
SONOTRACK is a new and non-invasive measurement method to monitor and analyze ultrasonic sounds produced by (laboratory) animals. Unlike many other systems that are based on bat detectors, SONOTRACK uses special microphones and hardware that can pick up sounds in the frequency range of 15KHz to 100 kHz. The sounds picked up by the microphones are not only converted to audible signals but the “complete ultrasound signal” is also recorded in digital format.
The unique graphical presentations of the signals in the SONOTRACK software enables the user to analyze the sounds or "animal language" in much more detail than ever before. The innovative Ultrasound Vocalization (USV) detector enables automatic detection and counting of ultrasonic vocalizations of your animals. The batch processing function of the USV detector makes it possible to go through a large amount of measurements and provide you quickly the end points of your experiment.
It is this unique functionality, which can lead to a further refinement of your research, with the following advantages:
In contrast to most of the other systems on the market SONOTRACK is a so-called full spectrum recording system. It means that it digitizes and records the whole ultrasound band from 15kHz to 100kHz. In contrast most of the other systems are based on bat detectors that have to be tuned to a specific frequency range and can only receive a small band that is approximately 15kHz wide. In applications involving rodents that vocalize over a broad frequency range it is obvious that these bat detectors systems are unsuitable.
The full spectrum recording technique makes it also possible to present the recordings in all kind of graphical presentations such as Sonograms which reveal a lot of information about the actual call or vocalizations of your animals.
To present detailed information about the recorded ultrasound signal, the following steps are applied:
Ultrasound vocalizations (USV), sometimes also called Ultrasonic vocalizations are commonly referred to as sounds within the frequency range of 20 kHz - 100 kHz. This frequency range is well above the human range of hearing. However, it is well known that bats, dolphins, rodents and insects produce and hear USV as part of their behavior.

There is evidence that USV is used as a sensitive indicator of subtle emotional and motivational changes in a number of animals. Therefore, USV produced by animals in various conditions could be explored as a non-invasive method for registering the welfare status of an animal.
Currently known rat and mice Ultrasonic Vocalizations
The use of USV to measure the welfare status of an animal can be advantageous in a number of situations:

Click on the movie symbol to see a MPEG movie about the use of ultrasonic communication between rats.
16 MB Video Clip (copyrights Oxford University - Dr. M. Berdoy)
The full movie and valuable information about the natural life of rats can be found on the Dr. M. Berdoy's website: www.ratlife.org.
Click on the movie symbol to see an AVI movie of a mouse mother responding on an 65 kHz ultrasound call of her pup that is away from the nest.
7 MB Video Clip (copyright Emory University - Liu Lab)
More information can be found on the respective website of Emory University. www.biology.emory.edu/research/Liu/html/index.php
Modern equipment transforms the USV sounds in a for humans audible signal ready for analysis. The very time-consuming and labor-intensive method with a bat detector combined with a tape-recorder is no longer an option for a versatile measurement. Research laboratory TNO in The Netherlands developed equipment that monitors USV sounds making use of special microphones, a PC (with A/D card) and software. Monitored USV sounds can directly be analyzed by means of several graphical presentations and the conversion of the signals to audible signals. An example of such a graph is provided in the picture on the right. The pictures presents the USV sounds generated by a mother and here pups.
| Click on the speaker symbol to play a few of the sound files that were recorded and converted to audible signals. Based on the original prototype of TNO, Metris and TNO produced the product SONOTRACK that has the ability to monitor the full ultrasonic spectrum (15kHz..100kHz) of four independent channels at the same time. |
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2010-04-05