Dynamics of hormonal status of young simmental breed in conditions of various housing systems

The work is devoted to the study of the dynamics of the hormonal status of young cattle depending on the housing system. In this regard, the functional activity of the endocrine glands was studied: the adrenal cortex, pancreas, thyroid and genital glands. The content of cortisol, insulin, testosterone, thyroxine in the blood serum was determined during the periods: immediately after birth, at the daily age, after reaching 1, 2, 4, 6, 8, 12 and 18 months. It was found that the cortisol content in the blood of newborn calves (148.6–152.7 nmol/l) was the maximum. By the end of the first day, the level of this hormone decreased by an average of 7.07–17.62%. By 18 months, the cortisol content was in the range of 32.3–39.3 nmol/l. The bulls of the control group were more susceptible to the effect of adverse environmental factors. The highest level of thyroxine (169.2–173.4 nmol/l) was at birth. In subsequent periods, the thyroxine content decreased. Activation of the thyroid gland was noted at the age of 8 and 12 months. This is due to the period of puberty. The maximum values of insulin concentration in the blood were noted in daily bulls (1.28–1.83 mmol/l). Thus, in the control group, the insulin level increased by 38.64% compared to the data at birth, in groups 2 and 3, respectively, by 31.49 and 22.48%. At the age of one month, the level of pancreatic hormone, compared with baseline data, increased by an average of 3.87–5.30%, at the age of two months – by 2.27–8.66%. In subsequent age periods, the concentration of this hormone changed slightly. Relatively low testosterone levels were recorded in the first six months (0.47–1.32 nmol/l). At the age of 6, 8 and 12 months, the testosterone content increased to 2.97–3.34, 3.78–4.29 and 9.84–12.15 nmol/l, respectively. The highest testosterone content was found at the age of 18 months (13.24–15.48 nmol/l).

1. Babichev V.N. Organizatsiya i funktsionirovanie neyroendokrinnoy sistemy [Organization and functioning of the neuroendocrine system]. Problemy endokrinologii. 2013; 1; 59: 62–69. (In Rus.)

2. Luk’yanov V.N., Prokhorov I.P. Gormonal’niy status bychkov simmental’skoy porody i ee pomesey s gerefordskoy i sharolezskoy [Hormonal status of bulls of the Simmental breed and its crossbreeds with Hereford and Sharolez]. Izvestiya Timiryazevskoy sel’skokhozyaystvennoy akademii. 2015; 4: 95–105. (In Rus.)

3. Luk’yanov V.N. Formirovanie myasnoy produktivnosti skota simmental’skoy i cherno-pestroy porod i pomesey, poluchennykh pri skreshchivanii s bykami britanskoy i frantsuzskoy selektsii [Formation of meat productivity of cattle of Simmental and black-and-white breeds and crossbreeds obtained by crossing with bulls of British and French breeding]. Abstract of DSc (Ag). 2019: 45. (In Rus.)

4. Meerson F.Z., Pshennikova M.G. Adaptatsiya k stressornym situatsiyam i fizicheskim nagruzkam [Adaptation to stressful situations and physical exertion]. M.: Medicine. 1988: 256. (In Rus.)

5. Prokhorov I.P. Rost i obmen veshchestv u bychkov simmental’skoy porody pri ot”yeme ikh ot materey [Growth and metabolism in bulls of the Simmental breed when weaned from their mothers]. Izvestiya Timiryazevskoy sel’skokhozyaystvennoy akademii. 2012; 5: 98–106. (In Rus.)

6. Prokhorov I.P., Luk’yanov V.N., Pikul’, A.N. Vliyaniye ot”yemnogo stressa na gormonal’niy status bychkov [Effect of weaning stress on the hormonal status of bulls]. Trudy Kubanskogo agrarnogo universiteta. 2014; 4 (49): 135–140. (In Rus.)

7. Reznikov A.G. Endokrinologicheskie aspekty stressa [Endocrinological aspects of stress]. Mezhdunarodniy endokrinologicheskiy zhurnal. 2007; 4: 11–17. (In Rus.)

8. Rozen V.B. Osnovy endokrinologii [Fundamentals of endocrinology]. M.: Vysshaya shkola. 1984: 336. (In Rus.)

9. Ertuev M.M. Gormonal’niy profil’ i obmen veshchestv u telok pri vvedenii kortikotropina [Hormonal profile and metabolism in heifers with the introduction of corticotropin]. Izvestiya Timiryazevskoy sel’skokhozyaystvennoy akademii. 1990; 4: 105–114. (In Rus.)

10. Etgen A. Ovarian steroid and growth factor regulation of female reproductive function involves modification of hypothalamic alpha 1-adrenoceptor signaling. Ann. N. Acad. Sci. 2003; 1007: 153–161.

11. Hussain R., El-Etr M., Gaci O. Progesterone and Nestorone facilitate axon remyelination: a role for progesterone receptors. Endocrinology. 2011; 152; 10: 3820–3831.

12. Kelli B., Mermelstein P. Progesterone blocks multiple routes of ion flux. Mol. Cell Neurosci. 2011; 2: 137–141.

13. Tetel M. Nuclear receptor coactivators: essential players for steroid hormone action in the brain and in behavior. J. Neuroendocrinolgy. 2009; 21; 4: 229–237.

14. Toran-Allerand C. Estrogen and the brain: beyond ER-alpha, ER-beta, and 17 beta-estradiol. Ann. N.Y. Acad. Sci. 2005; 1052: 136–144.

15. Ertuev M.M., Semenov U.A. Behavior of the asiatic leopard panthera pardus tulliana in different phases of the estrous cycle. RJOAS. 2017; 4 (64): 281–289.