Hostname: page-component-848d4c4894-cjp7w Total loading time: 0 Render date: 2024-07-01T04:46:18.911Z Has data issue: false hasContentIssue false

Growth and development of rats artificially reared on rats 'milk or rats' milk/milk-substitute combinations

Published online by Cambridge University Press:  09 March 2007

J. Tonkiss
Affiliation:
Department of Child Health, University of Manchester, The Medical School, Oxford Road, Manchester MI3 9PT
J. L. Smart
Affiliation:
Department of Child Health, University of Manchester, The Medical School, Oxford Road, Manchester MI3 9PT
R. F. Massey
Affiliation:
Department of Child Health, University of Manchester, The Medical School, Oxford Road, Manchester MI3 9PT
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. Rat pups were artificially reared (AR) from post-natal day 5 by intermittent gastric infusion. Mother-reared (MR) siblings served as controls. Fourteen measures of body and organ growth were taken at the end of each experiment.

2. In Expt 1, two batches of pups were given rats' milk only, obtained by manual expression from anaesthetized dams.

3. The first batch, reared to 12 d, grew less well than the MR group, probably because they received too little milk. However, relative to body-weight, organ weights were as great or greater than those of MR pups, except for heart weight. The second batch, given more milk and reared to 20 d, showed no deficits in organ or body-weights, but excesses in kidney, gastrocnemius muscle, stomach and caecum weights. There were no losses from ‘bloat’, a condition of gastrointestinal distention often encountered in artificial rearing with milk substitutes.

4. Obtaining rats' milk is extremely labour-intensive and in Expt 2, more economical regimens were devised in which pups were started off on expressed rats' milk and then changed to a milk substitute resembling rats' milk in composition, either abruptly at 12 d or gradually between 8 and 17 d.

5. Both regimens were successful, in that there were no losses from bloat and most measures of growth were at least as great as in the MR group. Only heart weight was lower in both AR groups and adrenal weight in the abruptly changed AR group. The weights of the stomach and caecum and the length of the small intestine were all high in both AR groups.

6. It is concluded that giving rat pups expressed rats' milk for the first few days of artificial rearing largely avoids the problem of bloat and results in satisfactory growth.

Type
Papers of direct relevance to Clinical and Human Nutrition
Copyright
Copyright © The Nutrition Society 1987

References

REFERENCES

Anderson, R. R. & Turner, C. W. (1963). Proceedings of the Society for Experimental Biology and Medicine 113, 334336.CrossRefGoogle Scholar
Diaz, J., Moore, E., Petracca, F., Schacher, J. & Stamper, C. (1981). Physiology and Behavior 27, 11031105.CrossRefGoogle Scholar
Diaz, J., Moore, E., Petracca, F., Schacher, J. & Stamper, C. (1982). Journal of Nutrition 112, 841847.CrossRefGoogle Scholar
Diaz, J., Samson, H., Kessler, D., Stamper, C., Moore, E., Robisch, E. & Hodson, A. (1980). Pediatric Research 14, 595.Google Scholar
Dymsza, H. A., Czajka, D. M. & Miller, S. A. (1964). Journal of Nutrition 84, 100106.CrossRefGoogle Scholar
Hall, W. G. (1975). Science 190, 13131315.CrossRefGoogle Scholar
Messer, M., Thoman, E. B., Terrasa, A. G. & Dallman, P. R. (1969). Journal of Nutrition 98, 404410.CrossRefGoogle Scholar
Naismith, D. J., Mittwoch, A. & Platt, B. S. (1969). British Journal of Nutrition 23, 683693.CrossRefGoogle Scholar
Shirley, B. (1984). Laboratory Animal Science 34, 169172.Google Scholar
Smart, J. L., Stephens, D. N. & Katz, H. B. (1983). British Journal of Nutrition 49, 497506.CrossRefGoogle Scholar
Smart, J. L., Stephens, D. N., Tonkiss, J., Auestad, N. S. & Edmond, J. (1984). British Journal of Nutrition 52, 227237.CrossRefGoogle Scholar
Sonnenberg, N., Bergstrom, J. D., Ha, Y. H. & Edmond, J. (1982). Journal of Nutrition 112, 15061514.CrossRefGoogle Scholar
Souders, H. J. & Morgan, A. F. (1957). American Journal of Physiology 191 (1), 17.CrossRefGoogle Scholar
Tonkiss, J., Smart, J. L., Auestad, N. S. & Edmond, J. (1985). Journal of Pediatric Gastroenterology and Nutrition 4, 818825.Google Scholar