Creating a Stable Short-term Housing Environment for Rabbits in a Cargo Van.

A stable environment is a prerequisite for animal research. The absence of a suitable laboratory rabbit environment at thegyrotron facility, with the nearest housing being 6.3 miles away, made it challenging to investigate ocular damage inducedin rabbit eyes due to exposure to high-frequency millimeter waves. Because rabbits are prone to transportation stress, it wasvital to keep them on-site during research. Here we describe the creation of the stable environment necessary to performreliable and reproducible animal experiments, by using a cargo van parked at the gyrotron facility. To control the interiorenvironment, we placed a window air conditioner, humidifier, dehumidifier, and photocatalyst deodorizer inside the cargoarea without altering the original configuration of the vehicle. Rabbits were housed in individual cages for a maximum of 6d. Microbial contamination in the air was evaluated by using a passive sampling method. The average numbers of bacterialand fungal colony forming units per dish were 0.2 and 4.7, respectively, indicating that the van was as clean as a nonbarrieranimal facility. The average temperature was 20.5 °C (range, 17.8 to 22.6 °C), and the average relative humidity was 49.4%(range, 36.2% to 63.2%). The concentration of ammonia was consistently below the detection limit of 0.5 ppm. Other environmental conditions were within appropriate levels. Rabbits lost 6.4% ± 2.2% (n = 52) of their initial body weight duringthe 13- to 14-h transport but recovered the lost weight within 48 h after arrival.