Researchers found that anticoagulant rodenticides can cause rats to develop a dislike for certain foods due to symptoms they experience after ingesting the poison. This taste aversion is linked to the disruption of the vitamin K cycle in the rats' bodies, which affects how their bodies process certain proteins. The aversion fades as the rats' bodies recover from the effects of the poison. This discovery sheds new light on how anticoagulants can impact animals' behavior and preferences.