Received: 18-02-2013 / Accepted: 15-06-2013
Formulated feed for rainbow trout at the beginning of growing phase from10g/fishto120g/fishwas conducted incoldwateraquaculture researchcenterin Sapa-Lao Cai. The experiment wasarrangedwithfivedifferentfeedincludingan imported feed from Finland andfourlocal formulated feed(TACB1, TACB2, TACB3, TACB4) containing46% proteinand18% lipid. Fishmealincorporationleveldecreased from62.27% to 52.75% andtheincorporationlevelofplant ingredientsincreases from14.66% to 38.4% in four local formulated feed. After75 daysofexperiment,resultsshowedthatthe growth performanceofrainbow troutarerelativelyhighintheexperimentalfeeds(from 1.43 to 1.47 g/fish/day), survivalrate high(98.0% -99.3%), lowfeedconversionratio(1.41 to 1.44). Therelative gutlength of fish wasproportional to theincorporationlevelofplant ingredients in experimental feed. The growth rate, feedconversionratioand survival rateof fish fed TACB3using56.12% fishmealand25.72% plant ingredientwere similar to fish fedFinlandfeed. The use of TACB3 can be reduce the production cost of 18% in comparison to imported feed, thus TACB3 can beusedasformulatedfeedforrainbowtrout at the beginning of growing phase.