Hostname: page-component-76fb5796d-5g6vh Total loading time: 0 Render date: 2024-04-28T10:59:07.468Z Has data issue: false hasContentIssue false

The effect of litter size upon foetal growth rate and the placental transfer of calcium and phosphorus in superovulated Scottish half-bred ewes

Published online by Cambridge University Press:  09 March 2007

A. R. Twardock
Affiliation:
Agricultural Research Council, Institute for Research on Animal Diseases, Compton, Newbury, Berkshire
H. W. Symonds
Affiliation:
Agricultural Research Council, Institute for Research on Animal Diseases, Compton, Newbury, Berkshire
B. F. Sansom
Affiliation:
Agricultural Research Council, Institute for Research on Animal Diseases, Compton, Newbury, Berkshire
G. J. Rowlands
Affiliation:
Agricultural Research Council, Institute for Research on Animal Diseases, Compton, Newbury, Berkshire
Rights & Permissions [Opens in a new window]

Abstract

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.

1. The ovulation rate of forty-eight Scottish half-bred ewes was increased by using pregnant mare's serum gonadotrophin thus inducing litters of one to four foetuses.

2. The effects of increased litter size upon the foetal growth rate and upon the rate of transfer of calcium and phosphorus across the placenta were studied at 108–112, 122–126 and 136–140 d gestation.

3. The number of foetuses had little effect upon foetal weight at 112 d, the mean weights of a singleton, twin, triplet or quadruplet being similar. However, by 140 d mean foetal weight decreased markedly as litter size increased.

4. Failure of individual quadruplets to grow as fast as a singleton was associated with a limitation in the capacity of the placenta for transferring minerals. The maximum rates of transfer of Ca and P, whatever the number of foetuses, were approximately 2·8 and 1·4 g/d respectively. These rates were attained by 112 d when quadruplets were being carried, by 126 d for triplets, and by 140 d for twins.

Type
Research Article
Copyright
Copyright © The Nutrition Society 1973

References

REFERENCES

Braithwaite, G. D., Glascock, R. F. & Riazuddin, Sh. (1969). Br. J. Nutr. 23, 827.CrossRefGoogle Scholar
Braithwaite, G. D. & Riazuddin, Sh. (1971). Br. J. Nutr. 26, 215.CrossRefGoogle Scholar
Gibbons, R. A. & Sellwood, R. S. (1968). Int. J. appl. Radiat. Isotopes 19, 129.CrossRefGoogle Scholar
Kessler, G. & Wolfman, M. (1964). Clin. Chem. 10, 686.CrossRefGoogle Scholar
MacDonald, N. S., Hutchinson, D. L., Hepler, M. & Flynn, E. (1965). Proc. Soc. exp. Biol. Med. 119, 476.CrossRefGoogle Scholar
Parker, R. P. & Elrick, R. H. (1966). Int. J. appl. Radiat. Isotopes 17, 361.CrossRefGoogle Scholar
Rowson, L. E. A. (1971). J. Reprod. Fert. 26, 113.CrossRefGoogle Scholar
Rowson, L. E. A., Lawson, R. A. S. & Moore, R. M. (1971). J. Reprod. Fert. 25, 261.CrossRefGoogle Scholar
Simpson (1743). Mathematical Dissertation. (Quoted by H. Lamb in An Elementary Course of Infinitesimal Calculus 1947), p. 260. London: Cambridge University Press.Google Scholar
Symonds, H. W., Manston, R., Payne, J. M. & Sansom, B. F. (1966). Br. vet. J. 122, 196.CrossRefGoogle Scholar
Symonds, H. W., Sansom, B. F. & Twardock, A. R. (1972). Res. vet. Sci. 13, 272.CrossRefGoogle Scholar
Twardock, A. R., Symonds, H. W. & Sansom, B. F. (1971). In Mineral Studies with Lotopes in Domestic Animals, p. 139. Vienna: International Atomic Energy Agency.Google Scholar
Wasscrman, R. H., Comar, C. L., Nold, M. M. & Lengemann, F. W. (1957). Am. J. Physiol. 189, 91.CrossRefGoogle Scholar