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Can audio–visual or visual stimuli from a prospective mate stimulate a reproductive neuroendocrine response in sheep?

Published online by Cambridge University Press:  01 May 2009

P. A. R. Hawken ,
T. Esmaili ,
V. Scanlan ,
D. Blache  and
G. B. Martin
P. A. R. Hawken*
Affiliation:
UWA Institute of Agriculture (Animal Production), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
T. Esmaili
Affiliation:
UWA Institute of Agriculture (Animal Production), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
V. Scanlan
Affiliation:
UWA Institute of Agriculture (Animal Production), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
D. Blache
Affiliation:
UWA Institute of Agriculture (Animal Production), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
G. B. Martin
Affiliation:
UWA Institute of Agriculture (Animal Production), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
*
E-mail: phawken@animals.uwa.edu.au
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Abstract

Stimuli from a prospective mate increase the secretion of luteinising hormone (LH) in sheep. This ‘male effect’ in ewes and ‘female effect’ effect in rams is predominantly mediated by olfactory signals, though it is thought that non-olfactory signals play synergistic or substitutive roles. In this study, we tested whether exposure to visual or audio–visual stimuli from a prospective mate would stimulate an increase in LH secretion in ewes (Experiment 1) and rams (Experiment 2). In Experiment 1, groups of eight Merino ewes were exposed to one of three stimuli midway through a frequent blood-sampling regimen: full ram contact, still images of rams, a video of ewes and rams mating. Control ewes (n = 8) were completely isolated from rams. Exposure to still images of rams appeared to stimulate an increase in mean LH concentrations (P < 0.05) and tended to increase LH pulse frequency (P < 0.1), but the response was significantly smaller than that observed in ewes exposed to rams (P < 0.01). Audio–visual stimuli had no effect on any parameters of LH secretion (P > 0.1). In Experiment 2, Merino rams were allocated to either an Exposure (n = 7) or a Control (n = 7) group. Exposure rams underwent two exposure periods midway through a frequent blood-sampling regimen; exposure to still images of ewes and audio recorded during mating of ewes and rams (audio–visual exposure); exposure to oestrous ewes (ewe exposure). Control rams were sampled at the same frequency but remained isolated from ewe stimuli. Exposure of rams to the audio–visual stimuli did not affect any parameters of LH secretion (P > 0.1). In contrast, exposure to oestrous ewes increased LH pulse frequency (P < 0.05) and advanced the onset of the next LH pulse (P < 0.05). In conclusion, visual signals appear to be involved in eliciting the neuroendocrine response of ewes to rams and are of greater importance to this phenomenon in ewes (male effect) than rams (female effect). However, overall the visual and audio–visual signals used in this study were far less effective than stimulus animals, suggesting that these stimuli are less important than olfactory signals, or a combination of olfactory and audio–visual signals.

Keywords

female effectluteinising hormonemale effectnon-olfactoryvisual
Type
Full Paper
Information
animal , Volume 3 , Issue 5 , May 2009 , pp. 690 - 696
Copyright
Copyright © The Animal Consortium 2009

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References

Banks, EM 1964. Some aspects of sexual behaviour in domestic sheep, Ovis aries. Behavior 23, 249–279.CrossRefGoogle Scholar
Cohen-Tannoudji, J, Locatelli, A, Signoret, JP 1986. Non-pheromonal stimulation by the male of LH release in the anoestrous ewe. Physiology and Behavior 36, 921–924.CrossRefGoogle ScholarPubMed
Cohen-Tannoudji, J, Einhorn, J, Signoret, JP 1994. Ram sexual pheromone: first approach of chemical identification. Physiology and Behavior 56, 955–961.CrossRefGoogle ScholarPubMed
Fabre-Nys, C, Ohkura, S, Kendrick, KM 1997. Male faces and odours evoke differential patterns of neurochemical release in the mediobasal hypothalamus of the ewe during oestrus: an insight into sexual motivation? European Journal of Neuroscience 9, 1666–1677.CrossRefGoogle ScholarPubMed
Franklin, JR, Hutson, GD 1982. Experiments on attracting sheep to move along a laneway. III. Visual stimuli. Applied Animal Ethology 8, 457–482.CrossRefGoogle Scholar
Gelez, H, Fabre-Nys, C 2004. The “male effect” in sheep and goats: a review of the respective roles of the two olfactory systems. Hormones and Behavior 46, 257–271.CrossRefGoogle Scholar
Gonzalez, R, Levy, F, Orgeur, P, Poindron, P, Signoret, JP 1991. Female effect in sheep. II. Role of volatile substances from the sexually receptive female; implication of the sense of smell. Reproduction, Nutrition and Development 31, 103–109.CrossRefGoogle ScholarPubMed
Gray, CA, Bartol, FF, Taylor, KM, Wiley, AA, Ramsey, WS, Ott, TL, Bazer, FW, Spencer, TE 2000. Ovine uterine gland knock-out model: effects of gland ablation on the estrous cycle. Biology of Reproduction 62, 448–456.CrossRefGoogle Scholar
Kendrick, KM 1991. How the sheep’s brain controls the visual recognition of animals and humans. Journal of Animal Science 69, 5008–5016.CrossRefGoogle Scholar
Kendrick, KM, Atkins, K, Hinton, MR, Broad, KD, Fabre-Nys, C, Keverne, EB 1995. Facial and vocal discrimination in sheep. Animal Behavior 49, 1665–1676.CrossRefGoogle Scholar
Kendrick, KM, Atkins, K, Hinton, MR, Heavens, P, Keverne, B 1996. Are faces special for sheep? Evidence from facial and object discrimination learning tests showing effects of inversion and social familiarity. Behavioural Processes 38, 19–35.CrossRefGoogle ScholarPubMed
Knight, TW, Lynch, PR 1980. Source of ram pheromones that stimulate ovulation in the ewe. Animal Reproduction Science 3, 133–136.CrossRefGoogle 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, 125–132.CrossRefGoogle Scholar
Martin, GB, Scaramuzzi, RJ, Oldham, CM, Lindsay, DR 1983. Effects of progesterone on the responses of Merino ewes to the introduction of rams during anoestrus. Australian Journal of Biological Science 36, 369–378.CrossRefGoogle Scholar
Merriam, GR, Wachter, KW 1982. Algorithms for the study of episodic hormone secretion. American Journal of Physiology 243, E310–E318.Google Scholar
Pearce, DT, Oldham, CM 1988. Importance of non-olfactory stimuli in mediating ram induced ovulation in the ewe. Journal of Reproduction and Fertility 84, 333–339.CrossRefGoogle ScholarPubMed
Perkins, A, Fitzgerald, JA 1994. The behavioral component of the ram effect: the influence of ram sexual behavior on the induction of estrus in anovulatory ewes. Journal of Animal Science 72, 51–55.CrossRefGoogle ScholarPubMed
Piggins, D 1992. Visual perception. In Farm animals and the environment (ed. C Philips and D Piggins), pp. 131–158. CAB International, Oxford, UK.Google Scholar
Tate, AJ, Fischer, H, Leigh, AE, Kendrick, KM 2006. Behavioural and neurophysiological evidence for face identity and face emotion processing in animals. Philosophical Transactions of the Royal Society of London B-Biological Science 361, 2155–2172.CrossRefGoogle ScholarPubMed
Walkden-Brown, SW, Martin, GB, Restall, BJ 1999. Role of male–female interaction in regulating reproduction in sheep and goats. Journal of Reproduction Fertility and Development Supplement 54, 243–257.Google ScholarPubMed