Similar to human OCD, animals can develop repetitive, purposeless behaviors. Examples include tail-chasing, flank-sucking in Dobermans, or psychogenic alopecia (over-grooming to the point of hair loss) in cats. These behaviors often trigger the release of endorphins, helping the animal cope with a stressful environment. The Role of Behavior in Livestock and Welfare

Lethargy, anorexia, and decreased social interaction are evolutionary adaptations to conserve energy during infection. Pain Assessment: