Vol. 12, Special Issue 11 (2023)

Author(s):
Mayank Patel, Anamika Pandey, Shamshad Ali, Preeti Verma, Prem Kumar and Vikrant Singh Chouhan

Abstract:
Heat stress poses a significant challenge in global livestock production systems, primarily due to increasing global temperatures linked to climate change. High ambient temperatures and humidity levels can adversely affect the health and productivity of livestock animals. In addition, it also compromises their immune system and makes them more susceptible to diseases. The duration of exposure to heat stress can either enhance or suppress immune functions in farm animals. This stress signal operates through the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic-adrenal-medullary (SAM) axis, influencing the immune response. The first line of defence against pathogens, known as innate immunity, is essential for immediate responses to infections. Heat stress has been observed to impair various components of the innate immune system in livestock animals. It can compromise the integrity of the skin and mucosal barriers, as well as reduce the proliferation of immune cells. Generally, it's believed that heat stress shifts the adaptive immune function from cell-mediated to humoral immunity, weakening the animals' immune responses. Understanding the immunological effects of heat stress is crucial for livestock producers and researchers to implement effective management strategies, ensuring the health and welfare of animals in the face of mounting climate challenges.