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in Table 3.11. Molecular methods of insect iden- 5 Fixatives are reagents that solidify cells and prevent
tification are also gaining popularity. them from undergoing autolytic degeneration.
There are a lot of important animal diseases 6 Diff Quick™ is a commercial stain manufactured by
B.M. Brown Ltd, Reading, UK.
linked to arthropods but these are beyond the 7 Depends on the type of tick and the duration of the
scope of this book. The tables and illustrations life cycle which may in turn depend on the climate.
in this chapter are provided to give an overview
of some of the main features of arthropod life
cycles and morphology but additional infor- Bibliography
mation may be found in the texts listed in the
reference section (see also Chapter 14). For Bowman, D.D., Georgi, J.R. (2009) Georgi’s
further information on this subject it would be Parasitology for Veterinarians, 9th edn. Saunders,
useful to visit an institute which offers specialist Elsevier Health Sciences, Philadelphia, PA.
training and expertise in entomology and vector Goddard, J. (2008) Infectious Diseases and Arthropods,
2nd ed. Humana Press, Springer Nature, Cham,
borne diseases. Switzerland.
Kasai, T. (1999) Veterinary Parasitology. Butterworth
Heinemann, Oxford.
Endnotes Merck (2000) The Merck Veterinary Manual, http://
www.merckvetmanual.com/mvm/index.jsp. accessed
June 2011.
1 If a centrifuge is not available prepare a standard
suspension as outlined above (without step 7). Mullen, G., Durden, L. (2009) Medical and Veterinary
Allow the sample to settle by gravity for 15–20 min Entomology. Elsevier, Academic Press,. Cambridge,
and discard the supernatant. Note: this step may MA.
affect the sensitivity of detection. Soulsby, E.J.L. (1982) Helminths, Arthropods and
2 Use a shorter time for fragile thin walled parasite Protozoa of Domesticated Animals. Bailliere
eggs such as fluke eggs. The latter will collapse but Tindall, London.
should still be recognizable. Collapsed eggs may Taylor, M.A., Coop, R.L., Wall, R.L. (2007) Veterinary
sink so examination should be done within a rea- Parasitology, 3rd edn. Blackwell Publishing,
sonable time after flotation. Oxford.
3 Plasma pepsinogen levels are elevated in any dis- Urqhuart, G.M., Armour, J., Duncan, J.L., Dunn, A.M.,
ease which causes abomasal crypt damage and this Jennings, F.W. (1996) Veterinary Parasitology, 2nd
is an indirect indication of the presence of Ostertagia edn. Longman Scientific and Technical, Harlow.
sp. in cattle. In severe cases there is usually evi- Zajac, A., Conboy, G.A. (2006) Veterinary Clinical
dence of severe abomasal ulceration at necropsy. Parasitology. Blackwell Publishing, Ames, IA.
4 https://www.cdc.gov/parasites/trichinellosis/biology.
html.

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