Abstract

Animals possess various inherent mechanisms to cope up with the changing environmental conditions. It has been observed that the ability of animals to adjust with these climatic extremes is related to their level of adaptation and this is inversely correlated with their production potential. Stress tolerance in livestock is determined through various mechanisms and metabolic neuroendocrine regulation is one of the crucial pathways by which the animal survives the stressful condition. The Hypothalamic-Pituitary- Adrenal (HPA) axis plays a significant role in the release of several neurotransmitters and hormones which regulates the thermoregulatory mechanisms in animals. The Thyrotropin-Releasing Hormone (TRH), Thyroid Stimulating Hormone (TSH) and Thyroid Hormones (T3 and T4) are the components of metabolic pathway in regulating body heat production. Thyroid hormones are recognized as the key regulators of metabolic activity in domestic animals. Further, leptin secreted from adipocytes also has a great influence in regulating whole body energy metabolism and may be attributed as a “metabolism modifier”. The release of cortisol stimulates physiological and metabolic responses necessary to optimize the animal capacity to overcome a stressful factor by increasing the energy availability by decrease of cortisol levels. Generally, thyroid hormones, cortisol and leptin are considered to be important biological markers of neuroendocrine pathways for the regulation of metabolic adaptation mechanisms during stress in livestock.

Keywords: Livestock; Stress; Adaptation; Neuro-endocrine; Thyroid hormones; Cortisol; Leptin