Centre for Closed-Containment Aquaculture

Health and performance of Atlantic salmon post-smolts when using novel production protocols

Trine Ytrestøyl

Objective:

The industry is already using practices when producing large fish for

stocking, that have not been evaluated scientifically, in terms of

effects on fish performance, health and welfare

Objective: To evaluate the effect of different postsmolt production

protocols in RAS on fish performance, health and welfare in the seawater

growout phase

«Best in RAS =best in the sea?»

Hypothesis: An extended land-based phase in RAS will improve fish

performance in sea cages

Experimental design :

2x2 factorial design with salinity and light treatments as factors,

and transfer to seawater pens at 200 and 600 g

Control group «traditional» 100 g smolt, 12:12 L:D, 6 weeks

30 40 50 60 70 80 90 100 150 200 250 300 350 400 450 500 550 600 1000 2000 3000 4000 5000

Control FT FW-RAS 24:00 Stocking at sea

Treatment A1 FT FW-RAS 24:0024:00 Stocking at sea

Treatment A2 FT FW-RAS 24:0024:00 Stocking at sea

Treatment B1 FT FW-RAS 24:0024:00 Stocking at sea

Treatment B2 FT FW-RAS 24:0024:00 Stocking at sea

Treatment C1 FT FW-RAS 24:00 Stocking at sea

Treatment C2 FT FW-RAS 24:00 Stocking at sea

Treatment D1 FT FW-RAS 24:00 BR-RAS, 24:00 Stocking at sea

Treatment D2 FT FW-RAS 24:00 BR-RAS, 24:00 Stocking at sea

FW-RAS 24:00

12:12+Vacc, 6 wk FW-RAS 24:00, 6 wk

Vacc

Vacc

12:12+Vacc, 6 wk

12:12+Vacc, 6 wk

Vacc

Vacc

FW-RAS 24:00, 6 wk

FW-RAS 24:00

FW-RAS 24:00

FW-RAS 24:00

12:12+Vacc, 6 wk

12:12+Vacc, 6 wk

Treatments Fish size (g)

BR-RAS 24:00

BR-RAS, 24:00

FW-RAS 24:00, 6 wk

12 ppt SW

12:12 FW x 12:12 12 ppt x 12:12

24:00 FW x 24:0 12 ppt x 24:0

LightSalinity

Samplings 2017: May Sept Nov

Control,12:12 LD, FW

12:12 LD, 12 ppt, 200g

12:12 LD, 12 ppt, 600g

24h, FW, 200g

24h, FW,600g

12:12 LD, FW, 200g

12:12 LD, FW, 600g

24h,12 ppt, 200g

24h,12 ppt, 600g

200 g

600 g

• SGR/TGC

• Survival

• Maturation

• Welfare

• Cataract

• deformities

• Pigmentation

• Slaughter quality

• Vaccine sideeffects

1st period in the sea

5 weeks after transferSW

Challenge

72 h

34 ppt

Response variables

Feed intake

Survival

FCR and growth

11x11 m

cages

(4+ kg)

11x11 m

cages

(4+kg)

• SGR/TGC

• Survival

• Maturation

• Seawater tolerance

• Welfare

• Cataract

• Skin health

• Deformities

• Pigmentation

• Vaccine sideeffekts

• Immunocompetence

100 g

(5x5x5 m cages)

Gildeskål Research Station

(GIFAS)RAS Sunndalsøra

RAS conditions

• 3.3 m3 tanks, 300 fish per tank, PIT-tagged

• Temperature: 12-13 oC

• Recirculation: >99%, ~20% exchange/day

• No ozone

• O2 >85% saturation (tanks controlled independently)

• pH > 7.5,

• CO2 < 10 mg/L

• TAN < 1.0 mg/L

• Nitrite < 0.2 mg/L

• Water velocity: ~1 BL/sec

• Max. density 50 kg/m3

• Commercial diets

Performance in RAS:

214 208

282 263

543 557605

574

0

100

200

300

400

500

600

700

12 ppt FW 12 ppt FW

12:12 12:12 24 h 24 h

Bodyweigth at seawater transfer 200 g

600 g

0

100

200

300

400

500

600

700

6/1/2016 7/1/2016 8/1/2016 9/1/2016 10/1/2016 11/1/2016 12/1/2016

(g) 12:12 FW 12:12 12 ppt 24 h FW 24 h 12 ppt

transfer 200g

transfer 600g

transfer 100gstart 12:12 LD

• 24:0 improved growth in RAS• 12 ppt improved growth in fish kept on 24:0 LD• Low mortality (>0.5 %)

Specific growth rate (SGR) and thermal growth coefficient

(TGC) in RAS:

200g: 24:0 >12:12 , 12 ppt > FW 600g: 24:0 >12:12 salinity, NS

1.71 1.691.93 1.861.97 1.93

2.452.34

0.00

0.50

1.00

1.50

2.00

2.50

3.00

12 ppt FW 12 ppt FW

12:12 12:12 24 h 24 h

Growth to transfer at 200 gSGR

TGC

1.63 1.65 1.68 1.64

2.25 2.28 2.37 2.30

0.00

0.50

1.00

1.50

2.00

2.50

3.00

12 ppt FW 12 ppt FW

12:12 12:12 24 h 24 h

Growth to transfer at 600 gSGR

TGC

200 g: 24:0 >12:12 , FW > 12 ppt 600 g: No effect of salinity or light treatment

Condition factor (CF) in RAS

Results during RAS stage: Seawater tolerance

13.713.1

13.812.6

11.9

10.49.5

10.1

11.6

10.08.7 9.2

0

2

4

6

8

10

12

14

16

18

12:12 FW 12:12 12 ppt 24 h FW 24 h 12 ppt

(µm

olA

DP/

mg

pro

tein

/h))

Gill Na+/K+ –ATPase activity 22.sep 09.nov 28.nov • NKA activity decreased during fall in all treatments

• NKA akt. were not sign. different among treatments in late September

• In late November, NKA levels were higher in fish given a winter signal

• No significant effect of salinity

(Analysed by Pharmaq Analytic)

Sea water tolerance tests (72h at 34 ppt )

0

20

40

60

80

100

120

140

160

FW 12 ppt FW 12 ppt

12:12 12:12 24:0 24:0

Serum chloride 22.sep 16.nov 05.des

• No significant effects of treatment on serum levels of Cl, Na and Mg

• No mortality

Results from the seawater phase at Gifas

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0

Temperature

Benchmark trial Average max min

100 g

600 g

200 g

Mortality first 5 weeks after transfer

3.03.4

1.3 1.3 0.6

2.72.4

1.6

2.9

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

% mortality 1st period in sea cages (5x5m) 200g

600g

• Low mortality the first 5 weeks after sea transfer• No sign. effects of treatment• Fish were in good condition at transfer, no scale loss

200 g transfer

Performance the first 5 weeks in seacages (5x5m)

Growth and feed conversion ratio (FCR)

• 200g fish: 24:0 h light during the whole production period in RAS gave lower TGC and higher FCR, no sign. effect of salinity

• 600g fish: Positive effect of 12 ppt on TGC and FCR

• Negative correlation between TGC and condition factor at sea transfer

1.98 1.942.04

1.401.31

1.66 1.59 1.631.48

0.00

0.50

1.00

1.50

2.00

2.50

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

TGC 200g

600g

0.961.09 1.06

1.291.44

1.071.18

1.011.15

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

FCR

Growth rate the 2nd period in the sea (11m cages)

3.813.39 3.32

3.09 3.113.34 3.25 3.34 3.15

0.0

1.0

2.0

3.0

4.0

5.0

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

TGC 200g (Nov-May) 600g (Jan-May)

0.730.64 0.63

0.56 0.580.53 0.52 0.52 0.50

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

SGR

945 918 896 950 9061,044 1,048

1,1391,049

0

200

400

600

800

1000

1200

1400

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

Bodyweight end of May 2017• 600 g were largest in the end of May • Highest SGR and TGC in controls, • no sign. difference in TGC between 200 and

600g• Higher SGR in 200g than in 600g• Lack of winter signal gave lower growth in

200g fish, but not in 600g fish• No sign. effect of salinity on growth rate

Growth in sea cages 3rd period in the sea (May-Sept 2017)

• control > 200 g > 600 g, • Salinity : NS, Light: NS

3.78 3.60 3.67 3.69 3.63

2.71 2.64 2.472.80

0.0

1.0

2.0

3.0

4.0

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

TGC stocking at 200 g stocking at 600 g

1.14 1.11 1.13 1.12 1.11

0.84 0.82 0.750.86

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

SGR

3,2483,034 3,048 3,178 3,103

2,594 2,562 2,574 2,694

0

500

1000

1500

2000

2500

3000

3500

4000

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

BW sept 2017

Growth 3rd period in the sea(May-Sept 2017)

• Controls were largest in late september!

• TGC and SGR: control > 200 g >> 600 g • Salinity : NS, Light: NS

3.78 3.60 3.67 3.69 3.63

2.71 2.64 2.472.80

0.0

1.0

2.0

3.0

4.0

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

TGC stocking at 200 g stocking at 600 g

1.14 1.11 1.13 1.12 1.11

0.84 0.82 0.750.86

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

SGR

3,2483,034 3,048 3,178 3,103

2,594 2,562 2,574 2,694

0

500

1000

1500

2000

2500

3000

3500

4000

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

BW sept 2017

Growth rate overall (RAS + sea cages) from June 2016 to Sept 2017 (30-3000g):

control > 200 g > 600, Salinity : NS, Light: NS

2.89 2.79 2.79 2.83 2.812.46 2.45 2.45 2.50

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

TGC from June 2016-Sept 2017

200 g 600 g

1.03 1.02 1.01 1.02 1.010.98 0.98 0.98 0.98

0.0

0.2

0.4

0.6

0.8

1.0

1.2

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

SGR Juni 2016-Sept 2017

200 g 600 g

Growth rates (TGC) of all groups during RAS and threeperiods after sea transfer (end of september 2017)

Control and ~200 g at transfer to sea

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

control

12:12 12 ppt

12:12 FW

24:0 12 ppt

24:0 FW

~600 g at transfer to sea

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.512:12 12 ppt

12:12 FW

24:0 12 ppt

24:0 FW

Kumulative mortality in seawater

4.6

6.4

2.7

4.13.7

5.9

4.14.5

4.9

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

% o

f tr

ansf

ered

to

sea

kumulative mortality by the end of 3rd period in sea cages (Sept 2017)

• Survival in the sea was between 93.6 and 97.3 % at ~3 kg in September 2017

• Highest mortality in 12:12, 12 ppt

Male maturation

GSI (Gonadosomatic index)

• No significant effect of light treatment or salinity in RAS on GSI

• Very few mature males observed during the trial, both in RAS and in the sea

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

May 2017 BW ~ 1 kg Transfer at 200g

Transfer at 600g

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

control 12 ppt FW 12 ppt FW

12:12 12:12 12:12 24 h 24 h

September 2017 BW ~ 3 kg

Conclusions so far:✓Better growth in RAS in the absence of a winter signal ( 24:0) and using 12 ppt

✓However, lack of a winter signal reduced growth after transfer to seawater

✓12 ppt in RAS had positive effects on performance after transfer to sea

✓Negative effect of high condition factor on growth after sea transfer

✓All treatments gave sufficient seawater tolerance, also in 600g fish

✓High survival in RAS and sea cages in all treatments

✓No effects of treatment on male maturation, low incidence of mature males in RAS and

seawater

✓Fish transferred at 600g grew well initially in seawater, but had a reduced growth during

summer compared to fish transferred at 100 and 200 g

Follow us on:

www.ctrlaqua.no

Funded by the Research Council of

Norway and the partners, and FHF

Photo: Nofima

Thank you for your attention

And thanks to partners in CtrlAQUAand the project group in Nofima

Britt Kristin Megård Reiten

Jelena Kolarevic

Yuriy Marchenko Bendik Fyhn Terjesen(now Cermaq)

Grete Bæverfjord

Kjellrun Hoås Gannestad