In zoological collections, sterile urine samples can be difficult to acquire and samples often are obtained from the floor. The aim of this study is to assess how contact time with substrates (hay, soil, mulch), cleaners, floors, feces, and food affect the validity of urinalysis for clinical decision-making. The first phase of the study involved dipstick analysis of sterile water following contact with surfaces and substrates.2 Sterile water samples were either allowed immediate or extended contact with surfaces or substrates. The second phase of the study involved urinalysis from a commercial laboratory and dipstick analysis of sterile urine samples from an ocelot (Leopardus pardalis), a ringtail cat (Bassariscus astutus), and two Asian elephants (Elephas maximus) following immediate and extended contact with a variety of surfaces and substrates. The study results concluded that both immediate and extended contact with meat and meat juice altered protein, bilirubin, RBC, and WBC results. On dipstick analysis, contact with vegetable mix elevated glucose readings and contact with dirt consistently elevated nitrite levels. On urinalysis, contact with feces increased occult blood, bacteria, protein, and glucose. Overall, contact with wood, metal, concrete, and cleaners had minimal affects on analysis. Microalbumin results were variable in urine samples following contact with surfaces and substrates and require further evaluation along with urine protein creatinine ratios to determine their validity. While this may be the first study to evaluate urine contamination impacts on urinalysis, a number of published accounts demonstrate the importance and significance of urinalysis for patient care.1
The authors offer a special thanks to the animal care staff, veterinary technicians, and hospital staff at the San Antonio Zoo for their help and financial support with this project.
1. Callens AJ, Bartges JW. Urinalysis. Vet Clin North Am Small Anim Pract. 2015;45:621–637.
2. Siska WD, Meyer DJ, Schultze AE, Brandoff C. Identification of contaminant interferences which cause positive urine reagent test strip reactions in a cage setting for the laboratory-housed nonhuman primate, beagle dog, and Sprague-Dawley rat. Vet Clin Pathol. 2016;46(1):85–90.