Modeling feedback-driven behavioral adaptation in pigs under environmental pressure: a study of behavior modification

Area of Science:

• Animal Science
• Behavioral Science
• Agricultural Engineering

Background:

• Aggression and stress during herd mixing negatively impact pig welfare and productivity in commercial farming.
• Existing methods for managing stress during mixing are often insufficient or have negative welfare implications.

Purpose of the Study:

• To develop and evaluate an environmental pressure-feedback (EPF) model to mitigate stress and aggression in pigs during herd mixing.
• To assess the physiological and behavioral responses of pigs to the EPF model.

Main Methods:

• The EPF model was implemented using brief feed withdrawal and spatial crowding, combined with resource-based feedback.
• Behavioral indicators (fight frequency, skin lesions) and physiological markers (cortisol, chromogranin A, glucose, body temperature, heart rate) were measured.

Main Results:

• EPF treatment significantly reduced pig aggression, indicated by decreased fight frequency and skin lesions.
• EPF-treated pigs exhibited significantly lower cortisol, chromogranin A, glucose levels, body temperature, and heart rate compared to controls.
• These physiological changes demonstrate effective stress alleviation and attenuation of the sympathetic nervous system and hypothalamic-pituitary-adrenal axis activation.

Conclusions:

• The EPF model effectively mitigates stress responses in pigs during herd mixing.
• By modulating behavior through controlled pressure and enhanced feedback perception, the EPF model prioritizes feeding motivation and suppresses aggression.
• This study provides a novel strategy for improving animal welfare and productivity in commercial pig farming.