Rotifer(Brachionus rotundiformis) Culture Technology for Hatchery

Production in Singapore XuQunying

ScientistMarineAquacultureCentre

AquaSG18’4thOctober-2018

CONTENT

Background

KeychallengesofrotifercultureinSingapore

Analysis&SolutionsUnstablerotifertreatmentQualityrotiferdietRecirculatingRotiferCultureSystemGoodmanagementprotocol

Summary

1

2

3

4

Background

Part One

AVAVisionandMission

KeyR&Dinitiatives@MAC

Rotiferintroduction

MarineAquacultureCentre(MAC)

0 1

TypesofrotifercultureinSingapore

AVAVisionandMission

�4

➢ Official Opening in 2003

➢ Spearhead tropical aquaculture technology development for large scale hatchery and fish farming systems

➢ Key R&D initiatives include: • Selective Breeding programme • Large-scale fry production technology

• Development of new species • Aquaculture systems

➢ Industry Extension

➢ Learning Journeys and Trainings

�5

Marine Aquaculture Centre (MAC)

Key R&D Initiatives @MAC

�6LiveFeeds

Large-Scale Fry Production Technology

�7

RotiferIntroduction

• Rotifersareusedextensivelyinaquaculture➢ Optimalsizeforfishlarvae,shellfish,

coralsandotherfilterfeeders➢ Goodnutritionalprofileifproperly

enriched➢ Highreproductionrate➢ Easytoculture

RotiferIntroduction– CommonlyUsedSpecies

B.plicatilis(L)

171-238µm

Low-temperatures20-25oC

Euryhaline

B.rotundiformis(S)

121-162µm

High-temperatures28-35oC

Low-salinities

RotiferLifeCycle

AsexualandSexual

Nearlyalltherotifersseeninnaturearefemales

Malesoccuronlyforshortperiods

Lifespanofamicticfemales:7-12days

Numberofeggsforamicticfemalesproducedperday:~5eggs

Schematic explanations of sexual and asexual cycles of reproduction of rotifer Brachionus (Lubzens and Zmora 2003)

�10

WaterQuality&Feed

➢WaterQuality1. Dissolvedoxygen→Above4ppm

2. pH→7.5–8.5

3. UnionizedAmmonia→lessthan

1ppm

4. Salinity→10-25ppt

5. Temperature→28-35oC

➢Feed1. Rotifersarefilterfeeders

2. Preysizespectrum→

1.4–21µmindiameter

3. Needtofeedevery4hours

4. Foodpreferences→

microalgae,yeast,bacteria

TypesofRotiferCultureinSingapore:OutdoorPond

Pondsize:1200m2Pondsize:120m2Tanksize:20m2

Density:

20-50 ind/ml

Productivity:10 mil rotifer

produced per m3 per day

Manpower:

0.39 hr to produce 100 mil rotifer

per day

Ponds needed to

start production:

3-5

Tanksize:8m3Tanksize:2.5m3Tanksize:1m3

Density:

200-500 ind/ml

Productivity:100mil rotifer

produced per m3 per day

Manpower:

0.87 hr to produce 100 mil rotifer

per day

Tanks needed:

5-8

TypesofRotiferCultureinSingapore:IndoorBatchCulture

KeyChallengesofRotiferCultureinSingapore

Part Two

Maintainrotiferculturestability

0 2

Producinghygienicrotifers

Producingrotiferswithgoodnutrition

MaintainRotiferCultureStability

Tota

l (m

il)

0

425

850

1275

1700

26/2 2/3 6/3 10/3 14/3 18/3 22/326/3 30/3 3/4 7/4 11/4 15/4

Tota

l (m

il)

0

750

1500

2250

3000

17/1 21/125/1 29/1 2/2 6/2 10/2 14/2 18/2 22/2 26/2 2/3 6/3

Total No of rotifer (mil)Series2Series3Series4Series5Series6Series7Series8Series9Series10Series11Series12Series13Series14Series15Series16Series17Series18Density (ind/ml)Eggs carrier (%)Algae Feed (L)Flush & supply (mil)Daily increase (%)

Tota

l (m

il)

0

425

850

1275

1700

7/3 10/3 13/3 16/3 19/3 22/3 25/3 28/3 31/3 3/4

00

Tota

l (m

il)

0

300

600

900

1200

Date17/8 22/8 27/8 1/9 6/9 11/9 16/9 21/9 26/9 1/10 6/10

1strotifercrashin2017 2ndand3rdrotifercrashin2017

5throtifercrash4throtifercrashin2017

ProducingRotiferswithGoodNutrition

DocosahexaenoicAcid(DHA)Anessentialfattyacidthataccumulatesinthebrainoffishduringearlydevelopmentwhereitincreasesneuralfunctions

1

2

3

EicosapentaenoicAcid(EPA)EPAistheprimarymediatorofcellularinflammation

ArachidonicAcid(AA)AAbeingthepreferredsubstrateandproducingeicosanoidsofhigherbiologicalactivity

ProducingHygienicRotifers

1

2

3

4

Bacteria:harmfultypescauseunexpectedmortalitytorotifers;detrimentaleffectonfishlarvae.

Vibrio:pathogenictofishwhenintroducedtofishlarvaetankswithculturedrotifers.

Fungal:reduceproductivityofrotifermassculturesandabnormalmortality.

Ciliates:mayreleasegrowth-inhibitingsubstanceintothewaterandretardfishgrowth.

×××

×

Analysis&Solutions

Part Three

TreatmentforRotiferswithUnstableGrowth

RecirculatingRotiferCultureSystem

0 3

GoodManagementProtocol

ProperEnrichmentofRotifers

1

2

3

4

�18

Treatment for Rotifers with Unstable Growth

Healthyrotiferculture

Unhealthyrotiferculture

Eggcarriers High Low

Movement Active Lethargic

Ciliates Noneorfew Alot

Clumps No Alargenumber

Gutcontent Full Empty 0

0.4

0.8

1.2

1.6

1.3mm/s 1.5mm/s 0.6mm/s 0.4mm/s

Signsofunstablerotiferculture

1

Slow-movingrotifers

Activerotifers

Averageswimmingspeedofrotifer

�19

Reasons for unstable rotifer:➢Poorwaterquality

➢Pathogenicbacteriainfection

➢Ciliatesandcopepod

➢Overorunder-feeding

• Infectedrotiferscauseadetrimentaleffectonfishlarvae

Ciliatesvideo

Treatment for Rotifers with Unstable Growth1

Uronema in rotifer

UnstablerotiferculturetreatedwithlivemicroalgaeatMAC➢ Theunstablerotiferculture

recoveredandbecamestable

➢ Grewfrom300milto1billionwithin8days

➢ However,rotifersremainedunstableinthecontroltank

➢ Microalgaehaspositiveeffectonthebacterialloadinrotiferculturetank

Solution: Live Microalgae Treatment

1

0

350

700

1050

1400

6/10 10/10 15/10 19/10 24/10

300365 356

403 403331

411 385419

451 447478 479

404332

223

1126

1023

1260

10501002

1180

974

1250

10001018

1282

1000.6

1116

300

389443

486

768 740 762831

1082

Co-feedingwithalgae

Withoutalgae

(Control)

Unstablerotifer→Stablerotifer

54

200

308

11681

Flush&supply(mil)

Date

Rotifernum

ber(mil)

ConcentratedMicroalgaeInsteadofLiveMicroalgae

Benefits:

➢ Concentratedmicroalgaeisalive

comparedtocommercially-

availablefreeze-driedmicroalgae

➢ Notharmfultofishlarvae

➢ Easytotransport

➢ Canbestoredforupto6months

ormore

�21

AtMACweconcentratelivemicroalgaeforeaseofstorage,transportanduse.

Growthchartofresuspenedmicroalgae(mil/ml)

0.0

5.0

10.0

15.0

20.0

24Mar 27Mar 31Mar 4Apr 8Apr

5.36.3

7.18.2

9.6

13.714.5

16.8 17.518.99

1

�22

Proper Enrichment of Rotifers

CommercialenrichmentproductsEnrichmentincludes:

➢ Short-termenrichment

➢ Long-termenrichment

Enrichmentfood:

➢ Microalgae

➢ Oilemulsions

➢ Formulateddiets

Instantmicroalgae

AlgaMac

FreshChlorella

Selco®S.parkle

2

➢ Treatment of unstable rotifer culture

• Immediate adding of live microalgae

➢ Prevention of disease

• Treat water with filter and UV

• Personal hygiene

• Equipment and culture area disinfection

Good Management Protocol

�23

3

Uronema

Euplotes

~18-28 µm

~80 µm

Recirculating Rotifer Culture System

Rotiferculturetank Net

Waterpump

Biofiltertank

Proteinskimmer

➢ 2.5m3culturetank➢ 45µmnet➢ Proteinskimmer➢ Biofilter➢ Peristalticpump

PP

Feed

4

Issue:Clogging

Solution:Movablescreen

RotiferNetCloggingIssue

➢Rotifernetiseasilycloggedbydebrisandfoam.

➢ Strongaerationhelpedtocleanthenet,andeliminatethenumberofrotifersgoingthoughthenet

4

Recirculating Rotifer Culture System

Advantage:

➢Morehygienic

➢ Higherdensity

➢ Higherproductivity

➢ Lessmanpower

➢ Stable

4

Comparison of Different Culture Systems

Outdoor pond culture

Indoor batch culture RAS continuous culture

Volume: 1200 m3 2 m3 2.5 m3

Density: 20-50 ind/ml 200-500 ind/ml 800-1000 ind/ml

Productivity: (rotifer produced per

m3 per day)10 mil 100 mil 200 mil

Manpower: (produce 100 million

rotifer per day)0.39 hr 0.87 hr 0.39 hr

4

High Density Rotifer in Recirculating Rotifer Culture System

➢Highdensity:3000-4000ind/ml➢Compact➢Stable➢Continuoussupply➢Highproductivity

0

1125

2250

3375

4500

0 1 2 3 4 5 6 7 8 9 10 11 12 1314 1516

Total No of rotifer (mil)Series2Series3Series4Series5Series6Series7Series8Series9Series10Density (ind/ml)Egg carrier (%)SPK Feeding rate (g/mil)Algae Feed (L)Flush & supply (mil)Daily increase (%)

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4460

3000

00000000000000 000000000000000

3480

3000

0000000000000 0000000000000000

4090

3000

000000000000 00000000000000000

3830

3070

00000000000 000000000000000000

3870

29602830

2120

00000000 000000000000000000000

26202740

0000000 0000000000000000000000

3440

2830

000000 00000000000000000000000

3530

2720

00000 000000000000000000000000

3220

25102650

17501540

1000

000000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0 0 0 0

3000

4460

0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0 0 0

3000

3480

0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0 0

3000

4090

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0

3070

3830

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0

2120

28302960

3870

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0

27402620

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0

2830

3440

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0

2720

3530

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

1000

15401750

26502510

3220

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

4

Improvement in Rotifer Growth Rate

Averagedailygrowthrate

0%

18%

35%

53%

70%

Mar-22 Apr-22 May-22 Jun-22 Jul-22 Aug-22 Sept-22

64%

40%38%

47%

23%

13%10%

Others: Protocols to Enhance Rotifer Growth Rates (On going)

Preliminaryobservations:➢ Rotifergrew1000times

from4milto4bilwithin11daysat10ppt.

➢ Dailygrowthrateis150%,whichishigherthan30ppt.

Benefits:➢ Savemanpower➢ Savecost➢ Increaseproductivity➢ Reducepreparationtime

10ppt 30ppt

Dailygrowthrate 150% 95%

Ronfergrowthwithdifferentsalinity

Quann

ty(m

il)

0

1025

2050

3075

4100

Day

0 1 2 3 4 5 6 7 8 9 10 11

4 2.4 6.8 53.6446.8 77.5

375 477

852.5

1207.8

2600

4040

10ppt30ppt

Summary&Futurestudy

Part Four

0 4

Summary

FutureStudy

ProducerotifersintensivelyandconsistentlyonasmallfootprintisimportantforSingaporehatcheries

�32

Summary

1

Livemicroalgaetreatmentisoneofthesolutionstotreatunstablerotiferculture

RecirculatingRotiferCultureimprovesproductivityandcansupportlarge-scalehatcheryproduction

2

3

Transferthetechnologytolocalfishfarm

Protocolstoenhancerotifergrowthrates

�33

Future Study

1

2

�34

Thankyou!