Lumpfish, known scientifically as Cyclopterus lumpus are found in the waters of the Artic and Atlantic oceans.
They have distinct features, including a round body, short fins and can be found growing up to 60cm in length.
The species are vital to tackling the problem of sea lice in salmon, especially within fish farms.
Lumpfish Image credit: Government of Canada
Experts at the University of Stirling’s Institute of Aquaculture, alongside the research institute Fiskaaling in the Faroe Islands have produced new research that could help improve the welfare of farmed lumpfish.
The study was funded by Fiskaaling, HiddenFjord, the Fisheries Society of the British Isles, and the Scottish Aquaculture Innovation Centre.
The research has found that liver colour is an important indicator of general welfare in lumpfish. The species are increasingly being used by the salmon industry to remove parasites more naturally and effectively.
Nature Scientific Reports have published research that has identified correlations between liver colour, the nutritional welfare and health status of the species, as well as other commonly used indices including fin damage and skin lesions.
The team sampled lumpfish for welfare indicators, liver colour and stomach contents, and collected lumpfish liver samples, at a number of sea farms.
The Institute of Aquaculture carried out posterior nutritional and histopathological analysis of the samples.
Dr Sonia Rey Planellas, led the University of Stirling’s contribution to the study.
She said: “Our study found that lumpfish are predominantly generalists and opportunistic feeders when in cages – and this is impacting on their health and welfare.
“We were able to identify different liver colours that correlate with their health and welfare status. This technique could be used by the industry to identify any issues, and to modify husbandry and feeding – such as supplementing lumpfish feeds with essential nutrients and pigments, as necessary.
“Ultimately, this study will help to improve the development of the fish in hatcheries and when they are deployed in sea farms with the salmon – which is important because their welfare must be maintained to enable them to remain efficient and eat the sea lice from salmon.”
Dr Sonia Rey Planellas Image credit: University of Stirling
The project was also conducted by many specialists in the Faroe Islands, in collaboration with Dr Kirstin Eliasen of Fiskaaling, and Esbern Patursson of the salmon farming company Hiddenfjord.
A Stirling student who is pursuing a masters, Enrique Pino Martinez, and Institute of Aquaculture staff Dr Monica Betancor, Dr Johanna Baily, Dr Bruce McAdam, and Dr Bernat Morro Cortes also provided support.
The study can be found here https://www.nature.com/articles/s41598-020-65535-7
Feature image credit: Benchmark plc