The DAM2 Drosophila Activity Monitor measures the locomotor activity of 32 individual flies, each in a separate tube. As a fly walks back and forth within its tube, it interrupts an infrared beam that crosses the tube at its midpoint, and this interruption, detected by the onboard electronics, is added to the tube’s activity count as a measure of fly activity.
In a typical experiment, an agar/ sucrose food mixture is placed into one end of each tube, followed by the fly, and followed by a cotton plug in the open end. The 32 tubes are inserted into holes in the monitor case, and centered.
Over the course of the experiment, which may last for days or weeks, the counting circuits continuously monitor the activity in all 32 tubes, and at periodic intervals upload their count totals to the host computer for storage and later analysis. This daily record provides a good measure of both the intensity of locomotor activity and the relative periods of rest.
The DAM2 is fabricated from a transparent polycarbonate plastic, allowing light penetration to all points along the tube. It is compact, light in weight, and when used within an incubator, allows plentiful air circulation around the tubes. The throughhole design accommodates tubes of arbitrary length.
An on/off visible light sensor is built into each unit to provide a simple record of the ambient light state over time. This record accompanies the activity count data as it is acquired and stored, and is useful in analyzing circadian rhythms and adaptations of the flies to external light stimuli.
An optional gas distribution manifold is available to facilitate the controlled exchange of air within the tubes, as would be needed for hypoxia studies
Features • 32 tubes for 32 flies
• 5mm tube diameter for drosophila melanogaster, 7mm for d. virilis
• Consistent operation in bright room light or darkness
• Ambient light sensor provides on/off record of entrainment cycles, stimulation pulses, and inadvertent light exposure.
Specifications • Tube diameter: 5mm or 7mm
• Tube length: 65mm nominal, transparent glass or plastic
• Dimensions: 127 x 48 x 87 mm LWH
• Mass: 0.17 kg without tubes
• Ambient Light Sensor threshold: 10 lux nominal, photopic response curve
• Interconnect: 4 wire, 6 position, RJ-11 modular telephone line jack to PSIU9 DAMSystem network for 9V DC power input and data transmission
• Operating environment: normal laboratory, non-condensing