BIOCHEMICAL OXYGEN DEMAND(BOD) is one important indicator of how much oxygen is needed to stabilize organic wastes. The BOD of many industrial and municipal wastes is known, and ranges of experimental values for wastes voided by most commercial animals have been published (Loehr, 1968). Such data are used in the design of waste treatments and as pollution-control criteria. The BOD that fed fish impose on their environmenis, however, has not been investigated previously.We needed to know the BOD of wastes from fed channel catfish (Ictalurus punctatus) so we could evaluate experimental waste treatments for fish reared at high population densities in a closed, recirculating water system. The information also is needed in estimating the pollution potential of new techniques of intensive catfish culture in sluices, raceways, and sireams.Therefore, we designed a system to measure the BOD of wastes from two adult channel catfish.
ContributionNo. 191, Department of Agricultural Engineering, Kansas Agricultural Experiment Station, Manhattan, Kansas 66502. THE PROGRESSIVE FISH-CULTURIST 195
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