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The Distribution of Nematode Eggs when using a Dilution-Egg-Count Procedure*

Published online by Cambridge University Press:  05 June 2009

J. E. Dunn ,
R. W. Poteet  and
D. P. Conway
J. E. Dunn
Affiliation:
Departments of Mathematics and Animal Sciences, University of Arkansas, Fayetteville
R. W. Poteet
Affiliation:
Departments of Mathematics and Animal Sciences, University of Arkansas, Fayetteville
D. P. Conway
Affiliation:
Departments of Mathematics and Animal Sciences, University of Arkansas, Fayetteville
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Extract

By combining a number of well-known but scattered results, a theoretical model has been constructed to explain the observed quadratic increase in sample variance of egg counts over sample mean with increasing egg concentration. Our contention is that the over-dispersion arises because of inherent variation in volumetric deliveries of faecal suspension onto the counting slide. Even though the observed variation of volumetric deliveries appears to be small, we have shown that it is adequate to cause a considerable increase in egg count variance over mean at not unreasonably high concentrations.

Type
Research Article
Information
Journal of Helminthology , Volume 40 , Issue 3-4 , September 1966 , pp. 309 - 322
Copyright
Copyright © Cambridge University Press 1966

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References

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