If you are checking on a sample status - login at our website. If the status of the samples is still listed as "Not Yet Received" please check with your shipping company before contacting us.

Once the package is opened it will be marked as "Pending". Our average in-lab turnaround time is posted at urolithcenter.org. Some samples require additional testing so please allow 1-2 weeks.

Results: We email or fax the results to your clinic, so please verify that your email information on your account is valid and current. Occasionally, our email can end up in your junk/spam folder, so check those folders if you have not received the results to your in box. You can also view results online at urolithcenter.org for one year after they have been completed.

Account questions

Expand all

I encounter an email and password error when trying to login. How do I login?

Please email us with your clinic name, address and login username and we can email your clinic account information.  If you do not know your login password - go to Forgot Password to have a new password sent to you.

What should I do if I forgot my password?

If you do not know your login password - go to Forgot Password to have a new password sent to you

How do we update our clinic contact information?

If you need to updated your clinic email, phone, fax or user information see Managing your online account and clinic information (pdf). For change of clinic address - please email us. Include your old and new information and we will update your account. 

What can I submit?

Expand all

Can I submit a urethral plug for analysis?

How to submit feline/canine urethral plugs:

Urethral Plugs may be:

  • Composed primarily of crystalline material.
  • Composed primarily of cellular/proteinaceous material.
  • Composed of an admixed population of crystalline and cellular/proteinaceous material.

Our quantitative analysis techniques can identify the crystalline components in the sample.

If you would like identification of the cellular components, we suggest you split the sample, and send a formalin preserved portion to your preferred histopathology service.

Please submit urethral plugs to our laboratory dry in an unbreakable container.

What samples are accepted/declined?

Our laboratory offers urolith analysis of minerals from the urinary tract (aka uroliths, urinary stones, urinary calculi).

Samples not accepted
Urolith cultures, urinalysis, choleoliths (gallbladder stones), sialoliths, enteroliths or other material from outside the urinary tract are not accepted. Consult your local reference laboratory, your state veterinary college or diagnostic laboratory, or materials characterization facilities in your area for assistance

Where can I submit a urolith for culture?

At the Minnesota Urolith Center we perform quantitative urolith analysis which indicates the mineral type(s) in the urinary calculi. We do not offer urolith culture as part of our no-cost urolith analysis. However, the University of Minnesota Veterinary Diagnostic Lab does perform urolith culture for a cost.

If you only have one urolith, it can be both culture and quantitatively analyzed. Submission forms for both the Minnesota Urolith Center and the Veterinary Diagnostic Laboratory should be filled out and sent with a solitary urolith. The culture needs to be performed first. Send both sets of forms and the sample to the Veterinary Diagnostic Laboratory. You will need to include very specific instructions such as:

Note: Only one urolith. Please perform urolith culture first. Then please transfer sample to the Minnesota Urolith Center for analysis.

If you have more than one urolith, please either ship samples separately to each lab, or use inner packages to separate the samples and write on the outside "urolith for culture to the VDL" and "urolith for analysis to the MUC".  These two packets can then be placed in one outer package, shipped to the Minnesota Veterinary Diagnostic Laboratory or to the Minnesota Urolith Center to minimize shipping costs.

If you have additional questions regarding urolith cultures and charges please contact the Minnesota Veterinary Diagnostic Lab at 1-800-605-8787, or access their website for appropriate forms.

What species are samples accepted from?

USA submissions

We are able to accept samples from all species (except primates and humans) . Be sure to provide detailed species identification when entering patient information online prior to shipping samples.

International submissions

To comply with international regulations, shipments from clinics outside the United States must contain only approved species. See Shipping from outside the USA for acceptable species under USDA guidelines 1102, 1103, 1104. In general, dogs, cats, rodents, aquatic species, and reptiles are accepted.

What if I have multiple stones?

We advise always submitting the largest stone, and a representative portion of sizes, shapes, and colors. If uroliths were retrieved from different parts of the urinary tract; (e.g. kidney and bladder), send them in separate containers, identified with the source. All uroliths within a patient may or may not be composed of the same mineral type(s).

How small of a sample can be analyzed?

In most cases, if you can see the sample, we can analyze it. (Generally the size of a poppy seed). Please write tiny sample on the packing slip accompanying the sample.

How to submit

Expand all

Can I use a handwritten submission form?

We now require that all sample information be submitted online on our website. Information on how to setup an online account can be found on our urolith analysis page.

How do we package and ship the sample?

Detailed information can be found at Shipping a sample. We recommend you ship packages by a carrier that provides tracking information. Tracking provided by the shipping company gives you information on the path of your sample before it arrives in our laboratory. Submissions from outside the USA require shipping through carriers that allow for customs USDA/APHIS inspections.

Questions about uploading radiographs

  • When submitting sample information online, do I need to upload a radiograph image? No
  • How many radiographs/view can I upload when entering the sample information? One Lateral
  • What file format can be uploaded? png or jpeg
  • I forgot to upload the radiograph information when I entered the sample information - what should I do?  You can email the image to us. Be sure to include your clinic information along with the owner and patient name.

The sample was accidentally put in formalin, what do we do now?

If a sample is accidentally put in formalin and has not dissolved, you can remove the sample from formalin, rinse gently with water and allow to dry. Please note on the submission form that the sample has been in formalin. Sample analysis may be delayed due to inappropriate submission methods.

Can we ship samples from multiple patients in the same package?


  1. Enter the sample information online at urolithcenter.org
  2. Label each sample with the owner and patient name.
  3. Individually package each sample and paperwork together in a ziploc.
  4. Include a note with the number of samples in the package
  5. Ship the package via a trackable courier service.

After submission

Expand all

Can I cancel my sample? It has not been shipped...

Our online system does not allow you to cancel the analysis request. If the sample has not yet been shipped – please email us with your clinic name, address, owner/patient name along with our laboratory sample number and we can cancel the request.  

Can I cancel my sample? It is currently in the mail.

We are unable to cancel sample analysis once the sample has been shipped/received at the laboratory. The information entered for each sample provides epidemiological data that helps us track trends in mineral composition. You will receive a copy of the report.  We perform our analysis as no charge - so you will not receive a bill for our services. Owners are not contacted without the authorization of the submitting clinic. 

The submission form was not included in the shipment, what should I do?

Please email the laboratory with your clinic name, address and owner/patient information. We will watch for your sample and match it up with the online information when the sample arrives. 

The incorrect patient information was entered online. How do I correct it?

You are not able to edit sample information once it has been entered online. If you have not shipped the sample - please make the modifications to the submission slip and the changes can be made once the sample arrives at the laboratory. If you have already shipped the sample - please email us with your clinic and sample information and provide us with the correct data.

Results and how to interpret

Expand all

How are samples analyzed?

We perform quantitative mineral analysis utilizing Optical Crystallography and Infrared Spectroscopy (ATR and FTIR). For identification of unusual minerals, we have access to equipment and specialists on campus in techniques such as XRD, EDS, micro-CT, and other specialized methodology. Our highly trained technicians collectively have almost 125 years of experience in urinary mineral analysis.  Learn more about us.

How do I interpret the results?

View How to interpret (pdf) for a diagram and detailed information on how to interpret your results.

Can I view results from another clinic?

Consistent with data privacy policies, reports are transmitted only to the hospital/submitter designated on the urolith analysis request form. Therefore, we ask that you contact the submitting hospital for a copy of results. 

If this is not possible - we can also transmit results direct to the owner/or with the owner’s written permission we can provide results to your veterinary hospital. Please contact the laboratory with the owner/patient name, submitting clinic, approximate date of submission along with your clinic information and we will send you an authorization release form.

How do you release the results to a clinic?

When results are completed they are either emailed and/or faxed to the clinic depending on the notification method setup by the clinic. We no longer mail paper copies of results.

Can you provide a quality control/assurance letter?

Please contact us at 612-625-4221 or through email to request a copy of our current QC/QA letter.

Dietary questions

Expand all

Are treats/dental chews ok?

To our knowledge, no studies have been performed on the use of various treats and the impact on urolith formation. One suggestion is to use the kibble form of your selected canned prevention diet as treats. Some diet manufacturers have treats formulated to be used with select prescription diets. In most cases, if treats comprise less than 5-10% of the diet, they most likely will not affect prevention strategies to minimize urolith formation.

What home prepared diets are available for urolith management?

Creating a home-prepared diet for your specific pet requires the assistance of a board certified veterinary nutritionist. The American College of Veterinary Nutrition has a directory.

What's the best diet for urolith management?

See our management suggestions for specific urolith mineral types under Treatment Recommendations. Diets that we are familiar with using are listed on our prevention recommendations. Board certified veterinary nutritionists can assist in the formulation of a diet, make recommendations on commercial diets, discuss management of patients with multiple medical concerns, or consult on the appropriateness of a selected diet.If you would like to work directly with a veterinary nutritionist to identify a commercial diet for your specific pets needs visit: The American College of Veterinary Nutrition Diplomate Directory.   Some pet food companies have board certified nutritionists on staff to help you with selection of diet to fit individual patient's specific needs.