Climate change impact on immune response in sheep

Abstract

Sheep are considered one of the most resistant species with respect to climate change and high environmental temperatures. Most studies have focused on the effects of heat stress on the physiological mechanisms of adaptation in dairy cows; few studies have dealt with dairy sheep physiology and, above all, with sheep immunological responses. This chapter will focus on the complex network of mechanisms activated by heat stress as affecting immune responses in sheep. In particular, heat stress will be discussed as an attempt to animals' homeostasis, thus affecting immune system and inducing activation of inflammatory pro cesses. In particular, it will present a synopsis of the knowledge of the sheep immune system, and the changes induced by heat stress on both innate and adap tive immunity. Recent data suggesting a role of heat stress on perturbation of oxidative balance and the consequent effects on the immune system will be dis cussed. Finally, a discussion on the effects of heat stress on sheep mammary immunity will be presented.