Laboratory Information and Services


Clinical Services | BILLING | Supplies | COurier


True North Veterinary Diagnostics Inc. is a full service laboratory providing a wide variety of testing including:

Hematology, Chemistry, Urinalysis, Microbiology (culture & susceptibility), Parasitology, Endocrinology, Serology, Cytology, Histology, Immunohistochemistry, and Coggins testing (EIA). If you are not finding the test you are looking for in the test directory search, please call the laboratory- we are able to accommodate most requests.

At TNVD we strive to provide consistent, cost-effective results to help veterinarians better treat their patients.

We will not ask our clients to sign any contracts.
Reports come with pathologist interpretations, at no additional charge.
Same fees for all clients, regardless of number of submissions.
We have extended laboratory hours, and are open most holidays to serve you.
A portion of TNVD’s profits go back to serving veterinarians, and promoting animal welfare.


All accounts are billed during the first week of each month with 30 day terms. Payment to the account is expected within 30 days of the statement date and financial charges will be applied to balances carried forward beyond 60 days. Billing is done by statement only-no invoices will be issued.

Payment options include cheque and credit card (VISA, Amex and Mastercard). Please contact our accounts receivable department to initiate automatic credit card payment or to discuss any questions or concerns you may have regarding your account. Charges to your credit card will occur within the first week of each month unless otherwise requested by the client.


We are pleased to offer several types of collection tubes and containers to our submitting clients free of charge, or for a nominal fee for select supplies. These supplies can be ordered online via TNVD's Lablink, or a supply order form can be faxed to the clinic upon request. Please allow 4-5 days for delivery after receipt of the order form.

Red top tube (RTT):  5 or 10ml glass vials or microtainer. This is a plain sterile, additive-free tube. Vacuum and microtainer tubes are available. It can be used for collecting serum as well as a general collection container for urine, tissue, and for collection of fluid for culture. When a test is designated for a RTT, do not substitute an SST tube as the gel barrier may interfere with analysis (e.g., the gel will absorb phenobarbital; the gel can cause falsely decreased values in progesterone). Samples from fluid cytology should be submitted in both RTT and LTT tubes, for culture and cytology respectively. 

Serum separator tube (SST): 3.5ml, 5ml, microtainer. This tube contains a clot activator and separator gel. Vacuum and microtainer tubes are available. Invert the tube to activate clotting and allow to stand in an upright position for 20-30 minutes before centrifuging. Centrifuge for 10-15 minutes to ensure good separation. If submitting frozen transfer the serum to a plastic tube (do not freeze fluids in glass tubes). Do not use these tubes for phenobarbital, progesterone, urinalysis, or as indicated in sample requirements.

Lavender top tube (LTT): 2ml, 6ml, microtainer. This tube contains EDTA as an anticoagulant and is used for most hematologic analysis. The tubes should be filled with an appropriate volume of blood for the tube. For microtainer tubes indicators are on the side, for vacuum tubes the blood should be at least to the bottom of the sticker. An inappropriately low volume of blood to anticoagulant can interfere with RBC indices. Please note that EDTA contamination of a sample for chemistry will falsely decrease calcium and increase potassium. EDTA can be bacteriostatic, therefore please do not submit samples for culture in lavender top tubes.

Blue top tube (BTT): 1.5ml microtainer, 2.7ml. These tubes contain sodium citrate as an anticoagulant and are use for coagulation testing. There is no other tube that can used for PT/PTT, vWF. It is very important to obtain the sample atraumatically and maintain the correct ratio of blood to anticoagulant (1 part sodium citrate to 9 parts of blood). Invert the tube 6-10 times immediately after collection. Please see the protocol section for more information. Plasma can be stored frozen for PT/PTT.

GTT (Green top tube): 4ml tube or microtainer. This tube contains lithium heparin as an anticoagulant. Heparinized plasma can be substituted for serum for most chemistry tests. This is also the preferred anticoagulant for some avian species such as ostrich. 

Grey top tube: 2ml tube. Primarily for glucose determination. This tube contains sodium fluoride which prevents cells from utilizing glucose during transport to the lab and therefore prevents falsely low glucose. Ideally samples should be spun, plasma collected and placed into another grey top tube, especially if there is a delay of >24 hours in sample getting to the lab. A grey top sample can be submitted with panels at no additional charge.

Dark blue top tube (DBTT): 6ml. This tube is for trace mineral analysis.

ACT tube: (Available for charge). These tubes contain diatomaceous earth as a clot activator are used as a crude patient-side indicator of hemostasis. Severely decreased or inhibited coagulation factors and severe thrombocytopenia will cause prolonged clotting times. Please see the ACT test for more information. 

Heparinized hematocrit capillary tubes: Primarily used for exotic species (minimum of 5 required for avian/ exotic chemistry). Please seal only one end of the tube.

Histopathology jars: Two sizes of histopathology jars are available. Please make sure to package in leak proof bag separate from other samples. Formalin fumes will destroy slides for cytology.

Blood culture vial and bottle (Oxoid): (Available for charge). Vial vs. bottle will depend on how much blood can be safely obtained from the patient. A larger volume of blood minimizes the possibility of a false negative result. Smaller vials require 0.5-1.5ml of whole blood while the bottles require 5-10ml of blood. If submitting a vial, a single vial is sufficient for aerobic and anaerobic culture. If submitting bottles, please submit two per patient (one for aerobic and one for anaerobic). Please see the blood culture protocol.

Calgiswab (Puritan): Primarily for obtaining samples from small orifices ex. in avian species.

Cary-Blair media (Remel): Bacterial transport media, useful for culture of enteric pathogens such as Salmonella and Campylobacter (make sure sample arrives at the lab as soon as possible, within 24 hour of collection).

Culturette swabs (Aimes media; mwe): Aerobic culture from wounds, discharge, ears. Anaerobes can also be isolated in most cases if the sample is transported to the lab rapidly. The swab itself is suitable for most PCR analysis, but cannot be placed into the culture media. If using the swab for PCR testing, swab the site, snip off the shaft, and place the swab in a no additive tube.

SAF (Sensor health): This fixative helps to preserve the morphology of intestinal parasites such as Giardia.

Viral culture media (Puritan UnitTranz-RT transport system): For transport of viruses, Chlamydophila, Mycoplasma and Ureaplasma.

PCR swabs: These polyester applicator swabs with plastic handles are preferred to cotton swabs for PCR testing.

Other supplies available upon request include: Requisition and supply order forms, plastic bags, slide holders, styrofoam mailers, pre-paid Purolator waybills, Purolator pouches, wellness brochures, and ice packs.

For other supply inquiries please call the lab.


TNVD uses a combination of company and independent contract couriers to service the Lower Mainland and Fraser Valley areas, and commercial couriers for all remaining areas of the province and beyond. Clients in the Lower Mainland and Fraser Valley are eligible for 2 to 3 pick-ups per day Monday to Friday, one to two pick-ups on Saturday, and one pick up Sunday. Cut-off times will be assigned to each clinic, and clinics will be eligible for a pick up if a request is made prior to the cut-off time for the particular courier run. Calls for pick-ups are made to the Langley laboratory at 604-539-5550 or 1-877-539-5550. Samples can also be dropped off with a completed requisition form at the Langley laboratory during business hours which are as follows:

Monday to Friday: 8am-10pm
Saturday: 9am-10pm
Sunday: 12pm-7pm Sunday;
All statutory holidays excepting Christmas Day: 12pm-4pm