Danish farmer invests in new on-board stunner

Ace Aquatec
November 5, 2021

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Danish trout producer Musholm was the first fish farmer to install an Ace Aquatec humane stunner on board a boat. That was in 2016 and after marked improvements in efficiency, product quality and animal welfare, the company decided to buy another machine.

The new stunner, installed on a second harvesting boat in September, was acquired as a back-up to the first machine, which has been upgraded recently with new electrodes.

The in-water stunning technology has proven to be ideal for Musholm’s high throughputs, with fish extracted directly from the sea cages and rendered unconscious in seconds, ready for bleeding, which is also carried out on board.

The pipeline system, which runs from the boat’s generator, minimises handling, and the fact that fish are stunned in water prior to slaughter reduces stress which, in turn, results in better quality flesh.

Farm manager Anders Lejbach said before switching to the Ace stunner, they had used CO2 diluted in water to stun their fish.

‘It was an old-fashioned slaughterhouse with some of the fish still lively and some dying before we started to bleed them. Now it’s much more efficient and much faster.’

Musholm, a vertically integrated firm which has been rearing rainbow trout on Denmark’s Great Belt since 1979, produces around 4,000 tonnes a year, for European and Asian markets.

The company embarked on its initial trial with Ace Aquatec after seeing a prototype of the humane stunner on Fresh Corporation’s yellowtail kingfish farm in Volklingen in Germany.

Lejbach was quickly convinced of the award-winning system’s merits by Ace Aquatec CEO Nathan Pyne-Carter but he wanted to be sure he understood the technology.

‘Because we were the first to fit it to a harvesting boat, I wanted to see if I could install it myself so I took it off and then put the whole system back board on again. But we’re just fish farmers and don’t want to do too much with the electronics, so it means a lot to us that the stunner is easy to work with and user-friendly.’

Lejbach said productivity had increased by 20 to 25 per cent, principally in manpower savings, as fish were being stunned and bled more efficiently.

‘The staff are very happy with the machine and can never go back to the old system,’ he said.

‘What has changed the most for us is that we now bleed the fish better, which also affects the quality of the roe we sell. We have much more Grade A roe,’ said Lejbach.

Musholm secured ASC certification in 2016, an achievement made possible by the more humane slaughter process. ‘For ASC certification we are not allowed to use CO2 to stun the fish. We can also point to the fact that Ace’s stunning technology has won prizes for fish welfare.’

Musholm has also bought a stunner for one for its sister companies in Japan, which is now enjoying the benefits of the technology. 

Lejbach said that as one of the first to use the stunner, he has no hesitation in recommending Ace Aquatec to other farmers. ‘I have done so maybe 10 to 12 times, I’m one of your best sales guys! I talk to people all around the world about this stunner, because everybody wants to talk to somebody who has used it. They know I am not going to tell them what they want to hear. I am just going to tell the truth.’


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