2017 ACVIM Forum Research Abstract Program

Urine was collected over a 24 hour period from one mildly proteinuric and one severely proteinuric dog each with negative urine cultures and a unremarkable urine sediment and stored at 4°C in a homopolymer propylene collection jug designed for 24-hour urine protein analysis in humans. Five aliquots of each urine sample were subjected to each of nine storage conditions: in three types of container (glass, propylene copolymer, and homopolymer propylene) at either 24°C for 4 hours, 4°C for 12 hours, or À20°C for 72 hours. An additional five aliquots were stored at À80°C in homopolymer as a control. Following experimental storage, samples were then stored at À80°C in homopolymer until analysis. To determine the minimum size of each of the study groups, a power analysis was performed a priori. With a power of 80%, an alpha of 5%, and a standard deviation of 0.3 for severely proteinuric animals and 0.1 for mildly proteinuric animals (based on pilot study), 4 samples would be needed to detect an approximate 10% decrease in UPC in a severely proteinuric sample (from 10 to 9) and an approximate 33% decrease in the UPC in a mildly proteinuric animal (from 0.6 to 0.4). The latter was chosen as it would alter recommendations based on the 2005 ACVIM guidelines. Shapiro-Wilk test indicated that values were normally distributed. For each urine sample, ratios were compared using a one-way ANOVA with storage condition as the only factor in the model, and ratios were compared among treatments post-hoc with a Bonferroni correction (experimentwise type 1 error < 0.05).