Benchmark claims sea lice breakthrough

BENCHMARK Animal Health has developed a new treatment to combat sea lice that it claims has achieved 100 per cent success in field trials.
‘Salmosan Vet All-in-One’ is a treatment utilising the synergy between low salinity water and Salmosan Vet to achieve maximum efficacy against sea lice and improve fish welfare by minimising stress.
A low level of salinity is achieved when salmon held in the marine environment are introduced into freshwater treatment units such as well boats.
The Salmosan Vet All in One programme can be used to treat all stages of multi-resistant sea lice, with field trials demonstrating treatment efficacy up to 100 per cent.
Work to date has demonstrated the optimum regime is a bath treatment consisting of three hours in low salinity water, with Salmosan Vet added for the final 60 minutes (total treatment time being three hours).
Benchmark says it is important for producers to adhere to this three-hour treatment time as shorter periods will result in reduced efficacy and are likely to contribute to the development of resistance to both freshwater and azamethiphos.
Shorter treatment times have shown some effect on some stages of sea lice in laboratory trials. However, these results have not been reproduced under commercial field conditions and are unlikely to kill juvenile stages of sea lice.
Tank trials and subsequent commercial treatments using the three-hour Salmosan Vet All-in-One program have killed all stages of lice, said Benchmark.
Lice populations previously showing resistance to azamethiphos were successfully treated with up to 100 per cent clearance using this programme.
Salmosan Vet All-in-One substantially reduces the time the fish need to spend in a low salinity water treatment, therefore reducing stress on the fish and allowing more efficient use of treatment facilities.
Benchmark say that Salmosan Vet must always be used at the label indicated dose – 0.2mg Salmosan Vet per litre water for 60 minutes.
‘We have achieved some extremely positive results with this programme and our technical support team has gained some valuable experience regarding water quality parameters (e.g. oxygen, carbon dioxide and ammonia),’ the firm said today.
‘It is vital that these are managed properly and extra vigilance is needed when holding fish for extended treatment periods.
‘We would encourage all producers to discuss this with us before deploying it on their farms.’