[Effects of hypophyseal Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly synthetic peptides on immunity, hemostasis, morphology and functions of the thyroid gland in neonatally hypophysectomized chicken and one-year-old birds].

Neonatal hypophysectomy in chicken produces enlarged follicles of the thyroid gland, accumulation of colloids, impressed follicular epithelium, increased nucleus-cytoplasm ratio in thyrocytes, atrophied inter-follicular epithelium, depressed immunity, development of hypercoagulation and depressed fibrinolysis. When hypophysectomy is performed in one-year-old birds the impairments developing in thyroid morphology, immunity and hemostasis are less pronounced. Peptides of the anterior (Lys-Glu-Asp-Gly) and posterior (Ala-Glu-Asp-Gly) thyroid lobes injected to hypophysectomized birds prevent atrophic changes of the thyroid gland, normalize immune and hemostatic parameters.