By 1J. O. Evjemo, 2K. I. Reitan and 1Y. Olsen - UGent JO.pdf · Artemia sp. and T. longicornis Time...

Hopp til første side

Copepods as live food organisms for marine fish larvae

By 1J. O. Evjemo, 2K. I. Reitan and 1Y. Olsen

1 Trondhjem Biological station,Norwegian University of Science and Technology (NTNU),Trondheim, Norway

2 SINTEF, Fisheries and Aquaculture, 7465 Trondheim, Norway


First feeding of marine fish larvae using copepods

Stolt Sea Farm AS,RubbestadnesetBømlo, Norway


Semi-intensive production of cod (Gadus morhua L.)and halibut (Hippoglossus hippoglossus L.) larvae

Meøypollen in Lofoten, Norway

Lofilab AS,Lofoten, Norway


Wide range of zooplankton species, size and developmental stages

■ Early spring dominated by nauplii and copopodidstages

■ Late spring and summer - higher numbers of adult stages

■ Chemical composition is variable

Photo: Tora Bardal, NTNU


Total lipid content in Temora longicornis and Calanus finmarchicus from late April until

late June – early July (data from different years)

0

10

20

To

tal

lip

id c

on

ten

t (%

of

DW

)

0

10

20

30T. longicornis

C. finmarchicus

April May June July

Total lipid contentTotal lipid content

Total lipid content

Total lipid contentTotal lipid content

Photo: Tora Bardal, NTNU


Absolute and relative content of DHA in T. longicornis, C. finmarchicus and Eurytemora sp.

DH

A c

on

ten

t (m

g g

-1 D

W)

0

10

20

30

% D

HA

of

tota

l fat

ty a

cid

s

0

10

20

30

40

T. longicornis C. finmarchicus

AprilMay June

AprilMay June

July

Eurytemora sp.

June5/6 11/6

Major fatty acid in the copepods:

DHA, EPA,16:0


Absolute and relative content of EPA in T. longicornis, C. finmarchicus and Eurytemora sp.

EP

A c

on

ten

t (m

g g

-1 D

W)

0

10

20

% o

f to

tal

fatt

y ac

ids

0

10

20

30

T. longicornis C. finmarchicus

April

May JuneApril

May JuneJuly

Eurytemora sp.

June5/6 11/6


% o

f tot

al fa

tty

acid

s

0

20

40

60

80

100

0

50

100

150

200

250

300

mg

g-1 D

W

A. franciscana C. finmarchicus Acartia sp.Eurytemora sp.T. longicornis

22:6n-3 (DHA)22:5n-320:5n-3 (EPA)other n-3sum n-6mono unsaturatedsaturated fatty acidslipids that are not fatty acid

nauplii (newly hatched) and after Artemia franciscanaenrichment with two enrichment diets

Common copepods from northern coastal waters

Fatty acid profiles of different live food organisms


Protein content in different live food organisms

A. franciscans nauplii (newly hatched) and after enrichment

Common copepods from northern coastal waters

Prot

ein

cont

ent (

% o

f DW

)

0

20

40

60

80

100

A. franciscanaC. finmarchicus Acartia sp.

Eurytemora sp.T. longicornis


DHA content in cultivated and wild live food organisms during starving conditions

Time (hours)

0 20 40 60 80 100 120

% D

HA

(o

f to

tal f

atty

aci

ds)

10

20

30

40

50

60A. fransiscana (12°C) T. longicornis (12°C)B. plicatilis (18°C) Eurytemora sp. (10°C)


Lossrate of total lipid content, EPA and DHA during starving conditions in various live food organisms

Loss rate expressed as % reduction day-1 of different lipid components in T. longicornis, Eurytemora sp. and

A. franciscana during starvation at 12.5°C ± 1

Total lipid content 18 12 11EPA 26 17 15DHA 14 10 51

T. longicornis Eurytemora sp. A. franciscana

Loss rate (% day-1)

SLR = ln(Qt / Q0)/t

%LR = (eSLR - 1) ⋅ 100


Why are copepods superior to enriched Artemia sp. in first feeding of halibut larvae?

DHA content in halibut larvae (H. hippoglossus) fed Artemia sp. and T. longicornis

Time (days)

0 10 20 30 40

DH

A c

on

ten

t in

hal

ibu

t la

rvae

(%

of

tota

l fat

ty a

cid

s)

0

10

20

30

40

50larvae fed T. longicornis larvae fed enriched Artemia sp.larvae fed juvenile Artemia sp.

DHA content in live food organisms:T. longicornis 38% of tot. FAEnriched Artemia sp. 15% of tot. FAJuvenile Artemia sp. 16% of tot. FA

Photo: Institute of Marine Research, Bergen


Relationship between the DHA content (% of total fatty acids) in different live food organisms and in halibut

larvae (H. hippoglossus)

% DHA in live food organism

0 10 20 30 40

% D

HA

in h

alib

ut

larv

ae

0

10

20

30

40

50% DHA in larvae = 0.98(% DHA in live food organism) + 0.55r2 = 0.95

Photo: Institute of Marine Research, Bergen


Lessons learned after 10 years use of marine copepods in Norwegian marine larvaeculture

■ Nutritional quality of copepods are considered as optimal◆ Lipid and fatty acid content

◆ Protein content

◆ vitamins and minerals

■ Availability (restricted to 4 months)◆ density and species composition are highly variable

■ Production number of fish fry (200 000 - 800 000 year -1)

■ To obtain profitable whole year production of fish fry intensively produced live food organisms must be recommended


Intensive production of live food organisms

■ Copepods might be used as a supplement during certain periods of the year

■ Production of Artemia sp. and rotifers must be given high priority

■ Develop new enrichment diets for marine cold water fish species

◆ establish a main reference from copepod analysis and further develop intensive live food production (Artemia sp. and B. plicatilis)


ConclusionsT. longicornis, Acartia sp. and Eurytemora sp. had a total lipid content close to 10%

HUFA level ranging from 55% to 62% of total lipid content

The dominant fatty acids were DHA (25.5 - 42%), EPA (15.1 - 24%) and 16:0 (8.4 – 12%)

In variuos stages of C. finmarchicus the dominant fatty acids were DHA (17 - 31%), EPA (17 - 23%) and 16:0 (9 - 16%)

During early spring the lipid content increased more than 50% and adult stages had a total lipid content close to 25% of DW

Size and species composition can be highly variable


Conclusions

In the copepods the protein content varied between 52.4 and 57.6% of DW, and is significantly higher than in A. franciscana (p< 0.005)

There is a close relationship between the percent DHA content in the halibut larvae and in different live food organisms fed to the larvae. High DHA content in the live food organism was reflected by a high DHA content in the larvae and vice versa

There are significant differences in the lipid content and the distribution of fatty acids in the marine copepods examined and enriched A. franciscana. The copepods are characterised by a relatively low lipid content and a high n-3 HUFA content.

Through proper enrichment diets the nutritional value of cultivated live food organisms will reach the requirements of the larvae


Further perspectives

■ Ongoing research programme ”Calanus” (2001 - 2005)

■ Harvesting and use of zooplankton as a bio-resource for fish feed and industrial raw material

◆ Copepod - oil for Artemia sp. and rotifer enrichment

■ In the Norwegian Sea it is estimated 200 mill ton of Euphausids, C. finmarchicus and Amphipods. If 0.5% of the biomass is harvested (1 mill ton) this is the same amount of biomass used for fish meal and oil in Norway today

By 1J. O. Evjemo, 2K. I. Reitan and 1Y. Olsen - UGent JO.pdf · Artemia sp. and T. longicornis Time...

Documents

Transcript of By 1J. O. Evjemo, 2K. I. Reitan and 1Y. Olsen - UGent JO.pdf · Artemia sp. and T. longicornis Time...