Hostname: page-component-8448b6f56d-c4f8m Total loading time: 0 Render date: 2024-04-17T23:46:25.793Z Has data issue: false hasContentIssue false

Genetic aspects of fertility and endocrine organ size in rats*

Published online by Cambridge University Press:  14 April 2009

R. J. Mullen
Affiliation:
Genetics Program, Zoology Department, University of New Hampshire, Durham, N.H., U.S.A.
F. K. Hoornbeek
Affiliation:
Genetics Program, Zoology Department, University of New Hampshire, Durham, N.H., U.S.A.
Rights & Permissions [Opens in a new window]

Summary

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

An investigation of the genetic aspects of fertility was conducted among inbred and hybrid generations of rats. The high-fertility LEW strain and the low fertility CAS strain were crossed and their hybrids inbred for four generations. Litter size, ovulation rate, sterility, and the weights of the thyroid, pituitary, adrenals, testes, seminal vesicles, ventral prostate, uterus, and ovaries were analysed in inbred and hybrid rats for evidence of strain differences and heterosis and in successive generations of sib matings for inbreeding depression.

CAS females produced smaller litters and had smaller thyroids, pituitaries, adrenals, ovaries, and uteri than LEW females. CAS males had larger testes but smaller adrenals than LEW males. Results of crosses included heterosis for female pituitary and ovary weights, but inbreeding depression for the weights of male adrenals, seminal vesicles, and ventral prostates, and female thyroids and uteri. Ovulation rate did not differ between strains and was not an important determinant of litter size in this study.

The decrease in litter size as a result of inbreeding was due partly to the inbreeding of the parents and partly to the inbreeding of the litter.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1970

References

REFERENCES

Bowman, J. C. & Falconer, D. S. (1960). Inbreeding depression and heterosis of litter size in mice. Genetical Research 1, 262274.CrossRefGoogle Scholar
Cole, H. H. & Casady, R. B. (1947). Studies on indices and causes of prolificacy in rats. Endocrinology 41, 119126.CrossRefGoogle ScholarPubMed
Craig, J. V., Casida, L. E. & Chapman, A. B. (1954). Male infertility associated with lack of libido in the rat. American Naturalist 88, 365372.CrossRefGoogle Scholar
Falconer, D. S. (1960). Introduction to Quantitative Genetics. New York: Ronald Press.Google Scholar
Falconer, D. S. & Roberts, R. C. (1960). Effect of inbreeding on ovulation rate and foetal mortality in mice. Genetical Research 1, 422430.CrossRefGoogle Scholar
Hoornbeek, F. K. (1968). Mating success and litter size variation within and between inbred and hybrid generations of rats. Journal of Animal Science 27, 13781382.CrossRefGoogle Scholar
Jinks, J. L. & Broadhurst, P. L. (1963). Diallel analysis of litter size and body weight in rats. Heredity 18, 319336.CrossRefGoogle Scholar
McCarthy, J. C. (1967). The effects of inbreeding on the components of litter size in mice. Genetical Research 10, 7380.CrossRefGoogle ScholarPubMed
Roberts, R. C. (1960). The effects on litter size of crossing lines of mice inbred without selection. Genetical Research 1, 239252.CrossRefGoogle Scholar
Robinson, Roy (1956). Genetics of the Norway rat. Oxford: Pergamon Press.Google Scholar
Sreebny, L. M., Meyer, J., Bachem, E. & Weinmann, J. P. (1957). Restoration of enzymatic activity in the submaxillary gland of the hypophysectomized albino rat. Endocrinology 60, 200204.CrossRefGoogle Scholar
Sreebny, L. M., Rosen, S., Bachem, E., Hunt, H. R. & Hoppert, C. A. (1959). The effect of castration on the submaxillary gland of Hunt-Hoppert caries-resistant and caries-susceptible rats. Journal of Dental Research 38, 6771.CrossRefGoogle ScholarPubMed
Steel, R. G. D. & Torrie, J. H. (1960). Principles of Procedures and Statistics. New York: McGraw-Hill.Google Scholar