UC Davis

Stress originating from various sources such as physical, metabolic, immunological, and psychological factors can interact with and impair reproduction at all levels, from central systems in the brain to the functioning of reproductive organs. Though these effects have been demonstrated in both males and females in a range of species, stallions, and mares are still constantly exposed to stressful experiences and procedures, which may negatively affect their performance and predispose future offspring to negative health and behavioral outcomes. In donkeys, stress may relate to jacks not wanting to breed and dystocia in jennies. In this chapter, the effects of stress on stallions and mares’ reproductive physiology, fetal programming, and development of foals’ health and behavior will be discussed, along with prevention or possible approaches to minimize these factors prior to and during breeding procedures, foaling, and weaning processes.