Submission Guidelines: 

• Fecal samples must be fresh, preferably less than 48 hours old.
• Refrigerate samples as soon as possible after collection, but DO NOT FREEZE.
• To prevent sample processing delays, please ensure the submission form and transport containers are labeled consistently and legibly.
• Refer to the chart below for more specific specimen collection recommendations.

Test Type




Parasite identification

arthropods, cestodes, nematodes, trematodes

Whole parasite (in 70% ethanol, 5-10% formalin, or refrigerated water); arthropod (in 70% ethanol,  5-10% formalin; or live - not adhered to tape)


Fecal flotation - quantitative

cestode eggs, nematode eggs, coccidian oocysts, Cryptosporidium spp. oocysts, some protozoan cysts

Feces = 5gm fresh or refrigerated

Egg/oocyst counts do not correlate directly with parasite burden. May be useful for managing deworming and anti-protozoal protocols.

Fecal flotation – qualitative (Sheather's sugar solution)

cestode eggs, nematode eggs, coccidian oocysts, Cryptosporidium spp. oocysts, some protozoan cysts

Feces = 1gm fresh or refrigerated

Routine fecal exam. Unlikely to detect trematode eggs, protozoan trophozoites, nematode larvae and some protozoan cysts.

Fecal flotation - qualitative (zinc sulfate)

Filaroides hirthi, Giardia spp. cysts, Oslerus osleri, lungworms, protozoa

Feces = 1gm fresh or refrigerated

Preserves protozoal cysts and nematode larvae for identification better than routine qualitative fecal float.

Fecal exam - direct

Cryptosporidium spp., Giardia spp., cestodes, nematode larvae, protozoan trophozoites, trematode eggs

Feces = 1gm fresh or refrigerated

Negative findings are inconclusive, as this method is less sensitive than sedimentation, flotation, or Baermann technique. Preserves delicate forms such as nematode larvae and protozoan trophozoites.

Fecal exam - sedimentation

Parelaphostrongylus sp., Physaloptera spp., cestodes, trematode eggs, amoebae, ciliates, acanthocephalan eggs

Feces = 1gm fresh or refrigerated

More sensitive than direct smear, but less sensitive than flotations or Baermann technique. Detects heavy parasite eggs and Strongyloides stercoralis larvae.

Fecal Cryptosporidium - acid fast stain

Cryptosporidium spp.

Feces = 1gm fresh or refrigerated

Heavy infection can be detected in routine qualitative fecal flotation.

Fecal larval exam - Baermann technique

Larvae of Strongyloides stercoralis, Aelurostrongylus abstrusus, Dictyocaulus spp., Muellerius capillaris, Parelaphostrongylus tenuis, lungworms, nematodes

Feces = 10gm fresh or refrigerated

Takes advantage of the inability of most nematode larvae to swim against gravity. The qualitative fecal flotation with zinc sulfate is the preferred method for Filaroides spp.

Giardia Panel

Giardia spp. (cysts and antigen)

Feces = 2gms fresh or refrigerated

Panel consists of the qualitative zinc sulfate flotation and the Giardia antigen ELISA. Canine and feline samples only.

Canine heartworm antigen test - ELISA

Dirofilaria immitis

Serum, plasma (=1mL); blood in LT or RT tube* (=3mL)

Detects adult female heartworm antigen.

Feline heartworm antibody test - ELISA

Dirofilaria immitis

Serum, plasma (=1mL); blood in LT or RT tube* (=3mL)

Detects feline anti-heartworm antibody.

Knott's test

microfilariae of Dirofilaria immitis and Dipetalonema reconditum

1mL blood in LT tube*

Visualization of microfilariae in blood.

*Tube abbreviations: RT= red top; LT=lavender top

Criteria for sample rejection:
• Mismatch of information on the specimen label and the submission form.
• Inappropriate transport temperature (i.e. Frozen).
• Insufficient quantity (i.e. <10 grams for Baermann technique).

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