Change search
ReferencesLink to record
Permanent link

Direct link
Effects of different water treatments on microbial communities when startfeeding European lobster (Homarus gammarus)
Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, Department of Biology.
2014 (English)MasteroppgaveStudent thesis
Abstract [en]

The challenge with poorly performing larvae and high mortality in replicate tanks is a bottleneck in aquaculture. The main objective of this thesis has been to reveal if differences in performance and survival of the reared larvae is caused by instability in the microbial communities in the rearing water, and furthermore to investigate if disinfection devices also contribute to this instability and work against its purpose, which is to increase the level of performance and survival. The European lobster (Homarus gammarus) was used in the experiment because this species is subject to a lot of research today. Two recycling aquaculture systems (RAS), of which one included an ultraviolet filter (UV filter) and one flow-through system (FTS) with no UV filter were compared. The samples were analysed using a PCR (Polymerase chain reaction) and DGGE (Denaturing gradient gel electrophoresis) strategy and tested statistically for variations between the systems. Samples were taken from intake water, rearing water and from whole larvae. There were indications that the water treatment influenced the microbial communities in both water and larvae of the systems. RAS with no UV filter presented the highest rate of survival and showed the most similar microbiota between intake water and rearing water. The RAS with UV filter and FTS both showed significant differences between intake water and rearing water, creating a room for regrowth for bacteria. This study support the hypothesis that r-strategic bacteria will be favoured in unstable systems and create opportunity for pathogens to dominate the waters, resulting in less optimal conditions for the reared organism. It also supports the theory that using disinfection on the water before entering the rearing systems will lower the total bacteria concentration and may create instability and room for re-growth. The experiment was executed at the Norwegian Unicersity of Science and Technology (NTNU) with participation from, Sintef fisheries and aquaculture and Norsk hummer AS. Live-feed experiment was performed at NTNU Brattøra and the laboratory work was done at NTNU Gløshaugen. The live-feed was produced by Sintef Fisheries and Aquaculture, and the lobster larvae were produced at Norsk Hummer AS, Tjeldbergodden.

Place, publisher, year, edition, pages
Institutt for bioteknologi , 2014. , 55 p.
URN: urn:nbn:no:ntnu:diva-27003Local ID: ntnudaim:8771OAI: diva2:755540
Available from: 2014-10-14 Created: 2014-10-14 Last updated: 2014-10-14Bibliographically approved

Open Access in DiVA

fulltext(3568 kB)494 downloads
File information
File name FULLTEXT01.pdfFile size 3568 kBChecksum SHA-512
Type fulltextMimetype application/pdf
cover(652 kB)11 downloads
File information
File name COVER01.pdfFile size 652 kBChecksum SHA-512
Type coverMimetype application/pdf

By organisation
Department of Biology

Search outside of DiVA

GoogleGoogle Scholar
Total: 494 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 35 hits
ReferencesLink to record
Permanent link

Direct link