Parasitological laboratory อ.น.สพ.ดร.กฤษฎา ข าพ ล 17/09/2561

Transcription

1 Parasitological laboratory อ.น.สพ.ดร.กฤษฎา ข าพ ล 17/09/2561

2 Diagnosis Diagnostic techniques: radiography, anatomical pathology, necropsy, microscopic examination of tissue sections, clinical pathology, microbiology, hematology, blood chemistry, immunoserology, parasitology and urinalysis

3 University of Illinois Department of Entomology: Collection and Processing of Samples for Parasitology 1 Internal parasites Blood examination Fecal Examination Necropsy/Biopsy 2. External parasites Skin scraping

4 Reasons for Diagnosis Therapy and prevention depend on accurate ID of a parasite

5 Blood examination -Heartworm infestation of dogs and cats is diagnosed by microscopic examination of the blood for microfilaria (immature larval forms). -PCR -Snap tests -Blood smear, etc.

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9 microbiologia-clinica-28-articulo-thirty-cases-of-human-subcutaneous

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17 Fecal Examination -Ideally, feces should be processed as soon after passage from the animal as possible. -If the processing of a fecal specimen must be delayed, it may be: refrigerated (but not frozen) for several days ( not recommended for samples with live larvae that you intend to examine using the Baermann technique). fixed, e.g., 10% formalin (5% formalin-saline is better for protozoal cysts). Add fixative to feces at a ratio 3:1 (v:v) and mix well. (Not for Baermann technique.)

18 If an animal has been treated with anti-diarrhea preparations containing bismuth or kaolin, mineral oil, oral contrast material (barium) for radiology (all of these materials float) or antibiotics, then parasites may be difficult or impossible to find. Therefore, repeat the fecal exam 5-10 days after treatment withdrawal.

19 Fecal collected Processing -First, examine the feces for blood and other clinical signs, then examine the inside of container for tapeworm segments (which are motile and may move away from the fecal mass). -Many techniques have been devised to increase the likelihood that parasites will be detected in a particular sample of feces. The merits and limitations of representative fecal processing techniques are summarized in the table on the next page. Step-bystep directions for performing the various methods are on the following pages.

20 Repeat Fecal Exams are suggested in the following situations: -Clinical signs suggest parasitism, but initial fecal exam was negative. Repeat in 2 or 3 days. Repeat for a total of 3 times within 7 to 10 days, if no parasites are seen it is likely the animal is not infected. -Following specific therapy of a parasitic infection, have owner submit a fecal specimen 2 weeks following the last administration of drug. (This is late enough that all eggs and cysts will have been cleared from the gut, but, for most parasites, too early for re-infection to be showing up.)

21 Roundworm Ova

22 External Parasites External parasites, especially mites, may be identified by microscopic examination of the fur or by skin scrapings.

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26 Hamster Skin Mite (ventral view) Demodex aurate.

27 Psoregates Mange Mite (ventral view) Isolated from Non-Human Primate

28 Summary Effective treatment can be initiated sooner if diagnostic results can be made quickly available to the clinician treating a disease outbreak. The diagnostic techniques discussed above are equally important in determining the true health status of normal-appearing animals, since subclinical infections can have devastating effects on research results.

29 It is through the combined use of these techniques, coupled with clinical examination and daily observations by laboratory animal technicians, that the health status of both individual animals and entire colonies can be accurately defined.

30 References 1. w.zoetisus.com%2fconditions%2fpages%2fdermatology%2fsuperficial-skin-scraping.aspx&ei=pppoviu6k- 3wBd_cgogK&bvm=bv ,d.dGY&psig=AFQjCNFMZlfcjF2vtaFiWjf9zJsWw2ozCg&ust= ertification%2fcertification%2flat%2flectures%2fchap_10_presentation.ppt&ei=xfdfvpxmci7r8aw8sohocw&usg=afqjcnghejpj ZiQ7Kc2z0LZhpt5AnhTu0A inarynews.dvm360.com%2fdiagnosing-dermatologic-disorders-dogs&ei=fo3ovp3ooabmmaxkohgbg&bvm=bv ,d.dgy&psig=afqjcnfmzlfcjf2vtafiwjf9zjsww2ozcg&ust= inarynews.dvm360.com%2fdiagnosing-dermatologic-disorders-dogs&ei=fo3ovp3ooabmmaxkohgbg&bvm=bv ,d.dgy&psig=afqjcnfmzlfcjf2vtafiwjf9zjsww2ozcg&ust= CgCg&bvm=bv ,d.dGc&psig=AFQjCNGSFbUnD48fQWqt34iyFtw6k9bRdg&ust=