Urinary stones formed into the shape of a flower.

G.V. Ling Urinary Stone Analysis Laboratory

About the Lab

Originally opened in 1981, the G.V. Ling Urinary Stone Analysis Laboratory was an early pioneer and specialist in companion animal urinary stones, which can differ greatly in both appearance and mineral composition from human stones. Stone analysis provides key stone compositional information that can be critical for establishing why the stones originally formed and what management techniques could prevent their future recurrence. Through a holistic investigation of the relationship between diet, environmental and patient factors, and urinary tract condition, we aim to advance the science of urinary tract health.

All analyses and veterinary consultations are completely free of charge, thanks to generous support from Purina PetCare. Currently the stone lab provides urinary stone analysis services for dogs and cats.

Submitting Samples

To submit a sample, fill out the submission form and send to us via the shipping instructions (click below). We recommend opening the form (pdf) link in a new window tab.

Stone Sample Submission Form

Shipping Instructions

All stones should be submitted clean and dry in a labelled and non-breakable container. Ideally all removed stones should be submitted for analysis – if this is not possible, a representative sample of shapes and sizes should be sent. Samples as small as 1mm can be analyzed.

If stones are clean and dry, they may be stored and shipped at room temperature. Samples should NOT be stored in formalin or any other liquid. Inappropriate storage or submission can delay stone analysis or lead to ambiguous results.

Send completed form and sample to:
UC Davis VMTH
Central Laboratory Receiving, Room 1033, 1 Garrod Dr
Davis, CA 95616

For quicker results, please send the specimens via Fed Ex or expedited shipping. We usually have reports available within 2-5 business days of receiving the sample.

For questions, contact us:
530-760-9209 | stonelab@ucdavis.edu
530-752-VMTH (8684) | UCDVetClinicalLabs@ucdavis.edu

About Urinary Stones

A urolith diagram.

Urinary calculi, or uroliths, are mineral deposits found within the urinary tract. The composition of these stones can vary widely according to etiology – not only can there be multiple urolith types present within the same animal, but a single stone may also differ in composition between the surface layer, the interior layers (of which there may be multiple) and the center nidus of the urolith. Alternatively, a urolith may be completely homogenous, where the entirety of the stone is of a single mineral composition and there are no noteworthy distinctions between parts of the stone.


Our Diagnostic Methods

The stones are first examined under a dissecting microscope for any distinguishing characteristics on the surface or cross-sectional textures. Afterwards crystals are inspected with a polarizing microscope and identified by the oil immersion method of optical crystallography, based on features such as refractive index, birefringence, and crystal shape. When necessary, additional analysis of the uroliths is conducted utilizing Fourier transform infrared spectroscopy (FTIR) and other specialized technologies such as X-ray diffraction.

Urinary stone analysis is typically completed within one week, allowing ample time to create a management plan for when patients are seen for post op checkups.
 


Lab Personnel
 

Jodi Westropp
Jodi L. Westropp DVM, PhD, DACVIM

Director

Samantha Barnum
Samantha Barnum, MS

PCR Lab Supervisor 

Angelica Kallenberg
Angelica Kallenberg

Staff Researcher
 


Our Research

Stone analysis at the G.V. Ling Stone Analysis Laboratory has resulted in numerous presentations as well as peer reviewed manuscripts. Not only have these been in the form of retrospective studies that examine breed- or population-level differences or chronological trends, but also technical notes on stone analysis that further the field.

All stones submitted to the VMTH Clinical Diagnostic Laboratories may be used for VMTH teaching and research purposes consistent with the mission of the University. Please contact the Stone Lab directly at stonelab@ucdavis.edu regarding potential collaborative studies.


Our Mission

The G. V. Ling Urinary Stone Analysis Laboratory is dedicated to provide reliable, accurate and prompt layer by layer stone analyses for our clients. We strive to maintain the most current scientific techniques available for these analyses for clinical and research endeavors. Furthermore, we are committed to helping veterinarians manage their patients. We use science, technology and education as our tools.


  • FAQs
  • Q:  Can any veterinarian or animal laboratory send samples to the G.V. Ling Urinary Stone Analysis Laboratory at Davis?

    A:  Yes, we receive samples from veterinary practices and laboratories from all over the United States as well as several foreign countries.


    Q:  How much is a stone analysis at UC Davis?

    A:  Stone analysis is free of charge, made possible by generous support from Purina Petcare.


    Q:  How long will it take for me to obtain the results?

    A:  We have most stone analysis reports prepared within 2 to 5 days of receiving the sample.


    Q:  Can any pet owners submit stones they have obtained from their pets directly to the G.V. Ling Urinary Stone Analysis Laboratory?

    A:  No, samples must come from a veterinary practice or animal laboratory.  By working with your veterinarian, we will be able to help you both tailor a proper stone prevention strategy for your pet.


    Q:  Do I need to put the stone in formalin in order to send it to you?

    A:  No. Stones should be sent clean and dry. While formalin should not hurt most stones, exposure to formalin can affect struvite stones and can change the surface crystals from struvite to newberyite. Additionally, the formalin will need to be removed prior to analysis, delaying results, and shipping a stone in formalin requires extra care and packaging to ensure safe shipping.


    Q:  Does your laboratory analyze stones removed from human beings?

    A:  No. We are not licensed to analyze stones from humans.


    Q:  Should I send all the stones I have removed from the animal?

    A:  The composition can vary from stone to stone, so at minimum a representative sample of shapes and sizes should be sent.


Contact

530-760-9209 | stonelab@ucdavis.edu
530-752-VMTH (8684) | UCDVetClinicalLabs@ucdavis.edu