Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-25T23:59:38.224Z Has data issue: false hasContentIssue false

Competitive ability of rams selected for high and low levels of sexual performance

Published online by Cambridge University Press:  02 September 2010

H. W. Erhard
Affiliation:
Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB15 8QH
E. O. Price
Affiliation:
Department of Animal Science, University of California, Davis, CA 95616–8521, USA
M. R. Dally
Affiliation:
Hopland Research and Extension Center, 4070 University Road, Hopland, CA 95449, USA
Get access

Abstract

The objective of this study was to determine any differences in the competitive ability of rams differing in levels of sexual performance. Twenty sexually experienced Targhee-type rams were preselected from a population of 95 males for exhibiting relatively high and low ejaculation rates when individually exposed to oestrous ewes for 30 min. Each of 10 high performers (HP) were paired with each of 10 low performers (LP) on three occasions when competing for food (after food deprivation) and twice when competing for an oestrous female. Tests were 5 min in duration. Food-deprived HP and LP rams were equally aggressive when competing for a source offood that could only be accessed by one ram at a time. Time offeeding by HP and LP rams did not differ. HP rams spent more time with the oestrous ewe and attained more mounts in a greater number of pairings than LP rams even though HP and LP rams did not differ in number of successful agonistic interactions (active displacements and successful defences) when competing for the ewe. It was concluded that HP and LP rams, taken as groups, do not differ in their basic competitive ability and that the greater mating success of HP rams can be explained by their higher levels of libido.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1998

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

Fowler, D. G. and Jenkins, L. D. 1976. The effects of dominance and infertility of rams on reproductive performance Applied Animal Ethology 2:327337.CrossRefGoogle Scholar
Lindsay, D. R., Dunsmore, D. G., Williams, J. D. and Syme, G. J. 1976. Audience effects on mating behaviour of rams Animal Behaviour 24: 818821.CrossRefGoogle Scholar
Pepelko, W. E. and Clegg, M. T. 1965. Studies of mating behaviour and some factors influencing the sexual response i n the male sheep, Ovis aries Animal Behaviour 13: 249258.CrossRefGoogle Scholar
Price, E. O., Blackshaw, J. K., Blackshaw, A., Borgwardt, R., Dally, M. R. and BonDurant, R. H. 1994 Sexual responses of rams to ovariectomized and intact estrous ewes. Applied Animal Behaviour Science 42: 6771.CrossRefGoogle Scholar
Price, E. O., Borgwardt, R., Dally, M. R. and Hemsworth, P. H. 1996. Repeated matings with individual ewes by rams differing in sexual performance, journal ofAnimal Science 74: 542544.Google ScholarPubMed
Price, E. O., Erhard, H., Borgwardt, R. and Dally, M. R. 1992. Measures of libido and their relation to serving capacity in the ram Journal ofAnimal Science 70: 33763380.Google ScholarPubMed
Shreffler, C. and Hohenboken, W. D. 1974. Dominance and mating behavior in ram lambs Journal ofAnimal Science 39: 725731.Google ScholarPubMed
Siegel, S. and Castellan, N. J. 1988. Nonparametric statistics for the behavioral sciences, second edition. McGraw-Hill, New York.Google Scholar
Tilbrook, A. J., Cameron, A. W. N. and Lindsay, D. R. 1987. The influence of ram mating preferences and social interaction between rams on the proportion of ewes mated at field joining Applied Animal Behaviour Science 18:173184.CrossRefGoogle Scholar
Zenchak, J. J. and Anderson, G. C. 1980. Sexual performance levels of rams (Ovis aries) as affected by social experiences during rearing Journal of Animal Science 50: 167174.CrossRefGoogle Scholar