is defined learned safety. In contrast, if visceral malaise or poisoning symptom had happened following ingestion of some unfamiliar food, the animal will display aversive responses and avoid behaviors when meet the food again, this is called conditioned taste aversion (CTA). CTA can also be caused by observational or social learning, for example, animals interacted with poisoned conspecific demonstrator will reduce the intake of their diet that demonstrator eaten, this phenomenon is called poisoned partner effect (PPE). PPE could make unpoisoned animals to avoid ingestion of the poisonous food, and has great biology significance for subsistence of animals. Whereas the avoid behavior and taste aversion for toxic bait in the unpoisoned animals will greatly depress efficiency for control of pest. Hereby, studies in the influencing factor and the mechanism of PPE has important significance for control of pest.Olfactory information plays an important role in the life of rodent, and the learned safety could block CTA effectually, but the effects of olfactory information in the PPE, and whether learned safety could block PPE is unknown now.In the present studies, rats were injected LiCl intraperitoneally following intaked saccharin solution to establish CTA to sweet taste. Then the effect of odors remained by poisoned animals on taste preference of normal animals was examined by exposing rats didn't drink saccharin solution to the environment where stayed by rats before or after CTA. The role of olfactory information in PPE was explored, and further whether learned safety can eliminate PPE was explored.Results:1,After established CTA to saccharine, preference rate of rats was significant lower than before.2,Exposed on environment where stayed by rat after CTA to saccharine, preference rate was significant lower in unpoisoned rats.3,Exposed on environment where stayed by rat before CTA, preference rate of unpoisoned rats was significant lower, too. But it had no significant differences(P=0.079).4,Unpoisoned rats had the same aversion to saccharine after interaction of rats had established CTA to saccharine.5,The learned safety to saccharine acquired via pre-expose saccharine could completely eliminate PPE.Conclusions:1,The odor remained in the environment by rats both before and after the establishment of CTA could induce CAT, but the odor remained by rats after the establishment of CTA have stronger effect. The odor released by poisoning rats play an important role in the establishment of PPE. Olfactory sensation is an important way of the social transmission of food preferences.2,In pest control using toxic baits, giving innoxious baits before toxic baits to establish learned safety, could attenuate CTA and block PPE.