Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: December 10, 2009
Publication Date: March 19, 2010
Citation: Lay Jr, D.C. 2010. The Physiologic Response to Stress and its Effects on Swine Reproduction [abstract]. Journal of Animal Science Supplement 1. p. 9. Technical Abstract: When exposed to a stressor, swine invoke behavioral and physiologic responses which are designed to enable the individual to cope with the negative effects of the stressor. The activity of the hypothalamic-pituitary-adrenal axis is increased resulting in elevated corticotropic releasing factor (CRF), adrenocorticotropic hormone (ACTH) and glucocorticoids. Similarly, the sympatho-adrenal axis is activated resulting in an increase in epinephrine. The extent to which these systems are activated depends on both the duration and intensity of the stressor. The animal’s current disposition, for instance its nutritional state, health state, and level of arousal can also influence the extent to which the stressor may cause damaging effects. Whether the activation of the stress response in pigs influences measures of reproductive success depends on many factors, including: application of the timing of the stressor, intensity and type of the stressor, the animal’s stage of reproduction when exposed to the stressor, the animal’s genetic predisposition to stress susceptibility, and previous experiences of the animal. It is also known that short term stress can have an enhancing effect on reproduction while chronic stress is typically inhibitory of reproductive success. It is also important to note that a significant body of literature is contradictory, with some indicating that stress has little effect on swine reproduction. This presentation will review the current state of knowledge relative to the effects of stress on swine reproductive ability while focusing on the endocrinological events associated with the stress response and failure or success of reproductive function in swine.