Submission Process

Simply follow these steps to send Histovet a sample for analysis.


Download and fill out the submission form or submit through the online form. We have also included some extra forms for more detailed information if needed.

Note: The more information you are able to give, the better.  Outlining exactly what you are looking for helps ensure our report will meet your expectations.

Please contact us for shipping instructions appropriate to your location. Use the following;

Local: 519-822-4486
Toll free: 1-800-853-PATH (7284)
Alternatively e-mail us at

Shipping Large Samples


If you have a large sample that will not fit in one of our standard formalin bottles:

a) Fix the sample in a large volume of 10% formalin (at least 5 times the volume of the sample) for 24 – 48 hours, depending upon the size of the sample. Remove the fixed sample from the formalin and place it, dripping wet, in a ziploc bag. DO NOT ADD ANY FORMALIN TO THAT BAG! Place that bag in two additional sealed ziploc bags to prevent leakage or desiccation during shipping.

b) Take 4-5 representative* samples, each about the size of a nickel, from the periphery of the large mass, put them in one of our regular formalin bottles and ship as usual.

* "Representative" may be different for different samples. Most commonly, it would mean samples to include the margin between normal and abnormal tissue around the periphery of suspected neoplasms. If you need additional guidance, please call and we will be happy to assist.
Guidelines For Marking Tumor Margins


Determine which margin or margins are of greatest concern in terms of incomplete excision. This is usually the deepest border rather than the horizontal margins.
  • Gently blot dry the surface to which the ink* will be applied.
  • Apply the ink with a small brush or cotton applicator (a nail polish brush is perfect).
  • Let it dry for just a minute or two, and then drop the tissue into the formalin.
  • The ink binds to the tissue and stays with the tissue throughout processing, allowing me to judge with 100% certainty what is truly a surgical margin.
  • To view our instructional video on inking surgical margins, please see:

If you wish to be really sophisticated, apply the ink very specifically and focally to those areas of greatest concern. I will then specifically examine those regions microscopically, so you are truly "in control" of exactly where I direct my attention. You can even get inks of different colors so you can provide a true color key for different portions of the large mass.

*The ink must be genuine India ink which is a suspension of particles that bind to the tissue. Such inks are available through various surgical supply companies, but suitable alternatives include tattoo ink, drawing ink from an art store, or stamp pad refill ink. You should practice your technique and confirm the suitability of each particular ink on some non-critical case before you have to use it "for real". Just alert me to the fact that you have applied ink and that you wish me to comment on the results.
Winterized Formalin Instructions


Worried about sample freezing this winter?
If your samples freeze during shipment, the histology is almost impossible to interpret. To prevent freezing, you should add methanol, ethanol or isopropyl alcohol to the 10% formalin that you would usually use for fixation. How much to add depends on how cold it is in your area and here in Southern Ontario on the day of shipment (most freezing occurs while the sample is being transported by ground en route to and from the courier depots).
  • If the expected temperature is -10°C, you should add 10 ml of alcohol to every 50 ml of formalin
  • If the expected temperature is -20°C, you should add 15 ml of alcohol to every 50 ml of formalin
  • If the expected temperature is -30°C, you should add 20 ml of alcohol to every 50 ml of formalin (. . . and then consider moving elsewhere!!!)