Endocrine and ovarian changes in response to the ram effect in medroxyprogesterone acetate-primed corriedale ewes during the breeding and nonbreeding season

Acta Veterinaria Scandinavica

Volumn 46, Issue 1-2, 2005, Pages 33-44

  Ungerfeld, R ^a,b   Carbajal, B ^a   Rubianes, E ^a   Forsberg, M ^b  

^a UNIVERSIDAD DE LA REPÚBLICA   (Uruguay)

^b SWEDISH UNIVERSITY OF AGRICULTURAL SCIENCES   (Sweden)

Author keywords

Anestrous depth; Ewe; Gonadotrophin; Ram stimulus; Teaser rams

Indexed keywords

OVIS;

CONTRACEPTIVE AGENT; ESTRADIOL; FOLLITROPIN; LUTEINIZING HORMONE; MEDROXYPROGESTERONE ACETATE;

ANIMAL; ARTICLE; BLOOD; BREEDING; DRUG EFFECT; ECHOGRAPHY; ESTRUS; FEMALE; MALE; OVARY; PREGNANCY; SHEEP;

ANIMALS; BREEDING; CONTRACEPTIVE AGENTS, FEMALE; ESTRADIOL; ESTRUS; FEMALE; FOLLICLE STIMULATING HORMONE; LUTEINIZING HORMONE; MALE; MEDROXYPROGESTERONE 17-ACETATE; OVARY; PREGNANCY; SHEEP;

EID: 23944447146     PISSN: 0044605X     EISSN: None     Source Type: Journal    
DOI: None     Document Type: Article

References (29)

1. Ann Lai SC: Behavioral enhancement of ewe lamb reproduction through use of the "ram effect". Master in Science Thesis. Faculty of the Graduate School of Cornell University, USA, 1988, 108 p.
2. Baird DT, Land RB, Scaramuzzi RJ, Wheeler AG: Endocrine changes associated with luteal regression in the ewe: the secretion of ovarian oestradiol, progesterone, and androstenedione and uterine prostaglandin F2a throughout the oestrous cycle. J. Endocrinol. 1976, 69, 275-286.
3. Evans ACO, Duffy P, Crosby TF, Hawken PA, Boland MP, Beard AP: Effect of ram exposure at the end of progesterone treatment on estrus synchronisation and fertility during the breeding season in ewes. Anim. Reprod. Sci. 2004, 84, 349-358.
4. Evans ACO, Duffy P, Quinn KM, Beard AP, Crosby TF, Boland MP: Introduction of a ram three days before progestagen sponge withdrawal decreases fertility and alters the timing of oestrus, the LH surge and ovulation in ewes. Proc. Sixth International Symposium on Reproduction in Domestic Ruminants, Crieff, Scotland, August 14-17, 2002, p A22.
5. Forsberg M, Tagle R, Madej A, Molina JR, Carlsson M-A: Radioimmunoassay of bovine, ovine and porcine LH with a monoclonal antibody and a human tracer. Acta Vet. Scand. 1993, 34, 255-262.
6. Geytenbeek PE, Oldham CM, Gray SJ: The induction of ovulation in the postpartum ewe. Proc. Aust. Soc. Anim. Prod. 1984, 15, 353-356.
7. Goodman RL, Pickover SM, Karsch FJ: Ovarian feedback control of follicle-stimulating hormone in the ewe: evidence for selective suppression. Endocrinology 1981, 108, 772-777.
8. Hunter GL, Belonje PC, Van Niekerk CH: Synchronized mating and lambing in spring-bred Merino sheep: the use of progestogen-impregnated intravaginal sponges and teaser rams. Agroanimalia 1971, 3, 133-140.
9. Lucidi P, Barboni B, Mattioli M: Ram-induced ovulation to improve artificial insemination efficiency with frozen semen in sheep. Theriogenology 2001, 55, 1797-1805.
10. Martin, G.B., Cognié, Y., Schirar, A., Nunes-Ribeiro, A., Fabre-Nys, C. & Thiéry, J.-C: Diurnal variation in the response of anoestrous ewes to the ram effect. J. Reprod. Fertil. 1985, 75, 275-284.
11. Martin GB, Oldham CM, Cognie Y, Pearce D: The physiological responses of anovulatory ewes to the introduction of rams - a review. Livest. Prod. Sci. 1986, 75, 219-247.
12. Martin GB, Scaramuzzi RJ: The induction of oestrus and ovulation in seasonally anovular ewes by exposure to rams. J. Steroid. Biochem. 1983, 19, 869-875.
13. Martin GB, Scaramuzzi RJ, Lindsay DR: Induction of ovulation in seasonally anovular ewes by the introduction of rams: effects of progesterone and active immunization against androstenedione. Aust. J. Biol. Sci. 1981, 34, 569-575.
14. Meikle A: Reproductive endocrinology of prepubertal and anestrous ewes. Regulation of uterine sex steroid receptors by ovarian hormones and effects of estradiol on gonadotropin secretion and follicular growth. Ph.D. Thesis, Swedish University of Agricultural Sciences, Uppsala, Sweden, 2001, 51 p.
15. Oldham CM, Gray SJ: The 'ram effect' will advance puberty in 9-10 month old Merino ewes independent of their season of birth. Proc. Aust. Soc. Anim. Prod. 1984, 15, 727.
16. Oldham CM, Martin GB, Knight TW: Stimulation of seasonally anovular Merino ewes by rams. I. Time from introduction of the rams to the preovulatory LH surge and ovulation. Anim. Reprod. Sci. 1978/1979, 1, 283-290.
17. Oussaid B, Cognie Y, Mariana JC: Ovarian stimulation following repeated injections of LH or LH + FSH in Ile-de-France sheep in early and mid-seasonal anoestrus. Anim. Reprod. Sci. 1993, 31, 83-98.
18. Pearce DT, Oldham CM: Ram effect in the breeding season. Proc. Aust. Soc. Rep. Biol., Canberra, Australia, September 4-7, 1983, p 49.
19. Poindron P, Cognie Y, Gayerie F, Orgeur P, Oldham CM, Ravault JP: Changes in gonadotrophins and prolactin levels in isolated (seasonally or lactationally) anovular ewes associated with ovulation caused by introduction of rams. Phys. Behav. 1980, 25, 227-236.
20. Restall BJ: Seasonal variation in reproductive activity in Australian goats. Anim. Reprod. Sci. 1992, 27, 305-318.
21. Rodríguez Iglesias RM, Ciccioli N, Irazoqui H, Rodriguez BT: Importance of behavioural stimuli in ram-induced ovulation in seasonally anovular Corriedale ewes. Appl. Anim. Behav. Sci. 1991, 30, 323-332.
22. SAS: 1996. Statistical Analysis Systems, Version 6.12.
23. Signoret JP, Fulkerson WJ, Lindsay DR: Effectiveness of testosterone-treated wethers and ewes as teasers. Appl. Anim. Ethol. 1982, 9, 37-45.
24. Ungerfeld R, Pinczak A, Forsberg M, Rubianes E: Response of Corriedale ewes to the "ram effect" after primings with medroxyprogesterone, fluorogestone, or progesterone in the non-breeding season. Acta Vet. Scand. 1999, 40, 299-305.
25. Ungerfeld R, Pinczak A, Forsberg M, Rubianes E: Parámetros para determinar la profundidad del anestro estacional en la oveja. [Parameters to determine anestrus depth in sheep.] Quinta Reunión Latinoamericana de Cátedras de Fisiología Veterinaria, La Plata, Argentina, 14-15 de diciembre, 2000. [Fifth Latin American Veterinary Physiology Departments Meeting, La Plata, Argentina, December 14-15, 2000.]
26. Ungerfeld R, Pinczak A, Forsberg M, Rubianes E: Ovarian and endocrine responses of Corriedale ewes to ram effect in the non-breeding season. Can. J. Anim. Sci. 2002, 82, 599-602.
27. Ungerfeld R, Rubianes E: Estrous response to ram effect in Corriedale ewes primed with medroxyprogesterone during the breeding season. Small Rum. Res. 1999, 32, 89-91.
28. Ungerfeld R, Suárez G, Carbajal B, Silva L, Laca M, Forsberg M, Rubianes E: Medroxyprogesterone primings and response to the ram effect in Corriedale ewes during the non-breeding season. Theriogenology 2003, 60, 35-45.
29. Walkden-Brown SW, Martin GB, Restall BJ: Role of male-female interaction in regulating reproduction in sheep and goats. J. Reprod. Fertil. (Suppl.) 1999, 52, 243-257.