AQUATE SPMP stimulates mucosal production, improves gut health and acts to significantly reduce sea lice infections in salmon

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1 AQUATE SPMP stimulates mucosal production, improves gut health and acts to significantly reduce sea lice infections in salmon C. Wallace and J. Sweetman

2 National Lice Strategy - Scotland (formed in 1997) Tripartite Working Group (TWG) of the Scottish government formed in 1999 to cater for the salmon farming industry and wild fisheries interest groups Industry adopted voluntary Code of Good Practice (CoGP) Tailored for local conditions using Area Management Agreements (AMA) Objective Early spring and summer period to be free from lice Minimise the risk of infection to wild hosts Produce low level louse profile necessary to produce first class quality salmon for customers

3 Sea lice interaction in wild and farmed Atlantic salmon Year 1 Year 2 Nov Dec Jan Feb March April May June July Aug Sept Oct Nov Dec Jan Feb March April May June July Aug Sept Oct Nov Dec Farmed smolts moved to cages Wild salmon runs Wild smolts to sea First lice appear Lice minima required Harvesting Release from one wild fish Photo - Prof. C. Todd

4 Area Management Agreements (AMA) Agreeing monitoring protocol and frequency of monitoring Weekly monitoring Monitoring for L. salmonis chalimus, nongravid mobiles (preadult males and females + adult males), adult females ( with & without egg strips) and C. elongatus mobiles. Agreeing timing and criteria for treatments Disrupt the life cycles and minimise the lice quantities Carrying out treatments Coordinate treatment (prevent development of gravid females) Optimise treatments minimise development of resistance Additional actions Separation of year classes Filtering of harvesting waste water Site fallowing Performance review C A B

5 Sea Lice life-cycle The life cycle consists of 3 phases: Free-swimming larval stages - Nauplius I, nauplius II & copepodid. Immature attached stages - Copepodid, chalimus I, II, III & IV Motile stages - (Lepeophtheirus) Pre-adult I, Pre-adult II - Mature adults - (Caligus) Mature adults Marine Harvest Scotland - Identification of sea lice AM AF G AF PA CALIGUS AM CHALIMUS

6 Robust fish defend them selves better Prophylactic health strategies Boost Natural Defence Mechanisms Maintain balance Fish condition Balance Environment Pathogen Mucosal layer is first line of defence in maintaining balance

7 Criteria for Product Selection Safe for the consumer Affordable and cost effective Proven scientific effect (no detrimental effect of long term use on animal) Involve no additional costs or complication during feed manufacture (should not require top coating, be applied at the extruder so thermo stable) Permitted for use, non GMO, traceable and stringent quality control Be available in volume from sustainable source

8 Problem identification and resolution a continual evolving process Problem Identification Lice Resistance legislation SOP Barrier protection Mucosal INNOVATION SOLUTION DEVELOPMENT Bio-Mos SPMP SCIENCE MOA Readjustment of protocol Industrial scale trials Scientific trial set up Re-adjustment of production system & SOP Results and data analysis, Discussion review Data collection (Sampling) Mucosal properties Mucus production Gut status EMB uptake Lice deposition

9 In aquaculture 12 peer reviewed publications since Over 520 published animal trials with Bio-Mos. Bio-Mos is extracted from the yeast cell wall (Saccharomyces cerevisiae) Functional glycoprotein Proven Mucosal interaction Proven Immune interactions Gut structural improvements

10 From Science to Industrial Practice Components of Aquate SPMP have been shown to:- Improve gut morphology Improve innate immunity Suppress inflammatory response Improve mucosal secretions Lower lice numbers on salmon Boosts Ememectin levels in salmon flesh Recent work with parasitic infections in fish has highlighted the role of innate immune response in parasitic defence (Alvarez-Pellitero, 2008)

11 Salmon Akvaforsk SEM and TEM - microvilli structures Control Microvilli density 2.10 Bio-Mos Microvilli density 9.75 Control Microvilli height 1.28 Bio-Mos Microvilli height 1.55

12 GIFAS: Sea lice presence on salmon Sea lice infection scoring was assessed twice within a two-weeks period. Scoring was based on 40 fish per cage. Week 5 Week % 31.6% The total number of individual salmon infected by sea lice (irrespective to species, life stage or sex) was significantly reduced by the Bio-Mos supplementation. At week 5 (P<0.009) At week 7 (P=0.013) Control fish ± ± 4.19 Bio-Mos ± % ± %

13 Marine Harvest scope of study 1.5 million fish Site A 500,000 fish AW 1.7 kilos - 14 x 24m steel net pens. Eight pens - Diet with SPMP (5kg/MT feed) av. 0.5% bw/day Jan. Aug. Six pens - Standard diet as control Site B 406,000 fish AW 2.6 kg - 8 x 100m Polar Circle net pens. All pens - diet with SPMP (5 kg/mt feed) av. 0.5% bw/day Jan - Aug No controls due to harvest-out plan. Site C 500,000 fish AW 1.7kilos - 8 x 24m steel net pens. Four pens Diet with SPMP (5kg/MT feed) av. 0.5% bw/day Jan. Aug. Four pens - Standard diet as control SLICE treatments All the fish in sites A, B and C were given SLICE at 5 kg/ton in November 2007 at the onset of sea lice intervention and again week 8 and in July in accordance with the National Treatment Strategy. Each SLICE treatment was followed within three weeks by a topical bath treatment to facilitate the removal of residual gravid lice where appropriate.

14 Commercial Trials MH Scotland Epidermal Mucus Tyical Mucus development on Salmon fed SPMP compared to control diet Loch Sunart Site C 2008 Mucus development on Arran June / July 2007 ( pen 14 ) av wt of mucus D-2 D+10 D+22 D+33 without SPMP with SPMP av wt of mucus D-2 D+10 D+22 D+33 pen 3 pen 14 time time Increased mucous production and mucosal properties interact to Prevent the resettlement of calimus post treatment Replace mucosal protection post bath treatment Prevent skin damage and scale loss Deter secondary opportunistic infections Maintain osmo-regulatory integrity

15 EmB analysis comparison with other sites out with Loch Sunart 2008 SPMP study in Loch Sunart following pulse feeding regime ug/kg site A Site B Site C site +SPMP Control Shows double beneficial effect of feeding practice and SPMP Interrupted feeding regime for EmB day 1,3,5 & 7 agreed by Veterinary Medicines Directorate to improve appetite during medication and avoid feed wastage and exposure of Emb to the environment. Increased EmB uptake in flesh when compared to previous year with continuous feeding (approx 50% higher than 2007 level). SPMP improved EmB uptake by a further 15% against controls.

16 Chalimi responses to SPMP Loch Sunart Loch Sunart Site C - Average Chalimi levels from SPMP mfed fish v controls average chalimi ch cont ch SPMP 04/01/ /01/ /02/ /02/ /02/ /03/ /03/ /04/ /04/ /05/ /05/2008 Significant period of zero resettlement despite parallel adjacent control pens.

17 Overall mobile lice response to SPMP from week 1-40 SPMP v non-spmp fed fish average total mobile lice SPMP Control week Notably lower levels of mobile lice with time using SPMP. Post-treatment in week 26 lower re-infection of mobile stages

18 Conclusions Aquate SPMP increased the production of epidermal mucus, which curbed chalimi resettlement compared with the control diet. Aquate SPMP improved gut integrity which appears to be responsible for improved SLICE uptake in fish flesh increasing treatment efficiency and lessening the effects of Emamectin on the environment A pulse feeding regime was successfully employed to improve fish feeding and SLICE uptake compared to 2007 Marine Harvest have adopted these methods as best practise and are currently feeding 10 million fish on this regime. We are developing regional strategies for lice treatments in Chile, Canada and Norway using best practice.