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The effects of freezing on the viability of Toxocara canis and T. catiembryonated eggs

Published online by Cambridge University Press:  05 June 2009

P. O'Lorcain
P. O'Lorcain
Affiliation:
Zoology Department, Trinity College Dublin, Dublin 2, Ireland
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Abstract

Suspensions of embryonated (L2) Toxocara canis and T. cati eggs were maintained under freezing conditions in order to study the impact on their long term viability The eggs had been removed from the uteri of adult Toxocara spp. worms and the suspended in a 0.4% formalin solution before being frozen in 20 ml plastic tubes in the freezer compartment of a domestic refrigerator. Assessment of embryonated egg viability over a period of 34 days was conducted by microscopic examination under a high light intensity Embryonated T. cati eggs were found to exhibit a greater resistance to freezing than those of T. canis. A difference in the size, design of the egg shell or the metabolism of the larval form may have accounted for the observed differences in the percentage viabilities over time between the two species of Toxocara.

Type
Research Note
Information
Journal of Helminthology , Volume 69 , Issue 2 , June 1995 , pp. 169 - 171
Copyright
Copyright © Cambridge University Press 1995

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