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Breakthrough Made in Sea Lice Resistance

23 June 2016

UK - A breakthrough has been made in fighting sea lice resistance with a new sea lice treatment programme from Benchmark Animal Health. The programme has been proven in trials to kill all stages of lice, including those resistant to azamethiphos - a frequently used sea lice medication.

 ‘Salmosan® Vet All-in-One’ (patent pending) is a treatment programme using the synergy between low salinity water (around 1-3ppt) and Salmosan® Vet to achieve maximum efficacy against sea lice whilst also improving fish welfare by minimising stress.

Fish are usually treated in salt water but this treatment programme in low salinity water allows the farmer to treat all stages of multi-resistant sea lice effectively. Field trials have demonstrated treatment efficacy up to 100 per cent, including lice populations previously showing resistance to azamethiphos.

In order to treat the fish, the optimum regime is a bath treatment consisting of 3 hours in low salinity water, with Salmosan® Vet added for the final 60 minutes.

It is important to note that the 3-hour treatment time is adhered to as shorter treatment times will result in reduced efficacy and are likely to contribute to the development of resistance to both freshwater treatment and azamethiphos.

The programme also 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.

When used as part of a strategic treatment plan, Salmosan® Vet All-in-One programme is a significant next step for the effective control of sea lice.

Benchmark Animal Health recommends and encourages all producers to discuss the programme with them before deploying it on their farms.

Salmosan® Vet must always be used at the label indicated dose, i.e. 0.2mg Salmosan® Vet per litre water for 60 minutes. Lower doses or lower time exposure are likely to result in reduced efficacy and contribute to the development of resistant sea lice populations. For more information on the programme please contact:

Rune Stigum Olsen (Norway & Faroe Islands): [+47 481 88 648]
Bernhard Laxdal (Norway & Faroe Islands): [+47 452 25 761]
Robert Reilly (UK/Scotland): [+44 (0)7721 219 385]

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