Chickens, Evaluation of SD 43775 Water Dispersible Liquid for the Control of Ornithonyssus Sylviarum (C&F) on Cage Layers, 1977

Chickens (200) with a heavy infestation of northern fowl mite were individually selected from a cage-layer house at Starkville, Mississippi. Population determination for initial selection and for rating throughout the test was scored on parting of the feathers in 3 areas below the vent. Scoring system used was: 0 = no mites, L = less than 10 mites, M = more than 10 mites, and H = mites too numerous to count. Scores were recorded for each bird at time of selecting birds, 1 week later, 1 day pre-treatment, 1 and 3 days posttreatment, and at weekly intervals for 9 weeks posttreatment. Three groups were treated with a 10% water dispersible liquid formulation of SD 43775. Group A (44 birds) a concentration of 0.0125% (a.i.), group B (43 birds) a concentration of 0.025% (a.i.), and group C (43 birds) was treated with a concentration of 0.05% (a.i.). Group D (41 birds) was treated with a concentration of 0.5% (a.i.) of 80% carbaryl WP.