Hostname: page-component-848d4c4894-nmvwc Total loading time: 0 Render date: 2024-06-28T13:48:23.929Z Has data issue: false hasContentIssue false
  • English
  • Français

Timing of melatonin treatment: differential effects on oestrus and coat growth in goats

Published online by Cambridge University Press:  02 September 2010

I. A. Forsyth ,
F. E. Gebbie  and
J. Arendt
I. A. Forsyth
Affiliation:
Department of Cellular Physiology, The Babraham Institute, Babraham, Cambridge CB2 4AT
F. E. Gebbie
Affiliation:
Department of Cellular Physiology, The Babraham Institute, Babraham, Cambridge CB2 4AT
J. Arendt
Affiliation:
School of Biological Sciences, University of Surrey, Guildford GU2 5XH
Get access

Abstract

To avoid winter scarcity of fresh goat milk, simple methods of advancing the season of kidding would be commercially valuable. A combination of long-day light treatment followed by melatonin is successful but other aspects of seasonality including coat growth are also reset. To investigate whether effects on breeding season and coat growth can be dissociated, British Saanen dairy goats (no. = 30) were randomly allocated to one of six groups. Control goats were untreated. Goats in the other five groups received 2 months of treatment with 20 h light: 4 h darkness (20L: 4D) and were then given 3 mg melatonin orally at 16.00 hfor 2 months. The treatments started on 11 January (group 1), 29 March (group 2), 14 June (group 3), 30 August (group 4) and 8 November (group 5). Weekly blood samples were taken for the measurement of progesterone to monitor ovarian activity and prolactin. Side patches (10 cm ×10 cm) were clipped monthly from alternate sides and weighed to measure coat growth. The onset of ovarian activity was advanced from a median date of 15 November in controls to 24 May in group 1 (P < 0·01), 16 August in group 2 (P < 0·05) and 18 October in group 3 (? < 0·05). Groups 4 and 5 showed no significant change in the onset of oestrus (median onset dates 8 November and 1 November, respectively). Group 1 goats came into season again with controls in November. In all except group 5, treatment interacted with time to affect significantly the growth of the coat. The pattern of coat growth was most altered (P < 0·001) in groups 1 and 2. This was associated with effects on plasma prolactin concentrations of light stimulation and melatonin suppression. Group 1 goats resynchronized with control goats to show a coat of normal weight in the winter following treatment. Division of milking goat herds into spring and autumn kidding groups is, therefore, a practical possibility, but effects on overall milk yield require study.

Keywords

breeding seasoncoatdairyinggoatsmelatoninoestrus
Type
Research Article
Information
Animal Science , Volume 65 , Issue 2 , October 1997 , pp. 267 - 273
Copyright
Copyright © British Society of Animal Science 1997

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

Almeida, O. F. X. and Lincoln, G. A. 1984. Reproductive photorefractoriness in rams and accompanying changes in the pattern of melatonin and prolactin secretion. Biology of Reproduction 30:143–158.CrossRefGoogle ScholarPubMed
Arendt, J. 1995. Melatonin and the mammalian pineal gland. Chapman and Hall, London.Google Scholar
Badhura, L. L. and Goldman, B. D. 1992. Prolactin-dependent seasonal changes in pelage: role of the pineal gland and dopamine. Journal of Experimental Zoology 261: 27–33.CrossRefGoogle Scholar
Buttle, H. L. 1974. Seasonal variation of prolactin in plasma of male goats. Journal of Reproduction and Fertility 37: 95–99.CrossRefGoogle ScholarPubMed
Chemineau, P., Normant, E., Ravault, J.-P. and Thimonier, J. 1986. Induction and persistence of pituitary and ovarian activity in the out-of-season lactating dairy goat after a treatment combining skeleton photoperiod, melatonin and the male effect. Journal of Reproduction and Fertility 78: 497–504.CrossRefGoogle ScholarPubMed
Choy, V. J., Nixon, A. J. and Pearson, A. J. 1995. Localization of receptors for prolactin in ovine skin. Journal of Endocrinology 144:143–151.CrossRefGoogle ScholarPubMed
Curlweis, J. P. 1992. Seasonal prolactin secretion and its role in seasonal reproduction: a review. Reproduction, Fertility and Development 4:1–23.CrossRefGoogle Scholar
Deveson, S. L., Arendt, J. and Forsyth, I. A. 1990. Sensitivity of goats to a light pulse during the night as assessed by suppression of melatonin concentrations in the plasma. Journal of Pineal Research 8:169–177.CrossRefGoogle ScholarPubMed
Deveson, S. L., Arendt, J. and Forsyth, I. A. 1992a. The influence of the pineal gland and melatonin on the reproductive performance of domesticated female ungulates. Animal Reproduction Science 30:113–134.CrossRefGoogle Scholar
Deveson, S. L., Forsyth, I. A. and Arendt, J. 1992b. Induced out-of-season breeding in British Saanen dairy goats: use of artifical photoperiod and/or melatonin administration. Animal Reproduction Science 29:1–15.CrossRefGoogle Scholar
Dicks, P., Russel, A. J. F. and Lincoln, G. A. 1994. The role of prolactin in the reactiviation of hair follicles in relation to moulting in cashmere goats. Journal of Endocrinology 143: 441–448.CrossRefGoogle Scholar
Forsyth, I. A., Barker, P., Keable, S. and Turvey, A. 1994a. Identification of prolactin receptors in hair follicles of the goat using an antipeptide antibody. Journal of Reproduction and Fertility, Abstract Series 14: 14 (abstr.).Google Scholar
Forsyth, I. A., Gebbie, F. E. and Arendt, J. 1994b. Fibre growth and shedding in the dairy goat. European Fine Fibre Network, occasional publication, no. 2, pp. 75–86.Google Scholar
Gebbie, F. E. 1993. Control of seasonal breeding and coat development in the goat. Ph.D. thesis, University of Surrey.Google Scholar
Lincoln, G. A. 1990. Correlation with horns and pelage, but not reproduction, of seasonal cycles in the secretion of prolactin in rams of wild, feral and domesticated breeds of sheep. Journal of Reproduction and Fertility 90: 285–296.CrossRefGoogle Scholar
McNeilly, A. S., Forsyth, I. A. and McNeilly, J. R. 1994. Regulation of post-partum fertility in lactating mammals. In Marshall's physiology of reproduction, 4th edition, vol. 3 (ed. Lamming, G. E.), pp. 1038–1101. Chapman and Hall, London.Google Scholar
Poulton, A. L., English, J., Symons, A. M. and Arendt, J. 1986. Effects of various melatonin treatments on plasma prolactin concentrations in the ewe. Journal of Endocrinology 108: 287–292.CrossRefGoogle ScholarPubMed
Prandi, A., Motta, M., Chiesa, F. and Tamanini, C. 1987. Circannual rhythm of plasma prolactin concentration in the goat. Animal Reproduction Science 17:85–94.CrossRefGoogle Scholar
Salacinski, P. R. P., McLean, C., Sykes, J. E. C, Clement-Jones, V. V. and Lowry, P. J. 1981. Iodination of proteins, glycoproteins and peptides using a solid-phase oxidising agent, l,3,4,6-tetrachloro-3α, 6α-diphenylglycouril (lodogen). Analytical Biochemistry 117: 136–146.CrossRefGoogle Scholar
Sauer, M. J., Foulkes, J. A., Worsfold, A. and Morris, B. A. 1986. Use of progesterone-11-glucuronide-alkaline phosphatase conjugate in a sensitive microtitre-plate enzymeimmunoassay of progesterone in milk and its application to pregnancy testing in cattle. Journal of Reproduction and Fertility 76: 375–391.CrossRefGoogle Scholar
Staples, L. D., McPhee, S., Kennaway, D. J. and Williams, A. H. 1992. The influence of exogenous melatonin on the seasonal patterns of ovulation in sheep. Animal Reproduction Science 30:185–223.CrossRefGoogle Scholar
Tucker, H. A. and Wettemann, R. P. 1976. Effects of ambient temperature and relative humidity on serum prolactin and growth hormone in heifers. Proceedings of the Society for Experimental Biology and Medicine 151: 623–627.CrossRefGoogle ScholarPubMed