Breeding of Aquaculture Species – Jade Perch (Scortum barcoo) as Case Example

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RECENT ADVANCES IN FINFISH & CRUSTACEAN AQUACULTUREFriday 25 Oct 2019

Nanyang Polytechnic

1. Background on jade perch

2. Spawning of jade perch

3. Larviculture trial

4. Salinity tolerance trial

5. Summary

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Outline

• Jade perch (aka Barcoo grunter) is a freshwater finfish species native to Australia

• Commonly farmed in Australia, Malaysia and China.

• It’s hardy and a fast grower (reach market size in 7 months)

• Omnivorous: feed on zooplankton, small crustaceans, aquatic insects, algae, etc

Lake Eyre basin

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Greenish, jade-like speckle

Background on jade perch

Introduction

• High Omega-3

• High nutritional value

• Good taste

• High market value

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Background on jade perch

Advantages of jade perch

Item Weight (gm) Percentage Omega-3 per 100 gm

Whole fish 791.78 100% -

Muscle-back 270.30 34.14% 5660 mg

Muscle-belly 112.92 14.26% 7069 mg

Fillet total 383.22 48.40% 6075 mg

Fat 96.60 12.20% -

• Fillet from jade perch cultured at MAC was sent for Omega-3 testing.

• The average omega-3 content per 100 gm of fish fillet is 6075 mg.

• Source of Fish: Australia (imported as fry)• Age: 2 years old• Stocking density: 2 – 5 kg/m3

• Feeding: Dry pellets supplemented with shrimp

• Broodstock were measured and tagged for individual identification.

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Spawning of jade perch

Broodstock development

There are local farms expressing interest to spawn jade perch locally to reduce reliance on overseas fry supply.

Genital pore Urinary poreAnus Anus Urogenital pore

1) Number of visible openings

Female Male

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Spawning of jade perch

Identification of females and males

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2) SizeAvg weight of males = 0.9 kgAvg weight of females = 1.2 kg

3) Sampling of eggs and milt:Females egg size: ~850 um (uniform size)Males: Flowing milt with gentle massage (sperm stops moving after 2 mins)

Sex ratio of selected males to females is 1:1

Male

Female

Spawning of jade perch

Broodstock fish selection

Injection of Ovaprim (Salmon Gonadotropin Releasing Hormone Analog 20 µg/ml + Domperidone 10 mg/ml)• 0.5 ml per kg as per manufacturer instructions• Used 1 ml sterile syringe and 25G size needle• Intra-peritoneal injection instead of intra-muscular injection.• Temperature: 27-29 ⁰C

Spawning tankInjection

8*To allow Ovaprim to reach room temperature before injection to reduce viscosity

Spawning of jade perch

Hormonal Induction

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Environment

GnRH(+)

Dopamine(-)

LH FSH

Brain

Pituitary

Gonad

AndrogensEstrogens

Progestagen

Full growth gametes

Fertile gametes

Female

Estrogens

Liver

Ovary

Vitellogenin

Vitellogenesis

Oocyte with yolk

Progestagen

Final maturation

Male

Testis

Spermatogenesis

Androgens

Final maturation

Progestagen

Spawning of jade perch

Brain-Pituitary-Gonad Axis

Stocking density: 1,075 eggs/L

Water exchange rate: 30% per hr

➢ Spawning occurred at 26-28 hours after injection.➢ In total 430,000 fertilized eggs were collected and stocked into a 400 L fiber glass hatching tank after

spawning.➢ The eggs hatched at 16-18 hours post fertilization.➢ In total 202,500 larvae hatched out (46% hatching rate)

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Spawning of jade perch

Spawning on the next day

• The average size of eggs and larvae is 2mm.

• Larvae hatched out around 18 hpf.

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Larviculture trial

Different stages of embryonic and early larval developmentPicture Embryonic Period Time After

Fertilization

A to D Cleavage 1.2 – 1.4 hr

E to F Blastula 2.5 – 4.5 hr

G to H Gastrula 4.5 – 7.0 hr

I Neurula 7.0 – 8.5 hr

J to K Organogenesis 8.5 – 12.5 hr

L Hatching 14.5 hr

Tank type Indoor/Outdoor

0.5 m3 fiber tank Indoor

1.2 m3 fiber tank Indoor

1.2 m3 concrete tank Outdoor

The larvae were stocked into 3 different types of larviculture tanks at the density of 15 pcs/L

1.2 m3 fiber tank0.5 m3 fiber tank 1.2 m3 concrete tank 12

Larviculture trial

Stocking

0 dph

Rotifers

2 dph 4 dph

Moina

Dry feed

Harvesting rotifers from the ponds Size comparison between 4 dph larvae and unfiltered Moina

7 dph 14 dph

3 dph

8-9 dph

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Larviculture trial

Feeding protocol

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Cannibalism observed since 7 dph• In total 13,000 fry were weaned to dry

feed at 15 dph.• Grading was done to seperate fish of

different sizes.

Larviculture trial

Grading and weaning

Key observations:

• Feeding of rotifer and dry feed can start from 3 dph and 9 dph.

• Jade perch was highly cannibalistic from 7 dph.

• Tanks with longer exposure to direct sunlight and higher temperature have visually faster growth.

• Using bigger tanks for larviculture are recommended as the water parameters tend to be more stable.

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Larviculture trial

• Although it’s a fresh water species, the early stage of its larviculture is similar to marine fish species, which requires live feeds such as rotifer and Moina/Artemia

• Nutritional requirements of the larvae to be investigated

To investigate the effects of salinity on jade perch growth performance and survival rate• 50 pcs of jade perch in a 2.5 ton tank• 5 experimental tanks with different salinities

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Salinity tolerance trial

Experiment setup

Quarantine (1 month) Acclimatization (3 months) Growth measurement (4 months)

Salinity (ppt) 1st month 2nd month 3rd month 4th month

0 Normal Normal Normal Normal

10 Normal Normal Normal Depressed

20 Normal Normal Depressed Depressed

25 Normal Depressed Depressed Depressed

30 Depressed Depressed Depressed Depressed

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Salinity tolerance trial

Results - Feeding Behaviour

• Jade perch was fed twice daily based on 2% body weight using auto feeder and/or hand feeding.

• Depressed appetite was observed in all brackish and sea water groups.• Uneaten feed was siphoned away and weighed for FCR measurements.

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Salinity tolerance trial

Results - Swimming and Rest Activity

0

10

20

30

40

50

60

70

80

0

20

40

60

80

100

0‰ 10‰ 20‰ 25‰ 30‰

Tim

e Sp

ent

(%)

rest

ing

Tim

e Sp

ent

(%)

swim

min

g

Salinity

Swimming and Rest Activity (%)

Swim(%) Rest(%)

As the salinity increases, the fish swim less and prefer to stay more at the tank bottom.

Water Column Preference

1%

9%

90%

0‰

Bottom Middle Top

5.3410.01

84.66

10‰

Bottom Middle Top

47.99

49.6

2.4

20‰

Bottom Middle Top

34.54

65.46

25‰

Bottom Middle Top

68.7

31.3

30‰

Bottom Middle Top

Time spent (%) on the different water columnTime spent (%) on swimming and resting

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0

50

100

150

200

250

300

350

400

0 1 2 3 4

Mea

n w

eigh

t (g

)

Month

Mean Weight of Jade perch

0‰ 10‰ 20‰ 25‰ 30‰

Salinity tolerance trial

Results - Growth Performance

MONTH 0‰ 10‰ 20‰ 25‰ 30‰

0 69.06±9.6 72.88±10.9 64.68±7.7 71.51±8.2 61.61±7.3

1 112.36±14.0 114.52±15.2 105.53±12.3 108.52±23.5 67.09±9.7

2 167±21.2 165.2±20.8 150.1±18.7 127.7±35.5 63.5±9.3

3 244.4±32.9 234.2±24.5 196.3±28.5 145±43.6 76.8±13.3

4 357.5±40.9 331.2±39.8 233.2±40.8 165.7±50.7 88.5±18.0

Mean weight(g) of control and 4-salinity treatment groups in the different months

As the salinity increases, the fish in 20 – 30 ppt groups grew slower.

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Salinity tolerance trial

Results - Survival Rate

0

5

10

15

20

25

30

35

40

45

50

0 10 20 25 30

Surv

ivab

ility

Months

Survivability

1 2 3 4

Salinity (ppt) Survival rate

0 98%

10 96%

20 90%

25 88%

30 72%

Survival rate is negatively affected in increased salinity.

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0‰ 10‰ 20‰ 25‰ 30‰

SGR(%) 1.29 1.19 1.01 0.66 0.29

FCR 1.31 1.42 1.68 1.89 4.02

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

SGR (%) and FCR

SGR(%) FCR

Salinity tolerance trial

Results - Other Growth Performance Indicators

• As the salinity increases, the specific growth rate (%/day) decreases while the FCR increases.• Probably due to the energetically demanding osmoregulative mechanisms associated with

salinity stress

• Jade perch can be bred and cultured locally in Singapore.

• Although it’s a fresh water species, the early stage of its larviculture is similar to marine fish species, which requires live feeds such as rotifer and Moina/Artemia. Thus rotifer production needs to be set up.

• Its growth and survival are negatively affected in brackish and saline condition (salinity ≥20 ppt) probably due to additional osmoregulation and salinity stress.

• Jade perch is gaining popularity in local land-based farms as an ideal species for indoor RAS and aquaponics system owing to its high value and nutrition.

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Summary

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