Summary: | A comparative evaluation of the effectiveness for zooplankton harvest for three local fabrics (a white poplin, 120μm; grey baft, 200μm; a nylon, 235μm) and an imported standard zooplankton net of mesh size 76μm were tested in this study. Mesh sizes and gauze constitution of the fabrics were determined with an ocular micrometer under a compound microscope. Filtration efficiency and clogging rates of the fabrics were also measured. All fabrics were effective in harvesting species of the copepods, the cladocerans and the large-sized rotifer, Asplanchna . The grey baft and the nylon net were not effective in harvesting the small-sized rotifer species like Keratella , Filinia and Trichocerca . All the fabrics effectively harvested Moina , an excellent freshwater cladoceran for fish larval-rearing. Clogging rate was found to be a function of gauze constitution, while filtration efficiency was an index of both gauze constitution and mesh size of fabrics. @ JASEM
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