Personality in swine

Abstract

There are approximately 977 million domestic swine (Sus scrofa domesticus) that live on farms across the world. Knowledge of individual variation in behavior, morphology and productivity has been the basis for artificial selection of this domestic species for thousands of years. Determining personality traits among group living swine may help to identify certain individuals that possess an increased ability to cope with, or a heightened sensitivity to, environmental and/or social stress. There have been approximately 48 studies that investigated behavioral variation in commercial swine. The majority of these studies have been limited to animals aged seven months or younger. Experimental trials are the predominant method of measuring behavioral differences among swine and include such methods as physical restraint, open field tests, human approach tests, novel object tests, and feeding competitions. Previous research on swine personality has reported the existence of multiple traits such as aggressive, exploratory or fearful, as well as dichotomous coping styles (e.g., proactive vs. reactive). Despite excellent work on themes such as environmental influences and trait development, scholars examining personality in swine have not yet fully explored proximate and ultimate explanations of swine personality traits. Considerable effort has gone into identifying personality traits and coping styles in swine in order to evaluate the relationship between behavior, health, and production (e.g., mothering skills, weight gain, lean meat percentage). Knowledge of individual personality traits among domestic swine may help the pork industry to adjust husbandry practices and housing conditions, which are currently under transition due to market-driven welfare concerns.