| Abstrakt: |
. Four sampling methods were compared to determine their practicality and suitability for detecting population fluctuations of adult Drosophila repleta, a pest in caged-layer poultry houses. Five caged-layer poultry houses with gutter-flush manure removal systems in Franklin County, North Carolina, U.S.A., were sampled once every 2 weeks over 15 months, from June 1991 to August 1992. The flies were most abundant during the spring and early summer. Visual counts of adult flies resting on the feed troughs in front of cages in the aisles and counts of flies caught on a sticky ribbon lowered into the gutter used for manure removal by flushing were more satisfactory sampling methods than using counts of flies caught on sticky ribbons carried along the aisles or aspirator collections from the gutters. For the visual count method, the effects of location in the house, within each aisle, and feed trough height were determined; two counts on feed troughs in each of two inside rows of cages were sufficient to measure population changes. For routine monitoring of D. repleta populations, visual counts of flies resting on the feed troughs in the front area of two aisles and catching flies on sticky ribbons inserted into the rear gutter area are recommended. [ABSTRACT FROM AUTHOR] |
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