Skip to main content Accessibility help

Influence of mating pressure and season on the semen characteristics of rams

  • T. Tomkins (a1) and M. J. Bryant (a1)


Two groups of 4 Suffolk rams were each subjected to mating pressures of 90 ejaculates (High) and 45 ejaculates (Low) over a 3-day period during summer and autumn. Every sixth (High) or every third (Low) ejaculate was collected into an artificial vagina and assessed for volume, sperm density, total sperm per ejaculate, motility and percentage of live and abnormal sperm.

There was a general lowering of semen quantity and quality with successive ejaculations. Rate of change of the various measures was greater on the High than on the Low mating pressure. Volume and percentage of live sperm showed a greater decline, and percentage of abnormal sperm a greater increase, during the autumn than during the summer. Density showed a greater decline in summer than in autumn.

The significance of the changes in semen characteristics observed is considered in relation to requirements for high fertility after pro-gestagen treatment.



Hide All
Allison, A. J. 1972. The effect of mating pressure on characteristics of the ejaculate in rams and on reproductive performance in ewes. Proc. N.Z. Soc. Anim. Prod. 32: 112113.
Allison, A. J. and Robinson, T. J. 1971. Fertility of progestagen-treated ewes in relation t o the numbers and concentration of spermatozoa in the inseminate. Aust. J. biol. Sci. 24: 10011008.
Amir, D. 1966. The effect of successive ejaculations at different seasons on some semen characteristics of Awassi rams. Ktavim 16: 4144.
Bryant, M. J. and Tomkins, T. 1975. The flock-mating of progestagen-synchronized ewes. 1. The influence of ram-to-ewe ratio upon mating behaviour and lambing performance. Anim. Prod. 20: 381390.
Chang, M. C. 1945. The sperm production of adult rams in relation to frequency of semen collection. J. agric. Sci., Camb. 35: 243246.
Comstock, R. E., Green, W. W., Winters, L. M. and Nordskoo, A. W. 1943. Studies of semen and semen production. Tech. Bull. Minn, agric. Exp. Stn, No. 162.
Hulet, C. V. and Ercanbrack, S. K. 1962. A fertility index for rams. J. Anim. Sci. 21: 489493.
Mattner, P. E. and Braden, A. H. W. 1967. Studies in flock mating of sheep. 2. Fertilization and prenatal mortality. Aust. J. exp. Agric. Anim. Husb. 7: 110116.
Nelson, E. A. 1958. Factors influencing semen quality and reproductive efficiency in rams. Diss. Abstr. 18: 1192 (Abstr.).
Pepelko, W. E. and Clegg, M. T. 1965. Studies of mating behaviour and some factors influencing the sexual response in the male sheep Ovis aries. Anim. Behav. 13: 249258.
Quinlivan, T. D. 1970. The relationship between numbers of spermatozoa inseminated and fertilization rate of ova in ewes treated with fluoro-progestagen intra-vaginal sponges in summer and autumn. J. Reprod. Fert. 23: 87102.
Robinson, T. J. 1967. Control of the ovarian cycle in the sheep. In Reproduction in the Female Mammal (ed. Lamming, G. E. and Amoroso, E. C.). Proc. 13th Easter School in Agricultural Science, Univ. Nottingham, 1966, pp. 373418. Butterworth, London.
Salamon, S. 1962. Studies on the artificial insemination of Merino sheep. III. The effect of frequent ejaculation on semen characteristics and fertilizing capacity. Aust. J. agric. Res. 13: 11371150.
Salamon, S. 1964. The effect of frequent ejaculation in the ram on some semen characteristics. Aust. J. agric. Res. 15: 950960.
Salamon, S. and Lindsay, D. R. 1962. The training of rams for the artificial vagina, with some observations on ram behaviour. In Artificial Breeding of Sheep in Australia. Proc. Conf. Univ. New South Wales, 1961 (ed. Roberts, E. M.) pp. 173182, University of New South Wales.
Schindler, H., Volcani, R. and Eyal, E. 1957. Some characteristics of the semen of Awassi rams. Ktavim 5: 4551.
Smyth, P. and GORDON, 1.1967. Seasonal and breed variations in the semen characteristics of rams in Ireland. Ir. vet. J. 21: 222233.
Wiggins, E. L., Terrill, C. E. and Emik, L. O. 1953. Relationships between libido, semen characteristics and fertility in range rams. J. Anim. Sci. 12: 684696.

Influence of mating pressure and season on the semen characteristics of rams

  • T. Tomkins (a1) and M. J. Bryant (a1)


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed