Development and testing of an automated food dispenser for small rodents.

An automated feeder system capable of delivering variable quantities of ground stock diet at predetermined time intervals was developed. The system consisted of feeder units activated by a solenoid connected to a sliding food chamber, a wiring harness, and a control unit. Testing for reproducibility of food delivery indicated reliable and consistent results with a coefficient of variation not exceeding 3% for multiple consecutive deliveries. Field testing in an actual feeding experiment with 35 rats in seven groups showed remarkable adherence to preset conditions. No untoward effects were observed when one group of free-eating, ad libitum fed rats was compared to another group fed unrestricted amounts of feed by the automated feeder. The feeder system was versatile, reliable, and easily adjustable to animal room environments.