Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-25T06:28:03.253Z Has data issue: false hasContentIssue false

Ectoparasite impacts on Gerbillus andersoni allenbyi under natural conditions

Published online by Cambridge University Press:  06 April 2009

T. Lehmann
Affiliation:
Department of Animal Sciences, Faculty of Agriculture, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76–100, Israel

Extract

To assess ectoparasite impact on individuals and populations of Gerbillus andersoni allenbyi under natural conditions, I addressed the following questions. Do ectoparasites affect their host fitness and, if so, how? Do ectoparasites affect host population level? Does this parasite–host interaction support the traditional concept of parasite evolution towards avirulence? For this purpose, host infestation, infection, survival, haematological indices, and physical condition were recorded. A field experiment which included manipulating host infestation while recording host survival was conducted to determine the causal relations between these variables. G. a. allenbyi was infested by 2 fleas (Synosternus cleopatrae and Stenoponia tripectinata), 5 mesostigmatid mites (Androlaelaps centrocarpus, A. hirsti, A. insculptus, A. marshalli and Hirstionyssus carticulatus), 1 tick (Rhipicephalus sanguineus), and 1 louse (Polyplax gerbilli). Ectoparasite burden significantly reduced host survival and red blood cell indices (red cell concentration, haemoglobin concentration and haematocrit). Ectoparasite burden did not significantly affect white blood cell concentration. Gerbils were not infected by haemoparasites or gut helminths which potentially could cause anaemia. The causal relationship between S. cleopatrae burden and host survival was established by manipulation of host infestation. Both ectoparasite removal and initial level of infestation significantly affected host survival. Ectoparasites that caused anaemia were not associated with host physical condition (PC), measured as weight/length3. None of the red blood cell indices was correlated with host PC. These results suggest both that host PC was not affected by ectoparasite burden and that exsanguination leading to anaemia was the main effect of the ectoparasites. Ectoparasite pressure on the host population (based on the ectoparasite effects as estimated by statistical models, combined with dispersion of the infestation within the host population) changed seasonally and was greatest when host density was the highest. A large segment of the gerbil population was affected by ectoparasites during the entire year. An explanation for the evolution of parasite virulence, contrasting parasites that evolve towards increased virulence with parasites that evolve towards avirulence is presented. This classification is primarily based on whether parasite impact is equated with a higher efficiency of host exploitation, or whether it is a ‘side effect’ of parasite biology.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1992

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

Abramsky, Z. (1984). Population biology of Gerbillus allenbyi in northern Israel. Mammalia 48, 197206.CrossRefGoogle Scholar
Aldrich, J. H. & Nelson, F. D. (1984). Linear Probability, Logit and Probit Models. Beverly Hills, London and New Delhi: Sage Publications (45).CrossRefGoogle Scholar
Boonstra, R., Krebs, C. J. & Beacham, T. D. (1980). Impact of botfly parasitism on Microtus townsendii populations. Canadian Journal of Zoology 58, 1683–92.CrossRefGoogle Scholar
Buxton, P. A. (1948). Experiments with mice and fleas. I. The baby mouse. Parasitology 39, 119–24.CrossRefGoogle ScholarPubMed
Collins, R. C. & Dewhirst, L. W. (1965). Some effects of the sucking louse, Haematopinus eurysternus, on the cattle on unsupplemented range. Journal of the American Veterinary Medical Association 146, 129–32.Google ScholarPubMed
Costa, M. (1961). Mites associated with rodents in Israel. Bulletin of the British Museum (Natural History) Zoology 8, 170.Google Scholar
Holmes, J. C. (1983). Evolutionary relationships between parasitic helminths and their hosts. In Coevolution (ed. Futuyma, D. J. & Slatkin, M.), pp. 161185. Sunderland, Massachusetts, USA: Sinauer Association.Google Scholar
Jain, N. C. (1986). Schalm's Veterinary Hematology. Philadelphia: Lea and Febiger.Google Scholar
Kettle, P. R. (1974). The influence of cattle lice (Damalinia bovis and Linognathus vituli) on weight gain in beef animals. New Zealand Veterinary Journal 22, 10–1.CrossRefGoogle ScholarPubMed
Kettle, P. R. & Pearce, D. M. (1974). Effect of the sheep body louse (Damalinia ovis) on host weight gain and fleece value. Journal of Experimental Agriculture 2, 219–21.Google Scholar
Kim, C. K. (1985). Evolutionary relationships of parasitic arthropods and mammals. In Coevolution of Parasitic Arthropods and Mammals (ed. Kim, C. K.), pp. 382. New York: John Wiley & Sons.Google Scholar
King, C. M. (1976). The fleas of a population of weasels in Wytham Woods, Oxford. Journal of Zoology 180, 525–35.CrossRefGoogle Scholar
Lehmann, T. (1989). Population biology of the flea Synosternus cleopatrae with emphasis on host–parasite relations. M.Sc. thesis. (In Hebrew, with English summary). The Hebrew University of Jerusalem, Israel.Google Scholar
Lewis, R. (1967). The fleas (Siphonaptera) of Egypt: an illustrated and annotated key. Journal of Parasitology 53, 863–85.CrossRefGoogle ScholarPubMed
Marshall, A. G. (1981). The Ecology of Ectoparasitic Insects. London and New York: Academic Press.Google Scholar
May, R. M. & Anderson, R. M. (1983 a). Epidemiology and genetics in the coevolution of parasites and hosts. Proceedings of the Royal Society of London, B 219, 281313.Google ScholarPubMed
May, R. M. & Anderson, R. M. (1983 b). Parasite–host coevolution. In Coevolution (ed. Futuyma, D. J. & Slatkin, M.). pp. 186206. Sunderland, Massachusetts, USA: Sinauer Association.Google ScholarPubMed
Mead-Briggs, A. R. (1964). Some experiments concerning the interchange of rabbit fleas, Spilopsyllus cunciculi (Dale), between living rabbit hosts. Journal of Animal Ecology 33, 1326.CrossRefGoogle Scholar
Muirhead-Thomson, R. C. (1968). Ecology of Insect Vector Populations. London and New York: Academic Press.Google Scholar
Nelson, W. A., Bell, J. F., Clifford, C. M. & Keirans, J. E. (1977). Interactions of ectoparasites and their hosts. Journal of Medical Entomology 13, 389428.CrossRefGoogle ScholarPubMed
Nelson, W. A., Shemanchuk, J. A. & Haufe, W. O. (1970). Haematopinus eurysternus: blood of cattle infested with the short-nosed cattle louse. Experimental Parasitology 28, 263–71.CrossRefGoogle ScholarPubMed
Rand, A. S., Guerrero, S. & Andrews, R. M. (1983). The ecological effects of malaria on populations of the lizard Anolis limifrons on Barro Colorado Island, Panama. In Advances in Herpetology and Evolutionary Biology (ed. Rhodin, A. G. J. & Miyata, K.), pp.455–71. Special Publication of The Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts.Google Scholar
Rothschild, M. & Ford, R. (1964). Breeding of the rabbit flea (Spilopsyllus cuniculi (Dale)) controlled by the reproductive hormones of the host. Nature, London 201, 103–4.CrossRefGoogle Scholar
Schall, J. J. (1983). Lizard malaria: costs to vertebrate host's reproductive success. Parasitology 87, 16.CrossRefGoogle Scholar
Schall, J. J., Bennett, A. F. & Putnan, R. W. (1982). Lizards infected with malaria: physiological and behavioural consequences. Science 217, 1057–9.CrossRefGoogle Scholar
Schall, J. J. & Sarni, G. A. (1987). Malarial parasitism and the behavioural time budget of the lizard Sceloporus occidentalis. Copeia 1, 8493.CrossRefGoogle Scholar
Scott, M. E. (1988). The impact of infection and disease on animal populations: implications for conservation biology. Conservation Biology 2, 4056.CrossRefGoogle Scholar
Steelman, C. D. (1976). Effects of external and internal arthropod parasites on domestic livestock production. Annual Review of Entomology 21, 155–78.CrossRefGoogle ScholarPubMed
Theodor, O. & Costa, M. (1967). A Survey of the Parasites of Wild Mammals and Birds in Israel. (I) Ectoparasites. Jerusalem: Israel Academy of Sciences and Humanities.Google Scholar
Traub, R. (1985). Coevolution of fleas and Mammals. In Coevolution of Parasitic Arthropods and Mammals, (ed. Kim, C. K.), pp. 295437. New York: John Wiley and Sons.Google Scholar
Waisel, Y., Pollak, G. & Cohen, Y. (1982). The Ecology of Vegetation of Israel. (In Hebrew). Tel Aviv University.Google Scholar
Walton, K. C. & Page, R. J. C. (1970). Some ectoparasites found on polecats in Britain. Nature in Wales 12, 32–4.Google Scholar
Wiger, R. (1977). Some pathological effects of endoparasites on rodents with special reference to the population ecology of microtines. Oikos 29, 598606.CrossRefGoogle Scholar