Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-24T09:15:31.427Z Has data issue: false hasContentIssue false

New insights into the influence of breed and time of the year on the response of ewes to the ‘ram effect’

Published online by Cambridge University Press:  27 May 2011

A. Chanvallon
Affiliation:
Centre Interrégional d'Information et de Recherche en Production Ovine, Site expérimental du Mourier, 87800 St Priest Ligoure, France UMR 6175 INRA Physiologie de la Reproduction et des Comportements – CNRS – Université de Tours – Haras Nationaux, 37380 Nouzilly, France
L. Sagot
Affiliation:
Institut de l'Elevage, 149 rue de Bercy, 75595 Paris Cedex 12, France
E. Pottier
Affiliation:
Centre Interrégional d'Information et de Recherche en Production Ovine, Site expérimental du Mourier, 87800 St Priest Ligoure, France Institut de l'Elevage, 149 rue de Bercy, 75595 Paris Cedex 12, France
N. Debus
Affiliation:
UMR868 “Elevage des Ruminants en Régions Chaudes”, 2 Place Viala, 34060 Montpellier Cedex 1, France
D. François
Affiliation:
INRA SAGA, Chemin de Borde-Rouge Auzeville, BP 52627, 31326 Castanet Tolosan, France
T. Fassier
Affiliation:
INRA Bourges, Domaine de la Sapinière, 18390 Osmoy, France
R. J. Scaramuzzi
Affiliation:
UMR 6175 INRA Physiologie de la Reproduction et des Comportements – CNRS – Université de Tours – Haras Nationaux, 37380 Nouzilly, France Department of Veterinary Basic Sciences, The Royal Veterinary College, Hawkshead Lane, North Mimms, Hertfordshire AL9 7TA, UK
C. Fabre-Nys*
Affiliation:
UMR 6175 INRA Physiologie de la Reproduction et des Comportements – CNRS – Université de Tours – Haras Nationaux, 37380 Nouzilly, France
*
Get access

Abstract

Exposure of anoestrous ewes to rams induces an increase in LH secretion, eventually leading to ovulation. This technique therefore is an effective, low-cost and hormone-free way of mating sheep outside the breeding season. However, the use of this technique is limited by the variability of the ewes’ responses. In this study, our objective was to understand more completely the origins of this variability and to determine the relative roles of breed, the point in time during anoestrus and the depth of anoestrus on the response to the ‘ram effect’. In the first experiment, the pattern of anoestrus on the basis of the concentration of progesterone determined weekly, was determined in four breeds including two less seasonal (Mérinos d'Arles and Romane), one highly seasonal (Mouton Vendéen) and one intermediate (Île-de-France) breeds. Anoestrus was longer and deeper in Mouton Vendéen and Île-de-France than in Romane or Mérinos d'Arles. In the second experiment, we used the same four breeds and tested their hypophyseal response to a challenge with a single dose of 75 ng gonadotrophin-releasing hormone (GnRH) in early, mid and late anoestrus, and then we examined their endocrine and ovarian responses to the ‘ram effect’. Most (97%) ewes responded to GnRH and most (93%) showed a short-term increase in LH pulsatility following the ‘ram effect’. The responses in both cases were higher in females that went on to ovulate, suggesting that the magnitude of the hypophyseal response to a GnRH challenge could be a predictor of the response to the ‘ram effect’. As previously observed, the best ovarian response was in Mérinos d'Arles at the end of anoestrus. However, there was no relationship between the proportion of females in the flock showing spontaneous ovulation and the response to the ‘ram effect’ of anoestrous ewes from the same flock.

Type
Full Paper
Copyright
Copyright © The Animal Consortium 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bocquier, F, Theriez, M, Prache, S, Brelurut, A 1988. Alimentation des ovins. In Alimentation des bovins, ovins et caprins (ed. R Jarrige), pp. 249280. INRA, Paris, France.Google Scholar
Canépa, S, Laine, AL, Bluteau, A, Fagu, C, Flon, C, Monniaux, D 2008. Validation d'une méthode immunoenzymatique pour le dosage de la progestérone dans le plasma des ovins et des bovins. Cahier des Techniques de l'Inra 64, 1930.Google Scholar
Caraty, A, Delaleu, B, Chesneau, D, Fabre-Nys, C 2002. Sequential role of E2 and GnRH for the expression of estrous behavior in ewes. Endocrinology 143, 139145.CrossRefGoogle ScholarPubMed
Caraty, A, Smith, JT, Lomet, D, Ben Saïd, S, Morrissey, A, Cognie, J, Doughton, B, Baril, G, Briant, C, Clarke, IJ 2007. Kisspeptin synchronizes preovulatory surges in cyclical ewes and causes ovulation in seasonally acyclic ewes. Endocrinology 148, 52585267.CrossRefGoogle ScholarPubMed
Chanvallon, A, Sagot, L, Pottier, E, Scaramuzzi, RJ, Fabre-Nys, C 2009. Interactions among seasonality of reproduction, genotype and the ram effect. Archiva Zootechnica 12, 7381.Google Scholar
Chanvallon, A, Blache, D, Chadwick, A, Esmaili, T, Hawken, PA, Martin, GB, Viñoles, C, Fabre-Nys, C 2010. Sexual experience and temperament affect the response of Merino ewes to the ram effect during the anoestrous season. Animal Reproduction Science 119, 205211.Google Scholar
Chemineau, P, Pellicer-Rubio, MT, Lassoued, N, Khaldi, G, Monniaux, D 2006. Male-induced short oestrus and ovarian cycles in sheep and goats: a working hypothesis. Reproduction Nutrition Development 46, 417429.Google Scholar
Ciechanowska, M, Lapot, M, Malewski, T, Mateusiak, K, Misztal, T, Przekop, F 2008. Expression of the GnRH and GnRH receptor (GnRH-R) genes in the hypothalamus and of the GnRH-R gene in the anterior pituitary gland of anestrous and luteal phase ewes. Animal Reproduction Science 108, 345355.Google Scholar
Cushwa, WT, Bradford, GE, Stabenfeldt, GH, Berger, YM, Dally, MR 1992. Ram influence on ovarian and sexual activity in anoestrous ewes: effects of isolation of ewes before joining and date of ram introduction. Journal of Animal Science 70, 11951200.CrossRefGoogle Scholar
Faure, MO, Nicol, L, Fabre, S, Fontaine, J, Mohoric, N, McNeilly, A, Taragnat, C 2005. BMP-4 inhibits follicle-stimulating hormone secretion in ewe pituitary. Journal of Endocrinology 186, 109121.Google Scholar
Goodman, RL, Karsch, FJ 1981. A critique of the evidence on the importance of steroid feedback to seasonal changes in gonadotrophin secretion. Journal of Reproduction and Fertility Supplement 30, 113.Google Scholar
Lindsay, DR, Signoret, JP 1980. Influence of behaviour on reproduction. Proceedings of the 9th International Congress on Animal Reproduction and Artificial Insemination 1, 8392.Google Scholar
Martin, GB, Oldham, CM, Lindsay, DR 1980. Increased plasma LH levels in seasonally anovular Merino ewes following the introduction of rams. Animal Reproduction Science 3, 125132.CrossRefGoogle Scholar
Martin, GB, Oldham, CM, Cognié, Y, Pearce, DL 1986. The physiological responses of anovulatort ewes to the introduction of rams – a review. Livestock Production Science 15, 219247.CrossRefGoogle Scholar
McLeod, BJ, Haresign, W, Lamming, GE 1982. Response of seasonally anoestrous ewes to small-dose multiple injections of Gn-RH with and without progesterone pretreatment. Journal of Reproduction and Fertility 65, 223230.CrossRefGoogle ScholarPubMed
Minton, JE, Coppinger, TR, Spaeth, CW, Martin, LC 1991. Poor reproductive response of anoestrous Suffolk ewes to ram exposure is not due to failure to secrete luteinising hormone acutely. Journal of Animal Science 69, 33143320.CrossRefGoogle Scholar
Nugent, RA, Notter, DR 1990. Effect of cohabitation with white-faced ewes on estrous activity of Hampshire and Suffolk ewes exposed to rams in June. Journal of Animal Science 68, 15131519.CrossRefGoogle ScholarPubMed
O'Callaghan, D, Donovan, A, Sunderland, SJ, Boland, MP, Roche, JF 1994. Effect of the presence of male and female flock mates on reproductive activity in ewes. Journal of Reproduction and Fertility 100, 497503.CrossRefGoogle Scholar
Oldham, CM 1980. A study of sexual and ovarian activity in Merino sheep. PhD, Western Australia University.Google Scholar
Oldham, CM, Cognié, Y 1980. Do ewes continue to cycle after teasing? Proceeding of the Australian Society of Animal Production 13, 8285.Google Scholar
Oldham, CM, Martin, GB 1978. Stimulation of the seasonally anovular Merinos ewes by rams. II. Premature regression of ram-induced corpora lutea. Animal Reproduction Science 1, 291295.CrossRefGoogle Scholar
Oldham, CM, Martin, GB, Knight, TW 1978. Stimulation of the seasonally anovular Merinos ewes by rams. I. Time from introduction of the rams to the preovulatory surge and ovulation. Animal Reproduction Science 1, 283290.CrossRefGoogle Scholar
Pearce, DT, Martin, GB, Oldham, CM 1985. Corpora lutea with a short life-span induced by rams in seasonally anovulatory ewes are prevented by progesterone delaying the preovulatory surge of LH. Journal of Reproduction and Fertility 75, 7984.CrossRefGoogle Scholar
Poindron, P, Cognie, Y, Gayerie, F, Orgeur, P, Oldham, CM, Ravault, JP 1980. Changes in gonadotrophins and prolactin levels in isolated (seasonally or lactationally) anovular ewes associated with ovulation caused by the introduction of rams. Physiology and Behavior 25, 227236.Google Scholar
Restall, BJ, Restall, H, Walkden-Brown, SW 1995. The induction of ovulation in anovulatory goats by oestrous females. Animal Reproduction Science 40, 299303.Google Scholar
Rosa, HJD, Bryant, MJ 2002. The ram effect as a way of modifying the reproductive activity in the ewe: a review. Small Ruminant Research 45, 116.CrossRefGoogle Scholar
Russel, AJF, Donney, JM, Gunn, RG 1969. Subjective assessment of body fat in live sheep. Journal of Agricultural Science 72, 451454.CrossRefGoogle Scholar
Sakurai, H, Adams, BM, Adams, TE 1992. Pattern of gonadotropin-releasing hormone (GnRH)-like stimuli sufficient to induce follicular growth and ovulation in ewes passively immunized against GnRH. Biology of Reproduction 47, 177184.Google Scholar
Thimonier, J, Mauléon, P 1969. Variations saisonnières du comportement d'oestrus et des activités ovarienne et hypophysaire chez les ovins. Annals of Biology, Animal Biochemistry and Biophysics 9, 233250.Google Scholar
Thimonier, J, Cognié, Y, Lassoued, N, Khaldi, G 2000. L'effet mâle chez les ovins: une technique actuelle de maîtrise de la reproduction. INRA Productions Animales 13, 223231.Google Scholar
Tournadre, H, Bocquier, F, Petit, M, Thimonier, J, Benoit, M 2002. Efficacité de l'effet bélier chez la brebis limousine à différents moments de l'anoestrus saisonnier et selon la durée de l'intervalle tarissement-mise en lutte. Conference at the 9e Rencontres Recherches Ruminants, Paris, France, pp. 143–146.Google Scholar
Underwood, EJ, Shier, FL, Davenport, N 1944. Studies in sheep husbandry in WA. The breeding season of Merino, crossbreed and British breed ewes in agricultural districts. Journal of Agriculture of Western Australia 11, 135143.Google Scholar
Ungerfeld, R, Forsberg, M, Rubianes, E 2004. Overview of the response of anoestrus ewes to the ram effect. Reproduction, Fertility and Development 16, 479490.CrossRefGoogle Scholar
Ungerfeld, R, Pinczak, A, Forsberg, M, Rubianes, E 2002. Ovarian responses of anestrous ewes to the “ram effect”. Canadian Journal of Animal Science 82, 599602.CrossRefGoogle Scholar
Zarco, L, Rodriguez, EF, Angulo, MRB, Valencia, J 1995. Female to female stimulation of ovarian activity in the ewe. Animal Reproduction Science 39, 251258.Google Scholar