Norway.- The CtrlAQUA annual report for 2019 is now released, presenting an update on the latest development in research and innovation within closed containment aquaculture.
“What stands out in 2019, is that we implemented three new focus areas in our research plan. These areas are challenges that have evolved during the last years to be highly important for the industry to solve”, says Åsa Espmark, Centre Director of CtrlAQUA.
The three focus areas are the gas hydrogen sulphide (H2S), the disease nephrocalcinosis, and early sexual maturation. Not least, the annual report contains a sum up of the year, scientific highlights and more.
The deadly gas H2S
Hydrogen sulfide gas is a colorless and toxic gas that occurs in biofilm or sediment in water and has been suspected to be the cause for occasions with mass mortalities among farmed fish. The dangers that this gas poses are difficult to detect in advance, and it has become a significant problem in seawaterbased recirculating aquaculture systems in recent years.
The key to understanding the dynamics behind H2S formation is to understand the chemical reactions that occur in biofilm and sediment. In CtrlAQUA they will investigate how much sedimentation has to take place before H2S is formed and identify risk factors in order to prevent H2S formation.
Risk factors for kidney stones
Nephrocalcinosis, or kidney stones as it is also called, is a chronic kidney disease that is a growing problem in salmon farming. Kidney stones in salmon can cause difficulties in regulating salt balance and transition to seawater, reduced growth and feed utilization, and increased mortality rates. It is reported
as being a problem in post-smolt, large smolt and in salmon that are kept in land-based tanks for long periods of time. The fact that salmon are kept in land-based tanks for long periods of time has several positive effects, including on health, welfare, growth and the environment, and it makes the problem of kidney stones all the more important for the industry to solve.
“The aim is to find kidney stone risk factors in salmon that can explain the increase in the number of reported cases”, says Nofima’s Lill-Heidi Johansen, who leads the fish health research at CtrlAQUA.
How to hinder early puberty
Early sexual maturation in farmed fish is a known welfare and financial problem that has increased in high intensity production of large smolt and post-smolt in RAS, particularly when temperature and growth is high.
Generally speaking, the process of sexual maturation in males may start already when salmon reach 50 grams. When they reach the 4 to 500 gram phase, the process is increasing in intensity”, says associate professor Tom Ole Nilsen at the University of Bergen and head of the production and welfare department at CtrlAQUA.
“Can the light be used differently as a preventive measure? Are there any temperature intervals we should avoid? We think it’s a combination of several factors, but we don’t know what triggers it all”, says Nilsen. The aim is to clarify how factors such as light, temperature and fish size can affect early puberty in post-smolt.
Please view this reader friendly version of the annual report and enjoy reading!
Printable version: CtrlAQUA Annual Report 2019_Print
About CtrlAQUA
CtrlAQUA is a centre for research-driven innovation (SFI), which shall develop technological and biological innovations that will make closed-containment aquaculture systems a reliable and economically viable technology in aquaculture. The Norwegian institute Nofima is the host institution, and there are six research partners from Norway, Sweden and the United States, as well as 13 industry partners. CtrlAQUA is co-financed by the Research Council of Norway and its partners, and shall operate from 2015 to 2023.
Contact persons
Åsa Maria O. Espmark
Senior Scientist
Phone: +47 991 60 039
asa.espmark@nofima.no
Kasper Thøring Juul-Dam
Adm. Coordinator
Phone:
kasper.juul-dam@nofima.no
