Insecticide Screening For Control of Chicken Lice, 1976

Chickens, naturally or artificially infested with the chicken body louse, Menacanthusstramineus (Nitzsch), were treated with acetone, ethanol, or water solution of compounds prepared from technical or finer grades. Material was applied by spraying 40 ml of solution onto the infested chickens with an artist's airbrush modified to give a coarse spray at a pressure of 40 psi. The chickens were suspended with a soft cotton rope by the legs and rotated to assure complete and adequate coverage. Treated animals were confined separately in cage-layer cells for a 28-day posttreatment observation period. Animals treated similarly were placed in adjacent cells, but those treated with different materials or concentrations were separated by one cell. Reinfestation, when it did occur, was limited to lice arising from viable eggs present on the test animals at time of treatment. Pretreatment louse populations were estimated by counting the motile forms found in 10 partings of feathers; 2 each at the vent, breast, back, neck, and wings. Posttreatment counts made in the same way were taken at 1, 3, 7, 10, 14, 21, and 28 days. If the initial test concentration of 0.25% Al was effective in controlling the lice ^90% reduction at 28 days posttreatment), subsequent tests were made at lower concentrations to determine the minimal effective dosage to achieve>90% reduction. A standard (0.01% malathion) and an acetone control were run with each series of tests. At least 2 animal replicates/concentration were treated. Methods of treatment and assessment of results were modified after R. A. Hoffman and B. F. Hogan, 1972, J. Econ. Entomol. 65(2): 468-70. Compounds were rated according to the following classifications based upon examination at 28 days posttreatment.