Hostname: page-component-77c89778f8-rkxrd Total loading time: 0 Render date: 2024-07-18T14:06:32.005Z Has data issue: false hasContentIssue false

Dynamics of infection in rats given low doses of homogonic and heterogonic Strongyloides ratti

Published online by Cambridge University Press:  06 April 2009

P. A. G. Wilson
Affiliation:
University of Edinburgh, Department of Zoology, West Mains Road, Edinburgh EH9 3JT
Norama E. Simpson
Affiliation:
University of Edinburgh, Department of Zoology, West Mains Road, Edinburgh EH9 3JT

Summary

The results of control infections from 39 experiments using the ‘exact dose’ technique are analysed and compared with earlier large dose experiments with homogonic S. ratti. A smaller error variance and less added variance between experiments accompany the new method, which therefore provides a more precise experimental system. Using the exact dose technique, it is established that the migratory bahaviour of small numbers of L3 of the homogonic strain in lactating animals is the same as that of large numbers. In previous work the rate of migration of the homogonic strain estimated from conventional large dose experiments (Wilson, Cameron & Scott, 1978b) differed from that deduced from the use of radio-isotope labelled L3 (Wilson, 1979). ‘Exact dose’ data support results with the latter technique. There are significant differences between strains. The heterogonic larvae take longer to migrate in lactating hosts and appear to distribute themselves differently between mother and offspring. The consequences of these findings for theories of pathfinding in hosts are discussed. Experiments are also reported which failed to detect any artifact which might have resulted from ether anaesthesia of rats at injection of larval worms. This observation has implications for other studies in progress in this laboratory.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1981

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

Bailenger, J. & Cabannes, A. (1976). Action de la lactation sur le parasitisme des rats par Strongyloides ratti. Annales de Parasitologie Humaine et Comparee 51, 563–76.CrossRefGoogle Scholar
Bailenger, J. & Carcenac, F. (1974). Repercussions du parasitisme par Strongyloides ratti sur le secretion des glucocorticosteroides chez le Rat. International Journal for Parasitology 4, 307–10.CrossRefGoogle Scholar
Connan, R. M. (1970). The effect of host lactation on the self cure of Nippostrongylus brasiliensis in rats. Parasitology 61, 2733.CrossRefGoogle Scholar
Katz, F. F. (1967). On a host sex difference in Strongyloides ratti intestinal worm burdens in rats. Proceedings of the Pennsylvania Academy of Science 41, 30–7.Google Scholar
Schlein, P. A., Zarrow, M. X. & Denenberg, V. H. (1974). Le role de la prolactine dans l'inhibition de la reponse corticosteroidienne surrenale chez le Rat. Journal of Endocrinology 62, 93–9.CrossRefGoogle Scholar
Thoman, E. B., Conner, R. L. & Levine, S. (1970). Adrenal functions during prolonged lactation. Journal of Comparative Physiology and Psychology 70, 364–9.CrossRefGoogle Scholar
Thoman, E. B., Wetzel, A. & Levine, S. (1968). Lactation prevents disruption of temperature regulation and suppresses adrenocortical activity in rats. Communications in Behavioural Biology 2, 165–71.Google Scholar
Tucker, H. A. (1974). General endocrinological control of lactation. In Lactation: A Comprehensive Treatise, vol. 1 (ed. Larson, B. L. and Smith, V. R.), pp. 277326. New York and London: Academic Press.Google Scholar
Wilson, P. A. G. (1977). The effect of the suckling stimulus on the migration of Strongyloides ratti in lactating rats. Parasitology 75, 233–9.CrossRefGoogle ScholarPubMed
Wilson, P. A. G. (1979). Tracking radioactive larvae of Strongyloides ratti in the host. Parasitology 79, 2938.CrossRefGoogle ScholarPubMed
Wilson, P. A. G. (1980 a). Migration of larval roundworms in the rat. Parasitology 81, xi.Google Scholar
Wilson, P. A. G. (1980 b). Recirculation of Strongyloides larvae in the blood of rats and the use of the mammary gland as a sampling device. Proceedings of the Third European Multicolloquium of Parasitology, Abstract 15.Google Scholar
Wilson, P. A. G., Cameron, M. & Scott, D. S. (1978 a). Strongyloides ratti in virgin female rats: studies of oestrous cycle effects and general variability. Parasitology 76, 221–7.CrossRefGoogle ScholarPubMed
Wilson, P. A. G., Cameron, M. & Scott, D. S. (1978 b). Patterns of milk transmission of Strongyloides ratti. Parasitology 77, 8796.CrossRefGoogle ScholarPubMed
Wilson, P. A. G., Gentle, M. & Scott, D. S. (1976 a). Milkborne infection of rats with Strongyloides ratti and Nippostrongylus brasiliensis. Parasitology 72, 355–60.CrossRefGoogle ScholarPubMed
Wilson, P. A. G., Gentle, M. & Scott, D. S. (1976 b). Dynamic determinants of the route of larval Strongyloides ratti in lactating rats and the control of experimental error in quantitative studies of milk transmission of skin penetrating roundworms. Parasitology 73, 399406.CrossRefGoogle ScholarPubMed
Zamirdin, M. & Wilson, P. A. G. (1974). Strongyloides ratti: relative importance of maternal sources of infection. Parasitology 69, 445–53.CrossRefGoogle ScholarPubMed