By a News Reporter-Staff News Editor at Life Science Weekly -- Investigators publish new report on Life Science Research. According to news reporting from Trondheim, Norway, by NewsRx journalists, research stated, "Particle accumulation in recirculating aquaculture systems (RAS) are generated from uneaten food and feces, and bacteria tends to proliferate. Small organic particles act as substrate for bacterial growth and may by direct interference with gills cause stress and reduce disease resistance for the cultivated species."
The news correspondents obtained a quote from the research from the Norwegian University of Science and Technology (NTNU), "Most diseases in aquaculture of marine fish larvae are caused by opportunistic microorganisms that become pathogenic when the fish is under stressed conditions. The present study investigated the potential of using a membrane bioreactor (MBR) as a part of the water treatment in a RAS for production of marine fish larvae, since the small pore size (50 nm) efficiently removes organic particles including the colloidal fraction in the system. The experiment was a 50 day start-feeding experiment with Atlantic cod (Gadus morhua L.), comparing water quality and larval performance in a conventional RAS (cRAS) with a membrane filtrated RAS (mRAS). In mRAS, 8.5% of the water flow was at any time membrane filtrated. The present study showed that the MBR improved water quality significantly by reducing turbidity and by lowering the total number of bacteria in the rearing water (up to 80% reduction). Microbial communities in water samples were significantly different between cRAS and mRAS already on 5 days post-hatching (dph) and throughout the experiment. The microbial community composition of the rearing water was significantly different from the composition of the larval microbiota during the experiment, although differences between larval samples were different only on 50 dph. The present study showed the potential of using MBR to lower the bacterial carrying capacity (CC) by efficiently removing organic particles and bacteria."
According to the news reporters, the research concluded: "In average a 13% higher cod larval growth (weight, %) at 40 dph and a 3.0% higher survival rate at 50 dph were measured in the mRAS scheme."
For more information on this research see: Effects of membrane filtration on bacterial number and microbial diversity in marine recirculating aquaculture system (RAS) for Atlantic cod (Gadus morhua L.) production. Aquaculture, 2014;422():69-77. Aquaculture can be contacted at: Elsevier Science Bv, PO Box 211, 1000 Ae Amsterdam, Netherlands. (Elsevier - www.elsevier.com; Aquaculture - www.elsevier.com/wps/product/cws_home/503302)
Our news journalists report that additional information may be obtained by contacting P.A. Wold, Norwegian University Science & Technology, Dept. of Biotechnol, N-7491 Trondheim, Norway. Additional authors for this research include A.B. Holan, G. Oie, K. Attramadal, I. Bakke, O. Vadstein and T.O. Leiknes (see also Life Science Research).
Keywords for this news article include: Norway, Europe, Trondheim, Life Science Research
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