Host-finding and host recognition of infective Ancylostoma caninum larvae

doi:10.1016/0020-7519(91)90100-L

International Journal for Parasitology

Volume 21, Issue 4, July 1991, Pages 429-440

https://doi.org/10.1016/0020-7519(91)90100-L Get rights and content

Abstract

A. caninum larvae responded to environmental and host stimuli with four behavioral phases of host-finding. (1) Snake-like movement was stimulated by warmth and by defined vibrations of the substratum. (2) Waving behavior was a prerequisite for the passive change-over to dog hairs. It was stimulated by heat radiation and by the CO₂ content, warmth, and humidity of an air stream. (3) Creeping direction: the larvae were attracted by heat in temperature gradients as weak as 0.04°C mm⁻¹ and by dog hydrophilic skin surface extracts, but not by skin lipids or serum. (4) Penetration into agar was stimulated by heat, dog hydrophilic skin fraction, and dog serum. The effective component of serum had a molecular weight of between 5000 and 30,000 and proved to be a protein, since it lost its effectiveness after digestion with proteinases. Dog saliva, urine, milk, and various pure dog serum components did not stimulate penetration. A. caninum larvae were able to penetrate mouse skin repeatedly, but they did not follow the tracks of previously penetrated larvae in agar.

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Host-finding and host recognition of infective Ancylostoma caninum larvae

Abstract

Experimental Parasitology

Journal of Biological Chemistry

Experimental Parasitology

International Journal for Parasitology

International Journal for Parasitology

Journal of Investigative Dermatology

Comparative Biochemistry and Physiology

Studies on the activity of the infective larvae of the rat strongylid, Nippostrongylus muris

Journal of Parasitology

Comparative studies on the effects of temperature on free-living stages of Placoconus lotoris, Dochmoides stenocephala, and Ancylostoma caninum

Canadian Journal of Zoology

Circular Statistics in Biology

The effect of microenvironment on the freeliving stages of Bunostomum trigonocephalum

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The ecology of immature phases of trichostrongyle nematodes. I. The vertical distribution of infective larvae of Trichostrongylus retortaeformis in relation to their habitat

Parasitology

The ecology of immature phases of trichostrongyle nematodes. II. The effect of climatic factors on the availability of the infective larvae of Trichostrongylus retortaeformis to the host

Parasitology

Behaviour of larval nematodes

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Journal of Parasitology

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A comparative study of tropisms exhibited by different stages of Nippostrongylus muris (Nematoda: Trichostrongylidae)

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The direct development of hookworm after oral infection

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Journal of Helminthology