July 2020 Newsletter: Of Mice and Men

In the world of medical testing, the rodent testing stage is critical in the development of new drugs. With the need for speedy drug development at an all-time high, the demand for improving efficiency at this stage has also increased. Reliable laboratory experiments call for the elimination of as many variables as possible. Two environmental factors that may be overlooked are noise and vibration, which can cause stress in laboratory mice and rats. Read on to learn more about these factors.

Acute and chronic stress can have detrimental effects on laboratory mice at all stages of life. During the breeding stage, stressors can lead to longer reproduction times and lower pup count. Some species of rats, when exposed to acute audio stress during young stages of development, will develop lifelong audiogenic seizures. When exposed to acoustic stressors, rodents typically exhibit increased cortisol levels which drastically alter how medication is processed and can significantly change experimental results. This hinders the repeatability and reproducibility of experiments, which slows down the entire drug research cycle.

The National Institutes of Health (NIH) is acutely aware of this problem and has highlighted the need for continuous monitoring of extrinsic environmental factors in research. As outlined in NIH Office of Research Infrastructure Programs Executive Summary of RFI: NOT-OD-17-011:

Overall, underreporting of environmental conditions in metadata associated with experimental data is a compelling issue. Responders agreed that environmental parameters must be monitored and recorded to augment experimental data, making them more valuable for future use.

Without this knowledge and mitigation of environmental factors, it is impossible to ensure repeatability among experimental outcomes.

Traditional methods of diagnosing noise and vibration problems include taking spot measurements, which is the practice of recording data over a short time period. Spot measurements can be performed for sound, vibration, temperature, and other environmental factors. While general background and typical use cases are captured, spot measuring has significant limitations. Seasonal changes in equipment; transient sources such as trains, trucks, or neighboring construction; or degradation of lab equipment itself may not be captured with this monitoring strategy. Transient sources can raise ambient noise levels to 80 dB with exceedances greater than 100 dB. Such levels can cause stress in rodent test subjects.

A continuous system that monitors vibration, audible sound, and ultrasonic intrusions can help identify environmental factors that may stress laboratory animals and allows managers to react swiftly to any adverse changes detected. A quick response benefits any experimental environment by reducing downtime and saving money. Results from data collected in an experiment that has had continuous environmental monitoring have a reduced risk of being invalidated by environmental factors. Adding a fully automated continuous monitoring and reporting system to your lab can save you money, make things easier for your staff, and improve the scientific rigor of your results.
Metropolitan Acoustics has been hard at work developing an easy-to-use continuous monitoring platform for environmental factors including sound and vibration. We look forward to bringing you more news about it soon. Stay tuned!
June 2020 Newsletter: I Feel The Earth Move