Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-22T17:33:44.742Z Has data issue: false hasContentIssue false
  • English
  • Français

Ram-induced oestrus and ovulation in lactating and weaned Corriedale ewes

Published online by Cambridge University Press:  04 November 2009

D. A. Pevsner ,
R. M. Rodríguez Iglesias  and
N. H. Ciccioli
D. A. Pevsner*
Affiliation:
Departamento de Agronomía, Universidad Nacional del Sur, B8000 Bahía Blanca, Argentina Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
R. M. Rodríguez Iglesias
Affiliation:
Departamento de Agronomía, Universidad Nacional del Sur, B8000 Bahía Blanca, Argentina Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
N. H. Ciccioli
Affiliation:
Departamento de Agronomía, Universidad Nacional del Sur, B8000 Bahía Blanca, Argentina
*
†E-mail: [email protected]
Get access

Abstract

Two experiments were conducted in consecutive years in which recently (Experiment 1) or temporarily (Experiment 2) weaned ewes and matched post-partum non-lactating flockmates (DRY) were exposed to a stimulus group of rams and oestrous ewes (10 and 20 in Experiment 1, 20 and 20 in Experiment 2) for 28 days in spring. Lactating ewes (n = 130) in Experiment 1 were isolated from their lambs 4 (W-4), 2 (W-2), 1 (W-1) or 0 (W-0) days in advance and exposed along with a group of 32 DRY flockmates. Lactating ewes in Experiment 2 (n = 230) were allocated to an unreplicated factorial of two levels of temporary weaning before stimulation (B0: control; B24: lambs removed 24 h before stimulation) by four levels of ewe-lamb contact imposed at the start of the stimulation (A0: control; A12, A24 and A36: lamb-ewe separation during the initial 12, 24 or 36 h of exposure); DRY ewes (n = 54) acted as an augmented factorial control. Oestrus (rump marks) and ovulation (laparoscopy on day 5 and on day 28 (Experiment 1) or day 32 (Experiment 2)) were recorded. Ovulation and oestrous responses in Experiment 1 were similar for DRY (90.6% and 55.2%, respectively) and recently weaned ewes (83.8% and 53.7%, respectively). Amongst recently weaned ewes, the immediate ovulation response to the rams and the proportion of ewes still cycling by day 28 tended to be lower (P = 0.065 and P = 0.011) in ewes weaned on the day of ram exposure (71.9% and 54.8% v. 87.8% and 80.0%, respectively). Ovulation rate was lower (P < 0.003) in W-2 ewes (1.3 ± 0.10) than in the other recently weaned groups. In Experiment 2, ovulation (83.3%) and oestrous (68.9%) responses in DRY ewes were higher (P = 0.022 and P = 0.053, respectively) than in lactating ewes (66.2% and 51.0%, respectively). More ewes ovulated (P = 0.036) in B24 (70.5%) than in B0 (61.8%). Ewes having their lambs returned 12 h after the onset of stimulation (A12) had poorer ovulation responses (54.9%) than control ewes (A0, 72.9%, P < 0.05); this was probably associated to lamb restitution after the sunset. Main conclusions were that (i) the presence of the lambs is a depressing factor of both ovulation and oestrous responses to the ram effect in lactating ewes, (ii) the ovulation response of lactating ewes will probably benefit from removing lambs for a period of 24 h before the onset of stimulation, (iii) until additional information becomes available, temporary weaning protocols should be designed avoiding lamb restitution during the night.

Keywords

suckling, ram effect, temporary weaning, pre-exposure weaning, spring rebreeding
Type
Full Paper
Information
animal , Volume 4 , Issue 3 , March 2010 , pp. 472 - 479
Copyright
Copyright © The Animal Consortium 2009

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.)

Footnotes

a

Deceased.

References

Brown, GH 1988. The statistical comparison of reproduction rates for groups of sheep. Australian Journal of Agricultural Research 39, 899–905.CrossRefGoogle Scholar
Chemineau, P, Pellicer-Rubio, MT, Lassoued, N, Khaldi, G, Monniaux, D 2006. Male-induced short oestrous and ovarian cycles in sheep and goats: a working hypotesis. Reproduction, Nutrition, Development 46, 417–429.CrossRefGoogle Scholar
Consortium for Developing a Guide for the Care and Use of Agricultural Animals in Agricultural Research and Teaching 1999. Guide for the care and use of agricultural animals in agricultural research and teaching. University of Illinois Press Urbana, IL, USA.Google Scholar
Ferrería, J, Rodríguez Iglesias, RM, Pevsner, DA, Aba, MA, Rodríguez, MM, Pedrueza, JR 2008. LH response of seasonally anovular Corriedale ewes acutely exposed to rams and oestrous ewes. Animal Reproduction Science 103, 172–178.CrossRefGoogle Scholar
Geytenbeek, PE, Oldham, CM, Gray, SJ 1984. The induction of ovulation in the postpartum ewe. Proceedings of the Australian Society of Animal Production 15, 353–356.Google Scholar
Hamadeh, SK, Abi-Said, M, Tami, F, Barbour, EK 2001. Weaning and the ram-effect on fertility, serum luteinizing hormone and prolactin levels in spring rebreeding of pospartum Awassi ewes. Small Ruminant Research 41, 191–194.CrossRefGoogle Scholar
Hoefler, WC, Hallford, DM 1987. Influence of suckling status and type of birth on serum hormone profiles and return to estrus in early-postpartum spring-lambing ewes. Theriogenology 27, 887–895.CrossRefGoogle Scholar
Jeffries, BC 1961. Body condition scoring and its use in management. Tasmanian Journal of Agriculture 32, 19–21.Google Scholar
Malven, PV 1986. Inhibition of pituitary LH release resulting from endogenous opioid peptides. Domestic Animal Endocrinology 3, 135–142.CrossRefGoogle Scholar
Martin, GB, Cognié, Y, Schirar, A, Nunes Ribeiro, A, Fabre-Nys, C, Thiéry, JC 1985. Diurnal variation in the response of anoestrous ewes to the ram effect. Journal of Reproduction and Fertility 75, 275–284.CrossRefGoogle Scholar
Martin, GB, Kadokawa, H 2006. “Clean, green and ethical” animal production. Case study: reproductive efficiency in small ruminants. Journal of Reproduction and Development 52, 145–152.CrossRefGoogle ScholarPubMed
Martin, GB, Milton, JTB, Davidson, RH, Banchero Hunzicker, GE, Lindsay, DR, Blache, D 2004. Natural methods for increasing reproductive efficiency in small ruminants. Animal Reproduction Science 82–83, 231–246.CrossRefGoogle ScholarPubMed
Martin, GB, Oldham, CM, Cognié, Y, Pearce, DT 1986. The physiological responses of anovulatory ewes to the introduction of rams – a review. Livestock Production Science 15, 219–247.CrossRefGoogle Scholar
MathSoft Inc. 2000. S-PLUS 2000 Professional Edition for Windows, Release 3. MathSoft, Inc., Seattle, WA.Google Scholar
Mauléon, P, Dauzier, L 1965. Variations de la durée de l’anoestrus de lactation chez les brebis de race Ile-de-France. Annales de Biologie Animale, Biochimie et Biophysique 5, 131–141.CrossRefGoogle Scholar
McCullagh, P, Nelder, JA 1989. Generalized linear models, 2nd edition. Chapman & Hall, London.CrossRefGoogle Scholar
McNeilly, AS 1994. Suckling and the control of gonadotropin secretion. In The Physiology of Reproduction, 2nd edition (ed. E Knobil and JD Neill), pp. 1179–1212. Raven Press, NY.Google Scholar
Oldham, CM, Lindsay, DR 1980. Laparoscopy in the ewe: a photographic record of the ovarian activity of ewes experiencing normal or abnormal oestrous cycles. Animal Reproduction Science 3, 119–124.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, 227–236.CrossRefGoogle ScholarPubMed
Restall, BJ 1971. The effect of lamb removal on reproductive activity in Dorset-Horn × Merino ewes after lambing. Journal of Reproduction and Fertility 24, 145–146.CrossRefGoogle ScholarPubMed
Rodríguez Iglesias, RM, Ciccioli, NH, Irazoqui, H 1997. Ram induced reproduction in seasonally anovular Corriedale ewes: MAP doses for oestrus induction, ram percentages and post-mating progestagen supplementation. Animal Science 64, 119–125.CrossRefGoogle Scholar
Rodríguez Iglesias, RM, Ciccioli, NH, Irazoqui, H, Ciccioli, C 1996. Ovulation rate in ewes after single oral glucogenic dosage during a ram-induced follicular phase. Animal Reproduction Science 44, 211–221.CrossRefGoogle Scholar
Rodríguez Iglesias, RM, Ciccioli, NH, Irazoqui, H, Rodríguez, BT 1991. Importance of behavioural stimuli in ram-induced ovulation in seasonally anovular Corriedale ewes. Applied Animal Behaviour Science 30, 323–332.CrossRefGoogle Scholar
Rodríguez Iglesias, RM, Irazoqui, H, Ciccioli, NH, Giglioli, C 1993. Seasonality of oestrus and ovulation rate in Corriedale ewes: repeatabilities and phenotypic correlations. Journal of Agricultural Science, Cambridge 120, 115–119.CrossRefGoogle Scholar
Shevah, Y, Black, WJ, Carr, WR, Land, RB 1974. The effect of lactation on the resumption of reproductive activity and the preovulatory release of LH in Finn × Dorset ewes. Journal of Reproduction and Fertility 38, 369–378.CrossRefGoogle ScholarPubMed
Signoret, JP, Fulkerson, WJ, Lindsay, DR 1982. Effectiveness of testosterone-treated wethers and ewes as teasers. Applied Animal Ethology 9, 37–45.CrossRefGoogle Scholar
Silva, L, Ungerfeld, R 2006. Reproductive response in suckling Corriedale ewes to the ram effect during the non-breeding season: effect of postpartum condition and the use of medroxyprogesterone priming. Tropical Animal Health and Production 38, 365–369.CrossRefGoogle Scholar
Tukey, JW 1949. One degree of freedom for non-additivity. Biometrics 5, 232–242.CrossRefGoogle Scholar
Ungerfeld, R 2007. Socio-sexual signalling and gonadal function: opportunities for reproductive management in domestic ruminants. Society of Reproduction and Fertility Supplement 64, 207–221.Google ScholarPubMed
Williams, GL 1990. Suckling as a regulator of postpartum rebreeding in cattle: a review. Journal of Animal Science 68, 831–852.CrossRefGoogle ScholarPubMed
Wright, PJ, Geytenbeek, PE, Clarke, IJ, Hoskinson, RM 1989. The efficacy of ram introduction, GnRH administration, and immunisation against androstenedione and oestrone for the induction of oestrus and ovulation in anoestrous postpartum ewes. Animal Reproduction Science 21, 237–247.CrossRefGoogle Scholar