BACKGROUND: There are currently few reports on the normal urinary protein-to-creatinine (UPC) ratio of guinea pigs, and there is little information on the effects of age and sex on this parameter. METHODS: Urinary protein and creatinine concentrations were measured in a total of 161 clinically healthy guinea pigs, and the UPC ratio was subsequently calculated. The effect of age and sex on these parameters was assessed using Mann-Whitney U tests. Using these data, UPC ratio reference ranges were established. RESULTS: Guinea pig pups younger than 6 months had a significantly higher UPC ratio than adult animals (median UPCs of 1.48 and 0.56, respectively). There was no effect of sex on this parameter. The reference range for the UPC ratio in adult guinea pigs was set at 0.12-2.21. For guinea pigs younger than 6 months, the reference range for the UPC ratio was set at 0.4-3.1. LIMITATIONS: This study was limited by the lack of blood analysis, which could reveal a subclinical health problem that could affect renal function and the extent of proteinuria. CONCLUSION: In guinea pigs, the UPC ratio is influenced by age but not by sex. Therefore, the reference range established for adult guinea pigs cannot be used for pups younger than 6 months.

Department of Animal Protection and Welfare and Veterinary Public Health Faculty of Veterinary Hygiene and Ecology University of Veterinary Sciences Brno Brno Czech Republic

Department of Pharmacology and Pharmacy Faculty of Veterinary Medicine University of Veterinary Sciences Brno Brno Czech Republic

Jekl and Hauptman Veterinary Clinic Brno Czech Republic

Zobrazit více v PubMed

Minarikova A, Hauptman K, Jeklova E, Knotek Z, Jekl V. Diseases in pet guinea pigs: a retrospective study in 1000 animals. Vet Rec. 2015;177(8):200. PubMed

Holowaychuk MK. Renal failure in a guinea pig (Cavia porcellus) following ingestion of oxalate‐containing plants. Can Vet J. 2006;47(8):787‒789. PubMed PMC

Hawkins MG, Ruby AL, Drazenovich TL, Westropp JL. Composition and characteristics of urinary calculi from guinea pigs. J Am Vet Med Assoc. 2009;234(2):214‒220. PubMed

Bays TB. Geriatric care of rabbits, guinea pigs, and chinchillas. Vet Clin North Am Exot Anim Pract. 2020;23(3):567‒593. PubMed

Reavill DR, Lennox AM. Disease overview of the urinary tract in exotic companion mammals and tips on clinical management. Vet Clin North Am Exot Anim Pract. 2020;23(1):169‒193. PubMed PMC

Fisher PG. Exotic mammal renal disease: diagnosis and treatment. Vet Clin North Am Small Anim Pract. 2006;9(1):69‒96. PubMed

Schmid NS, Clauss M, Hetzel U, Riond B, Bochmann M, Hatt JM. Development, diagnosis and therapy of ketosis in non‐gravid and non‐lactating Guinea pigs. BMC Vet Res. 2020;16(1):41. PubMed PMC

Grauer GF. Proteinuria: measurement and interpretation. Top Companion Anim Med. 2011;26:121‒127. PubMed

Hoskins JD, Turnwald GH, Kearney MT, Gossett KA, Fakier N. Quantitative urinalysis in kittens from four to thirty weeks after birth. Am J Vet Res. 1991;52:1295‒1299. PubMed

Miyazaki M, Kamiie K, Soeta S, Taira H, Yamashita T. Molecular cloning and characterization of a novel carboxylesterase‐like protein that is physiologically present at high concentrations in the urine of domestic cats (Felis catus). Biochem J. 2003;370:101‒110. PubMed PMC

Schäfer‐Somi S, Bär‐Schadler S, Aurich JE. Proteinuria and immunoglobulinuria in neonatal dogs. Vet Rec. 2005;157:378‒382. PubMed

Bertieri MB, Lapointe C, Conversy B, Gara‐Boivin C. Effect of castration on the urinary protein‐to‐creatinine ratio of male dogs. Am J Vet Res. 2015;76:1085‒1088. PubMed

Kovarikova S, Zivotska N, Blahova J. Urine protein to creatinine ratio (UPC) in puppies and young dogs. J Vet Intern Med. 2020;34:3149‒3150.

Rossi G, Bertazzolo W, Dondi F, Binnella M, Gruarin M, Scarpa P, et al. The effect of inter‐laboratory variability on the protein:creatinine (UPC) ratio in canine urine. Vet J. 2015;204:66‒72. PubMed

Rossi G, Bertazzolo W, Binella M, Scarpa P, Paltrinieri S. Measurement of proteinuria in dogs: analytic and diagnostic differences using 2 laboratory methods. Vet Clin Pathol. 2016;45:450‒458. PubMed

Vientós‐Plotts AI, Behrend EN, Welles EG, Chew DJ, Gaillard PR, Busler JN, et al. Effect of blood contamination on results of dipstick evaluation and urine protein‐to‐urine creatinine ratio for urine samples from dogs and cats. Am J Vet Res. 2018;79(5):525‒531. PubMed

Jillings E, Squires RA, Azarpeykan S, Lopez‐Villalobos N. Does blood contamination of urine compromise interpretation of the urine protein to creatinine ratio in dogs? N Z Vet J. 2019;67(2):74‒78. PubMed

Giraldi M, Paltrinieri S, Rossi G, Ruggerone B, Zambarbieri J, Ercolani A, et al. Influence of preanalytical factors on feline proteinuria. Vet Clin Pathol. 2021;50(3):369‒375. PubMed

Kennils JM, Maunder CL, Costa MT. The effect of non‐absorbent hydrophobic sand litter on the urine protein‐to‐creatinine ratio in feline urine. Vet Clin Pathol. 2022;51(3):385‒390. PubMed PMC

Mortier F, Daminet S, Duchateau L, Marynissen SJJ, Paepe D. Comparison of cystocentesis versus home sampling to determine urinary protein:creatinine ratio and urine specific gravity in cats. J Vet Intern Med. 2023;37(4):1401‒1408. PubMed PMC

Yalamati P, Karra ML, Bhongir AV. Comparison of urinary total proteins by four different methods. Indian J Clin Biochem. 2016;31:463‒467. PubMed PMC

Rueloekke ML, Spangsberg R, Koch J. Establishment of normal values of urine protein/creatinine ratio in pet guinea pigs (Cavia porcellus). Proceedings of BSAVA Congress. Birmingham, UL: British Small Animal Veterinary Association; 2016. p. 554.

Cernochova H, Hundakova A, Bardi E, Knotek Z. Biochemical profile of urine in guinea pigs (Cavia porcellus). Vet Med. 2020;10:445‒450.

Heller J, Capek K. Changes in body water compartments and inulin and PAH clearance in the dog during postnatal development. Physiol Bohemoslov. 1965;14:433‒438. PubMed

Horster M, Valtin H. Postnatal development of renal function: micropuncture and clearance studies in the dog. J Clin Invest. 1971;50:779‒795. PubMed PMC

Merlet‐Benichou C, Pegorier M, Muffat‐Joly M, Augeron C. Functional and morphologic patterns of renal maturation in the developing guinea pig. Am J Physiol. 1981;241:F618‒F624. PubMed

Kovarikova S, Blahova J, Rehakova K. Comparison of two quantitative methods for urine protein measurement used for calculation of urine protein to creatinine ratio (UPC). J Vet Intern Med. 2020;34:3150.