Exercise 5: Sedimentation Technique Flashcards
_______ accomplished by suspending the fecal specimen in
water or aqueous solution of low specific gravity and allowing natural settling to occur, or accelerating the process by centrifugation, leaving the parasites at the bottom of the suspension
Sedimentation technique
________permits the separation of protozoan cysts and certain helminth
eggs from excess debris through the use of a liquid with a high specific gravity. The parasites, by their buoyancy, are recovered in the surface film, and the debris remains in the bottom of the tube
Flotation technique
_________is the most widely used sedimentation
technique. It is approved and recommended by the Department of Health for screening food handlers and Overseas Filipino Workers (OFW).
Formalin–ether sedimentation procedure
_________________ is also based on differences in specific gravity
between the sample debris, which in this case is heavy and sinks to the bottom of the test tube, and potential parasites, which are lighter and float toward the top of the tube. In this procedure, zinc sulfate, with a specific gravity of 1.18 (for fresh stool) to 1.20
(formalin-fixed stool), is used as the concentrating solution. When the zinc sulfate is added to the stool specimen and centrifuged, the parasites float to the surface and can be skimmed from the top of the tube
Zinc Sulfate Technique
It is the alternative for ether and is used the same way and is safer
Ethyl Acetate
It is the extractor of debris and fat from feces and leaves the parasites at the bottom; explosive and flammable
Ether