Building a Better Rat Trap: Preferences of Rats for Foods and Semiochemicals
Kimberly Guay, Matthew May, Arlene Garcia, John McGlone
Texas Tech University, Lubbock.
Methods of capturing rats are relatively primitive and cost the agriculture industry three billion dollars every year. One way of improving the effectiveness of current traps would be to find foods and odors that either attract rats or cause them to avoid the area entirely; semiochemicals provide a unique solution by providing a chemical message that innately affects behavior. Rats were tested for their relative preference or aversion to food and semiochemicals in a Y-maze preference test consisting of an acclimation phase with Cheerios in the arms followed by a testing phase with odorants placed in arms behind a mesh with an airstream blowing over them into the arms of the maze. When various odors were tested against saline, isopropyl alcohol, and each other rats had strong general preferences for foods and spices (corn, soy, peanut butter, pig feed, milk replacer, black pepper, crush pepper), Talon Rat and Mouse Killer, and for the pig pheromone (Androstenone). Testing is underway to determine if androstenone makes current baits more attractive and can be used in commercial settings.
The Y-maze is intended to identify compounds that are either attractive or aversive to rats. Two compounds are placed in both arms (A,B) of the maze, with a wire mesh preventing the rat from consuming the compounds. The rat is then placed in the distal arm (C) and allowed to explore the arms for 45 seconds. The times spent in each arm are recorded and attraction or aversion to the compounds is determined
The open field was developed to give the study a more "real-life" approach. The open field is approximately 8ftx8ftx3ft. It allows the rats to walk around in the open field and explore the 3 bait boxes that are placed in each 90 degree corners. Substances that have been determined to be attractive or aversive to the rats are placed within the bait boxes. They are allowed to explore the open field for 2 minutes and times are then recorded. Compounds are then considered to potentially be an ingredient in rodenticides.