Nanofiltration of intake water in RAS: Effect on fish performance, health and welfare
Abstract
The experiment tested the effect of nanomembrane filtration in RAS on the salmon's physiology, welfare and
growth. A specially designed membrane was used to remove sulphate from seawater and to adjust salinity from
32 to 12 ‰. A RAS where salinity was adjusted to 12 ‰ by mixing raw seawater and freshwater was used as
control. The fish were kept in the two systems for 10 weeks before being transferred to tanks with seawater flow
through for 4 weeks. Histology and measurements of gene expression in the gills, intestine, and skin were done
and blood samples were taken to measure the content of cortisol and blood plasma ions after transfer to seawater.
Post smolt in RAS with nanofiltered water grew slightly better compared to traditional RAS and the same tendency
was maintained after transfer to seawater. There were no differences between systems in welfare indicators or
skin morphology. In RAS with nanofiltration, some individuals showed an increase in the area of the gill lamella
covered by mucus-producing cells and a lower number of chloride cells on the secondary lamellae in the gills.
The effect of nanofiltration on gene expression in skin and gills was small, with only two genes that were
differentially expressed in skin and 28 genes in gills
Description
Source at https://nofima.no/.
Publisher
NofimaSeries
Nofima rapportserie ; 19/2022Citation
Ytrestøyl TY, Sveen L, Krasnov A, Dalum AS, Kolarevic J. Nanofiltration of intake water in RAS: Effect on fish performance, health and welfare. Nofima AS; 2022. 18 p.. Nofima rapportserie(19/2022)Metadata
Show full item recordCollections
Copyright 2022 The Author(s)