Efecto del estrés provocado por la ecografía sobre las concentraciones plasmáticas de cortisol y progesterona (P4) durante el ciclo estral en ovejas

Abstract

ABSTRACT: The primary purpose of this study was to observe the effects of repeated transrectal ultrassonography on plasmatic concentrations of cortisol and progesterone (P4) in ewes during estrous cycle. Seven Bergamasca ewes (2-5 years of age), received two luteolytic doses of cloprostenol at 7 day intervals during the breeding season. Estrous was detected using a vasectomized ram. Ovaries were examined daily using transrectal ultrassonography. The ewes were studied starting one day before the second PGF2α injection until 10 days after ovulation (day 0 = ovulation). Jugular vein blood samples were collected daily and after ultrassonography for plasma cortisol and P4 measurement. There was no effect of the repeated transrectal ultrassonography on plasma concentrations of cortisol. However, analysis of variance indicated that cortisol concentrations varied over time. Higher plasma concentrations were detected after ultrassonography on day-1 (1.74±0.76 µg/dL) and day-0 (2.9±0.76 µg/dL). Rise in plasma cortisol during the first days of stress reflected the emotional reaction to the stressor. However, mean P4 concentrations were unaffected by transrectal ultrassonography on day-1 (1.28±0.32 ng/mL) and day-2 (1.53±0.32 ng/ mL) when compared to those before ultrassonography on the same days (0.95±0.32 and 1.10±0.31 ng/mL, respectively). In summary, endocrine responses of cortisol and P4 plasma concentration to repeated transrectal ultrassonography were unaffected during follicular and early luteal phase in ewes. 

Keywords:

ACTH

corticotropina

estro

ovulación

reproducción

ACTH

corticotropin

estrous

ovulation

reproduction

References

Alila, H.W. & Dowd, J.P. The control of the corpus luteum function. In: Milligan, S.R. (Ed.). Review of reproductive biology. Oxford: Oxford University Press, 1991. p.203-237.

Barglow, P.; Hatcher, R.; Berndt, D. et al. Psychosocial childbearing stress and metabolic control in pregnant diabetics. Journal Nervous Mental Disease, p.615-620, 1985.

Barrett, D.M.W.; Bartlewski, P.M.; Batista-Arteaga, M. et al. Ultrasound and endocrine evaluation of the ovarian response to a single dose of 500 IU of eCG following a 12-day treatment with progestogen-releasing intravaginal sponges in the breeding and nonbreeding season in ewes. Theriogenology, v.61, p.311-327, 2004.

Bartlewski, P.M.; Beard, A.P.; Cook, S.J. et al. Ovarian antral follicular dynamics and their relationships with endocrine variables throughout the oestrous cycle in breeds of sheep differing in prolificacy. Journal of Reproduction and Fertility, v.115, p.111-124, 1999.

Battaglia, D.F.; Beaver, A.B.; Harris, T.G.; Tanhehco, E.; Viguie, C. & Karsch, F.J. Endotoxin disrupts the estradiol-induced luteinizing hormone surge: interference with estradiol signal reading, not surge release. Endocrinology, v.140, p.2471- 2479, 1999.

Battaglia, D.F.; Krasa, H.B.; Padmanabhan, V. et al. Endocrine alterations that underlie endotoxininduced disruption of the follicular phase in ewes. Biology of Reproduction, v.62, p.45-53, 2000.

Bolaños, J.M.; Molina, J.R. & Forsberg, M. Effect of blood sampling and administration of ACTH on cortisol and progesterone levels in ovariectomized zebu cows (Bos indicus). Acta Veterinaria Scandinavica, v.38, p.1-7, 1997.

Breen, K.M. & Karsch, F.J. New insights regarding glucocorticoids, stress and gonodotropin suppression. Neuroendocrinology, p.233-245, 2006.

Buckingham, J.C.; Cowell, A-M.; Gillies, G.E. et al. The neuroendocrine System: Anatomy, Physiology and responses to Stress. In: Buckingham, J.C.; Gillies, G.E. & Cowell, A.M. (Ed.). Stress, Stress Hormones and the Immune System. Chichester: John Wiley & Sons, Ltd., 1997. p.9-47.

Burris, T.P. Progestins. In: Knobil, E. & Neill, J.D. (Ed.). Encyclopedia of Reproduction. San Diego: Academic Press, 1998. p.23-30.

Chamley, W.A.; Buckmaster, J.M.; Cain, M.D. et al. The effect of prostaglandin F2 alpha on progesterone, oestradiol and luteinizing hormone secretion in sheep with ovarian transplant. Journal Endocrinology, v.55, p.253-263, 1972. Dobson, H. & Smith, R.F. Stress and subfertility. Reproduction Domestic Animal, v.33, p.107- 111, 1998.

Dobson, H. & Smith, R.F. What is tress, and how does it affect reproduction? Animal Reproduction Science, v.60-61, p.743-752, 2000.

Doney, J.M; Gunn, R.G.; Smith, W.F. et al. Effects of pre-mating environmental stress, ACTH, cortisone acetate or metyrapone on estrus and ovulation in sheep. Journal Agricultural Science, v.87, p.127-132, 1976.

Ginther, O.J. & Kot, K. Follicular dynamics during the ovulatory season in goats. Theriogenology, v.42, p.987-1001, 1994.

Goldstein, R.E.; Cherrington, A.D.; Reed, G.W. et al. Effects of chronic hypercortisolemia on carbohydrate metabolism during insulin deficiency. American Journal of Physiology, p.E618–E627, 1994.

Letelier, C.A.; Contreras-Solis, I.; García-Fernández, R.A. et al. Ovarian folicular dynamics and plasma steroid concentrations are not significantly different in ewes given intravaginal sponges containing either 20 or 40 mg of fluorogestone acetate. Theriogenology, v.71, p.676-682, 2009.

López-Sebastian, A.; González-Bulnes, A.; Carrizosa, J.A. et al. New estrus synchronization and artificial insemination protocol for goats based on male exposure, progesterone and cloprostenol during the non-breeding season. Theriogenology, v.68, p.1081-1087, 2007.

Menchaca, A. & Rubianes, E. New treatments associated with timed artificial insemination in small ruminants. Reproduction Fertility and Development, v.16, p.403-413, 2004.

Moberg, G.P. Adrenal-pituitary interactions: effect on reproduction. In: 10th International Congress on Animal Reproduction and AI – 1984, Illinois. Proceedings … ICAR; 1984. p.1-29.

Morberg, G.P. Influence of the adrenal axis upon the gonads. Oxford Review Reproduction, v.9, p.456-96, 1987.

Niswender, G.D.; Farin, C.E.; Gamboni, F. et al. Role of luteinizing hormone in regulating luteal function in ruminants. Journal of Animal Science (Suppl), v.62, p.1-13, 1986.

Oba, E.; Uribe-Velásquez, L.F.; Villa-Velásquez, H. et al. Effect of stress due ultrassonography on plasma cortisol and progesterone (P4 ) concentrations in Ewes. In: 14th International Congress on Animal Reproduction – 2000, Suecia. Proceedings … ICAR; 2000. p.263.

Pacak, K., and Palkovits, M.. Stressor specificity of central neuroendocrine responses: implications for stress-related disorders. Endocrinological Reviews, p.502-548, 2001.

Pierce, B.N.; Clarke, I.J.; Turner, A.I. et al. Cortisol disrupts the ability of oestradiol-17β to induce surge in ovariectomized ewes. Domestic Animal Endocrinology, v.36, p.202-208, 2009.

Phogat, J.B., Smith, R.F. & Dobson, H. Effect of transport on pituitary responsiveness to exogenous pulsatile GnRH and oestradiolinduced LH release in intact ewes. Journal Reproduction and Fertility, p. 9-18, 1999.

Ravindra, J.P.; Rawlings, N.C.; Evans, A.C.O. et al. Ultrasonographic study of ovarian follicular dynamics in ewes during the oestrous cycle. Journal of Reproduction and Fertility, v.101, p.501-509, 1994.

Rawlings, N.C. & Cook, S.J. The effects of acclimation to confinement on gonadotrophin and cortisol secretion during the estrous cycle of the ewe. Canadian Journal of Animal Science, v.71, p.327-332, 1991.

Rivier, C. & Rivest, S. Effect of stress on activity of the hypothalamic-pituitary-gonadal axis – peripheral and central mechanisms. Biology of Reproduction, v.45, p.523-532, 1991.

Robinson, J.E.; Kendrick, K.M. & Lambart, C.E. Changes in the release of gamma-aminobutyricacid and catecholamines in the preoptic septal area prior to and during the preovulatory surge in LH in the ewe. Journal of Neuroendocrinology, p.393-399, 1991.

SAS, SAS/STAT User´s Guide, ed. 6.12: SAS institute, Cary, NC, USA, 1996. Sapolsky, R.M.; Romero, M.L. & Munck, A.U. How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions. Endocrinological Reviews, p. 55-89, 2000.

Saifullizam, A.K.; Routly, J.E.; Smith, R.F. et al. Effect of insulin on the relationship of estrous behaviors to estradiol and LH surges in intact ewes. Physiology Behavioural, v.99, 555-561, 2010.

Schrick, F.N.; Surface, R.A.; Pritchard, J.Y. et al. Ovarian structures during the oestrous cycle and early pregnancy in ewes. Biology of Reproduction, v.49, p.1133-1140, 1993.

Sheldrick, E.L. & Flint, A.P. Endocrine control of uterine oxytocin receptors in the ewe. Journal Endocrinology, v.106, p.249-258, 1985.

Smith, R.F. & Dobson, H. Hormonal interactions within the hypothalamus and pituitary with respect to stress and reproduction in sheep. Domestic Animal Endocrinology, v.23, p.75- 85, 2002.Smith, R.F.;

Ghuman, S.P.S.; Evans, N.P. et al. Stress and control of LH secretion in the ewe. Reproduction (Suppl. 61), p.267-282, 2003.

Tsuma, V.T.; Einarson, S.; Madej, A. et al. Plasma levels of cortisol and progesterone after ACTH administration in pregnant and lactating primiparous sows. Acta VeterinariaScandinavica, v.39, p.71-76, 1998.

Uribe-Velásquez, L.F.; Oba, E. & Brasil, L.H.A. Concentrações plasmáticas de cortisol, hormônios tiroídeanos, metabólitos lipídicos e temperatura corporal de cabras Alpinas submetidas ao estresse térmico. Revista Brasileira de Zootecnia, v.27, p.1123-1130, 1998.

Uribe-Velásquez, L.F.; Oba, E. & Souza, M.I.L. Población folicular y concentraciones plasmáticas de progesterona (P4 ) en ovejas sometidas a diferentes protocolos de sincronización. Archivos de Medicina Veterinaria, v.40, p.83- 88, 2008a.

Uribe-Velásquez, L.F.; Oba, E.; Souza, M.I.L. Efeitos da progesterona exógena sobre o desenvolvimento folicular em ovelhas. Arquivos Brasileiro de Medicina Veterinaria, v.60, p.58- 65, 2008b.

Uribe-Velásquez, L.F.; Souza, M.I.L. & Osorio, J.H. Resposta ovariana de cabras submetidas a implantes de progesterona seguidos de aplicações de gonadotrofina coriônica equina. Revista Brasileira de Zootecnia, v.39, p.1214- 1222, 2010.

Vellucci, S.V. The autonomic and behavioural responses to stress. In: Buckingham, J.C.; Gillies, G.E. & Cowell, A.M. (Ed.). Stress, Stress Hormones and the Immune System. Chichester: John Wiley & Sons, Ltd., 1997. p.49-70.