A Practical, Noninvasive Urine Collection Method for Mice for Large Cohort Preclinical Studies

Area of Science:

• Preclinical research
• Animal models
• Urine sample collection

Background:

• Conventional urine collection methods in preclinical studies are often invasive, labor-intensive, and raise animal welfare concerns.
• Existing techniques are not easily scalable for large cohorts and can lead to sample contamination.
• There is a need for refined, noninvasive methods for accurate urine collection in mice.

Purpose of the Study:

• To develop and validate a noninvasive, practical technique for collecting spot urine samples from healthy and tumor-bearing mice.
• To refine existing urine collection approaches for improved animal welfare and experimental efficiency.
• To ensure collected urine volumes are sufficient for diverse molecular and metabolic analyses.

Main Methods:

• A novel technique involving positioning mice in a natural voiding posture with free-hanging hindlimbs and forelimb grip on a wire bar feeder.
• Gentle abdominal pressure applied as needed to facilitate voiding.
• Validation performed on 80 C3H/HeJ and athymic nude mice (healthy and tumor-bearing models).

Main Results:

• Reliable collection of spot urine volumes (13-200 µL) from all mice within 1 minute per sample.
• Successful first-attempt collection in approximately 70% of cases, with no significant difference in yield across groups.
• No observed fecal or particulate contamination; collected volumes adequate for molecular and metabolic analyses.

Conclusions:

• The presented technique is a practical refinement for preclinical urine sample collection, balancing sample quality, animal welfare, and efficiency.
• The noninvasive method is suitable for large cohort studies and repeated sampling due to minimal handling and no need for restraint devices.
• This approach enhances the reliability and scalability of urine collection in preclinical research settings.