Diagnostic Insights for Veterinary Nurses
April 2020

Test Sample Size Guidelines

By Rachel Corn, VT

To ensure the best possible results from testing, a correct sample size is necessary. Some tests can be completed on a very small amount of sample, while others require a larger section.

Below is a table with some of the common tests and the appropriate sample size. If you are requesting that more than one test be completed on a single sample, a larger sample will be required. In all cases, it never hurts to send an extra sample, in case additional testing is needed.

Fecal Float 0.2 oz of feces 1 Hershey Kiss
Culture For fresh tissue:
A good rule of thumb is to send a piece 3 in. x 3 in.
1 tennis ball
PCR 0.2 oz of tissue or feces or 2.0 ml of fluid/whole blood 1 large marshmallow
Serology 0.5 ml of serum for most tests -
Virology 0.5 ml of serum for most tests -
Necropsy histopathology Tissue no more than 0.5 in. thick -
Histopathology on a mass or spleen The entire mass or spleen -

For more information, please visit Tests and Fees or call Client Care at 866-512-5650.

Next: New Requirements for EIA Testing
Return to Index