| Abstract: | Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Two recirculating aquaculture systems were constructed using a sequence of five tanks each. Each system contained two plant species, duckweed ( Lemna minor ) and Chinese water chestnut ( Eleocharis dulcis ); two fish species, channel catfish ( Ictalurus punctatus ) and tilapia ( Tilapia aurea ); and a freshwater prawn ( Macrobrachium rosenbergii ). Duckweed production during the 132-day experiment reached as high as 87.2 tons/hectare/year (t/ha/yr). Water chestnut production was not successful in the restricted light situation of the lab, but in an outdoor test planting, corn production was 37.2 t/ha/yr. Four feeding trials were attempted using the following percent of fish body weight: 2.5% commercial feed; 5% wet duckweed; 15% wet duckweed; and 15% wet duckweed with 1% commercial feed. Feed to flesh conversion ratios averaged 1.97:1 for the three control tanks and 1.44:1 overall for the treatment tank. The fish-fed duckweed and commercial feed grew as well or better than those fed commercial food alone. |
