Pineal-adrenal Relationship under Thermal Stress with Emphasis on Effect of Pineal Proteins on Endocrine Profiles in Chemically Adrenalectomized Does

Pineal-adrenal relationship was studied with the primaiy objective to determine the influence of total precipitated pineal protein on endocrine function in chemically adrenalectomized does to alleviate heat stress. Melatonin and glucocorticoids secretions and several other endocrine parameters reflecting the animals well being were determined over a period of a week after does had been exposed to 40°C and 60% RH for 10 days. The study was conducted for a period of seventeen days under psychrometric chamber. Animals were served as self controls prior to start of the experiment. Blood samples were drawn on day 0 and day 10 to establish control and thermal stress values, respectively. Chemical adrenalectomy was achieved using metyrapone followed by exogenous total precipitated pineal protein treatment. Chemical adrenalectomy significantly affected plasma levels of the different endocrine parameters studied. Total precipitated pineal proteins successfully and significantly relieved the animals from adverse affect of heat stress and metyrapone treatment. This is evident from the findings that most of the endocrine parameters studied were influenced by pineal protein indicating their antistress properties. In conclusion this result established that total precipitated pineal proteins have significant influence upon adrenal cortex secretions in relieving thermal stress in does.