Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-23T06:16:43.244Z Has data issue: false hasContentIssue false
  • English
  • Français

Seasonal variation in testis diameter and sperm output of rams of breeds of different prolificacy

Published online by Cambridge University Press:  02 September 2010

A. B. M. M. Islam  and
R. B. Land
A. B. M. M. Islam
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
R. B. Land
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
Get access

Summary

Seasonal variation in testis diameter and sperm output was studied in five Finnish Landrace (Finn) and five Tasmanian Merino (Merino) rams, together with five crossbreds between these breeds (Finn-Merino), five selected phenotypically from the Finn-Dorset breed type for high juvenile testis diameter (Finn-Dorset-High) and four for low juvenile diameter (Finn-Dorset-Low). There was marked seasonal variation in testis diameter for each of the breed types. The time of the seasonal increase in testis diameter varied among the breed types, the Merino rams starting earliest—49 days before the Finns. The characteristics of seasonal variation in testis diameter thus showed similarity with the characteristics of seasonal variation in the reproductive performance of females of the breed type. Breed differences in response to season were also demonstrated by a significant breed by season interaction for sperm production, but there were no indications of a useful association between variation in sperm production and variation in the reproductive performance of related females. Overall, differences in adult testis diameter were small relative to those among juveniles.

Type
Research Article
Information
Animal Production , Volume 25 , Issue 3 , December 1977 , pp. 311 - 317
Copyright
Copyright © British Society of Animal Science 1977

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

REFERENCES

Hanrahan, J. P. 1974. Ovulation rate as a selection criterion for fecundity in sheep. Proc.lst WldCongr. Genet, appl. Livestock Prod., 3: 1033–1038. Editorial Garsi, Madrid.Google Scholar
Land, R. B. 1970. The mating behaviour and semen characteristics of Finnish Landrace and Scottish Blackface rams. Anim. Prod. 12: 551–560.Google Scholar
Land, R. B. 1973. The expression of female sex-limited characters in the male. Nature, Lond. 241: 208–209.CrossRefGoogle ScholarPubMed
Land, R. B., Russell, W. S. and Donald, H. P. 1974. The litter size and fertility of Finnish Landrace and Tasmanian Merino sheep and their reciprocal crosses. Anim. Prod. 18: 265–271.Google Scholar
Land, R. B. and Sales, D. I. 1977. Mating behaviour and testis growth of Finnish Landrace, Tasmanian Merino and crossbred rams. Anim. Prod. 24: 83–90.Google Scholar
Lino, B. F. 1972. The output of spermatozoa in rams. II. Relationships to scrotal circumference, testis weight and the number of spermatozoa in different parts of the urogenital tract. Aust. J. biol. Sci. 25: 359–366.CrossRefGoogle ScholarPubMed
Lino, B. F. and Braden, A. W. H. 1972. The output of spermatozoa in rams. I. Relationship with testicular output of spermatozoa and the effect of ejaculations. Aust. J. biol. SW. 25: 351–358.CrossRefGoogle Scholar
Smyth, P. and Gordon, I. 1967. Seasonal and breed variation in the semen characteristics of rams in Ireland. Ir. Vet. J. 21: 222–233.Google Scholar
Thibault, C., Courot, M., Martinet, L., Mauleon, P., Du Mesnil Du Buisson, F., Ortavant, R., Pelletier, J. and Signoret, J. P. 1966. Regulation of breeding season and estrous cycles by light and external stimuli in some mammals. J. Anim. Sci. 25: (Suppl.) 119–142.CrossRefGoogle ScholarPubMed
Wheeler, A. G. and Land, R. B. 1977. Seasonal variation in oestrus and ovarian activity of Finnish Landrace, Tasmanian Merino and Scottish Blackface ewes. Anim. Prod. 24: 363–376.Google Scholar