[Dynamics of thyroid hormones and hematological and biochemical indices in chronic nitrate poisoning in sheep].

Experimental researches were carried out on sheep, fed with forage, containing 0.6% nitrate in the dry substance of the ration with the aim to follow the dynamics of the thyroid hormones, respectively the functions of the thyroid gland and its connection with some hematologic and biochemical indexes in the blood (methaemoglobin, blood sugar, carotene and vitamin A). It is ascertained that T3 and T4 decrease during the development of chronic nitrate poisoning, and the blood sugar and methaemoglobin are increased. The quantity of carotene and vitamin A is decreased, as a hypovitaminosis condition of the animal organism is achieved.