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1	Evaluation of automated, manual and constant aeration practices in managing of dissolved oxygen for channel catfish farming in earthen ponds Fortune, Shelby E 09 August 2008 (has links) Maintaining dissolved oxygen concentrations under different operating schemes (constant, manual or automated aeration control) was evaluated in 20 earthen catfish ponds ranging from 0.04 to 0.07 hectares in size. Ponds were assigned to treatments based on achieving equal distribution of biomass among treatments. Catfish weighing approximately 0.11 kg each were stocked at a rate of 14,820 catfish/hectare and were fed, to satiation, a 36% crude protein floating feed for the first week and switched to a 32% crude protein floating feed for the remainder of the study. Percentage weight gain, FCR and survival were calculated but did not differ among treatments. A partial enterprise budget analysis was generated to determine comparative value of different aeration techniques relative to production costs. Mean partial net returns did not differ among treatments. Complete comparison was not possible due to failure of automated monitors to record DO and to operate aerators under designed protocols. diurnal oxygen profile catfish catfish production percentage weight gain FCR percent survival net production partial enterprise budget oxygen monitoring aeration dissolved oxygen water quality constant aeration catfish sales partial net returns automated oxygen monitors