The bright side of lice

by Rob Fletcher, editor rob@fishfarmingexpert.com

Reading about the latest research into sea lice genetics, as presented in François Besnier’s excellent article on page 26, makes for chilling but instructive reading. The frightening element is the fact that resistance to Emamectin benzoate across the whole of the North Atlantic appears to have spread from the progeny of a single louse. That the genetic mutations of an individual organism could so effectively undermine the efficacy of SLICE treatments on the salmon farming industries of Norway, Scotland, Ireland, the Faroes, Iceland and Canada is quite remarkable. And that the resistance could spread so rapidly across such a huge area is even more impressive, chronically decreasing the efficacy of the drug within a decade of its launch. This example illustrates one of the many challenges facing the industry, helps to explain why all therapeutants are likely to have a limited shelf life and reflects why the sector’s struggle against copepods is likely to go the distance. Yet there is also perhaps another – more positive – lesson to be learned. Indeed, the industry should perhaps seek to emulate the single trailblazing louse that helped to save its species from the scourge of Emamectin. Not by adopting its exceptionally brief lifecycle – one of the reasons the resistance to the treatment was able to spread so quickly – but by ensuring that ideas and initiatives that succeed in one part of the salmon farming world take root quickly and can be rapidly passed on to operators in other countries. Although there is clearly a healthy element of competition between salmon farming operators, and there are some trade secrets that need not be shared, passing on any information that helps to improve fish health and containment, in particular, will benefit the industry as a whole – both in terms of salmon welfare and the reputation of the sector. A similar theme – the need to promote a more symbiotic relationship between industry and academia – was very much evident at the recent PhD research conference at Stirling’s renowned Institute of Aquaculture in February. As well as providing a welcome opportunity to meet some of the brightest research prospects in the sector and to find out more about the sort of projects that help to underpin the industry’s long term development, it was encouraging to see that the sponsors of the event included some of the best know aquaculture companies in the UK – a move that shows the high regard with which the industry views such ventures. This dissemination of information is also, I hope, something that Fish Farming Expert magazine and our sister website www.fishfarmingexpert.com can help with. Having started full time with the company in January I have been impressed by the pool of journalists, researchers and industry figures we can call on for updates and analysis from across the salmon producing world and I hope that we can help keep you up to date as new developments occur and old enemies evolve.