Influence of animal husbandry practices on void spot assay outcomes in C57BL/6J male mice.
OBJECTIVE
Mice are increasingly being used as models to investigate aspects of urinary dysfunction that humans with lower urinary tract symptoms (LUTS) experience. One method used to examine voiding function is the spontaneous void spot assay. The purpose of this study was to characterize and identify animal husbandry conditions that might confound results of the spontaneous void spot assay in male C57Bl/6J mice.


METHODS
Mice were placed in cages lined with filter paper for 4 hr and urine was visualized with UV transillumination. Voiding parameters including urine spot number, spot size, total urine area, primary void area, corner and center voiding were quantified.


RESULTS
Adult male mice void more frequently with advancing age and a subpopulation (5-10%) display a frequent spotting pattern at 6-9 weeks of age. Voiding was not significantly different in male mice weaned to group housing (4-6 per cage) versus single housing, and was not altered when they were used as breeders. Voiding was changed upon transferring group housed adult males to single density cages, which decreased total urine area. Repeated assays of male voiding behavior over three consecutive days increased primary void area by the third day of monitoring and revealed that voiding behavior is impacted by routine cage changes and time of day.


CONCLUSIONS
Together these results identify housing and husbandry practices that influence male voiding behaviors in the spontaneous void spot assay and will inform voiding behavior analyses conducted with male C57Bl/6J mice.
Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin.
Kimberly P
KP
Keil
Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin.
Lisa L
LL
Abler
Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin.
Helene M
HM
Altmann
Department of Urology, University of Wisconsin, Madison, Wisconsin.|Carbone Cancer Center, University of Wisconsin, Madison, Wisconsin.
Wade
W
Bushman
Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, Wisconsin.
Paul C
PC
Marker
Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, Wisconsin.
Lingjun
L
Li
Department of Urology, University of Wisconsin, Madison, Wisconsin.|Carbone Cancer Center, University of Wisconsin, Madison, Wisconsin.
William A
WA
Ricke
Department of Urology, University of Wisconsin, Madison, Wisconsin.|Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin.
Dale E
DE
Bjorling
Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin.
Chad M
CM
Vezina
D000367:Age Factors; D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D001522:Behavior, Animal; D002940:Circadian Rhythm; D003950:Diagnostic Techniques, Urological; D006234:Handling, Psychological; D006799:Housing, Animal; D008297:Male; D008810:Mice, Inbred C57BL; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013997:Time Factors; D014554:Urination; D014563:Urodynamics
bladder; filter paper; lower urinary tract; prostate; void spot assay