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.
The laboratory provides urinary stone analysis for all animal species except primates, with the following pricing:
Canine & Feline Urinary Stone Analysis: FREE
Made possible through generous support from Purina PetCare. Veterinary consultations are also provided free of charge.
Other Species Urinary Stone Analysis (Except Primates): $193.00*
Includes analysis of up to three stones.
*Prices subject to change without notice. Updated 10/30/2026.
Submitting Samples
To submit a sample, fill out the appropriate submission form based on the patient's species and include the completed form with the sample.
Dog & Cat Stone Sample Submission Form
Stone analysis for canine and feline patients is provided free of charge through generous support from Purina PetCare.
All Other Animal Species (Except Primates) Stone Sample Submission Form
Stone analysis is available for all other eligible animal species, excluding primates, for a fee. Please indicate "Urinary Stone Analysis" under Test(s) Requested on the general submission form.
Shipping Instructions
All stones should be submitted clean and dry in a labeled, 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.
Stones 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 specimens via expedited shipping. We usually have reports available within 5–7 business days of receiving the sample.
For questions, contact us:
530-760-9209 | [email protected]
530-752-VMTH (8684) | [email protected]
About Urinary Stones
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 5–7 business days of sample receipt, allowing ample time to create a management plan for when patients are seen for post op checkups.
Lab Personnel
Jodi L. Westropp DVM, PhD, DACVIM
Director
Samantha Barnum, MS
PCR Lab Supervisor
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 [email protected] regarding potential collaborative studies.
- Clinical Trials
- • Dogs with Calcium Oxalate Stones
• Dogs with Urinary Tract Infections - Select Publications
2018 Paßlack N, Zentek J, Larsen JA, Westropp JL, Fascetti AJ Impact of hyperlipidaemia on intermediary metabolism, faecal microbial metabolites and urinary characteristics of lipoprotein lipase deficient vs. normal cats J Anim Physiol Anim Nutr (Berl),
2018 Segev G, Sykes JE, Klumpp DJ, Schaeffer AJ, Antaki EM, Byrne BA, Yaggie RE, Westropp JL Evaluation of the Live Biotherapeutic Product, Asymptomatic Bacteriuria Escherichia coli 2-12, in Healthy Dogs and Dogs with Clinical Recurrent UTI J Vet Intern Med,
2017 Merkel LK, Lulich J, Polzin D, Ober C, Westropp JL, Sykes J Clinicopathologic and Microbiologic Findings Associated with Emphysematous Cystitis in 27 Dogs JAAHA. (pdf)
2017 Westropp JL, Larsen JA, Johnson EG, Bannasch D, Fascitti AJ, Biourge V, Queau Y Evaluation of dogs with genetic hyperuricosuria and urate urolithiasis consuming a purine restricted diet: A pilot study BMC Vet Res,
2017 Kent MS, Zwingenberger A, Westropp JL, Barrett LE, Durbin-Johnson BP, Ghosh P, Vinall RL MicroRNA profiling of dogs with transitional cell carcinoma of the bladder using blood and urine samples BMC Vet Res. (pdf)
2016 Mellema M, Stoller M, Queau Y, ho SP, Chi T, Larsen JA, Passiack N, Fascetti AJ, Mohr C, Westropp JL Nanoparticle tracking analysis for the enumeration and characterization of mineralo-organic nanoparticles in feline urine PLoS One.
2016 Lulich JP, Berent AC, Adams LG, Westropp JL, Bartges JW, Osborne CA ACVIM Small Animal Consensus Recommendations on the treatment and prevention of uroliths in dogs and cats J Vet Intern Med. - (pdf)
2016 Palm CA, Segev G, Cowgill L, LeRoy B, Kowalkowski KL, Kanakubo K, Westropp JLUrinary neutrophil gelatinase-associated lipocalin as a marker for acute kidney injury identification and recovery in dogs with Gentamicin-induced nephrotoxicity J Vet Int Med.
2015 Keller KA, Hawkins MG, Weber SEP, Ruby AL, Sanchez-Migallon Guzman D, Westropp JL Diagnosis and treatment of urolothiasis in client owned chelonians: 40 cases (1987-2012) J Am Vet Med Assoc.
2015 Safra N, Hayward LJ, Aguilar M, Sacks BN, Westropp JL, Mohr CF, Mellersh CS, Bannasch DL DNA sequence variants in the five prime untranslated region of the cyclooxygenase-2 gene are commonly found in healthy dogs and gray wolves PLoS One.
Low WW, Uhl JM, Kass PH, Ruby AL, Westropp JL. Evaluation of trends in urolith composition and characteristics of dogs with urolithiasis: 25,499 cases (1985-2006). JAVMA 15(236): 193-200, 2010. (pdf)
Cannon AB, Westropp JL, Ruby AL, Kass PH. Evaluation of trends in urolith composition in cats: 5,230 cases (1985-2004). JAVMA, 231(4): 570-6, 2007. (pdf)
Westropp JL, Ruby AL, Bailiff NL, Kyles AE, Ling GV. Dried solidified blood calculi in the urinary tract of cats. JVIM, 20(4): 828-34, 2006. (pdf)
ACVIM consensus statement Recommendations for Urolithiasis. (pdf)
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 throughout the United States as well as several foreign countries. We accept urinary stone submissions from all animal species except primates.Q: How much is a stone analysis at UC Davis?
A: Stone analysis for dogs and cats is free of charge, made possible by generous support from Purina PetCare. For all other species, the fee is $193.00*, which includes analysis of up to three stones.Q: How long will it take for me to obtain the results?
A: We have most stone analysis reports prepared within 5 to 7 business 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 submitted clean and dry without formalin or other liquids. While formalin should not affect most stones, exposure to formalin can affect struvite stones and change the surface crystals from struvite to newberyite. Additionally, formalin must be removed before analysis, which can delay results. Shipping stones in formalin also requires additional care and packaging.Q: Does your laboratory analyze stones removed from human beings?
A: No. We are not licensed to analyze stones from humans. We also do not accept submissions from nonhuman primates.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
G.V. Ling Urinary Stone Analysis Laboratory
530-760-9209 | [email protected]
VMTH Clinical Diagnostic Laboratories
530-752-VMTH (8684) | [email protected]
Send samples with a completed submission form to:
UC Davis VMTH
Central Laboratory Receiving, Room 1033
1 Garrod Dr.
Davis, CA 95616
Submission Forms:
G.V. Ling Urinary Stone Analysis Laboratory Submission Form – Dogs and Cats
Clinical Diagnostic Laboratories General Sample Submission Form – All Other Eligible Species
We recommend mailing clean, dry samples via FedEx or UPS in a labeled, non-breakable container.
Use of Submitted Samples and Information
Biological samples and information submitted to the UC Davis VMTH Clinical Diagnostic Laboratories may be used for teaching and research purposes consistent with the mission of the University.
Residual stone material remaining after diagnostic testing may be retained and used for research, educational, quality improvement, statistical, or other academic purposes. Information provided with a submission may also be used to support these activities.
When submitted samples or information are used for research, identifying information will be removed or de-identified whenever appropriate. Publications, presentations, or other reports resulting from these activities will not identify individual patients, animal owners, veterinary practices, or submitting veterinarians.