live feeds and its role in health management

8/18/2019 Live Feeds and Its Role in Health Management

1/22

Live feeds

&its role in health management inthe larviculture of brackishwater

nsh and shell shes

Sandeep K P., K P Kumaraguru vasagam and Syama ayal, !.

"utrition #enetics & $iotechnology ivision, %$', %hennai


2/22

Introduction

• Aquaculture is one of the fastest growing food producing

sectors in the world, accounting for almost half of the

total food sh supply (FAO, 201!

•

Importance of hatchery production• "hat are li#e feeds$

• Importance of li#e feeds in lar#iculture

•

Living capsules of nutrition%• &reen water techniques in hatcheries

• 'ealth management of nsh and shellsh lar#ae

through li#e feeds


3/22

i#e feeds$•

Aquatic animals at the time of rst feeding are fragile anddelicate%

– ((ost critical phase!

• In nature they feed on phytoplan)ton and *ooplan)ton

• i#e feeds consist of phytoplan)ton and *ooplan)ton gra*edupon +y economically important shes%

• uch diet pro#ide

– -road spectrum composition of food

– -etter inta)e (swimming.mo#ement!

– /ich in essential nutrients

–

Autodigestion characteristics – Facilitate +etter nutrient assimilation in lar#ae

– timulate feeding +eha#iour with its soft teture andattracta+ility

• o li#e food organisms are )nown as living capsules ofnutrition3


4/22

Important li#e feeds in aquaculture

). (icroalgae

*. nfusoria

+. otifers

-. 'rtemia

% %opepod

/. %ladocerans

0. 1ubife2

3. %hironomid larvae


5/22

' simple food web representing

larval feeding (ource4 FAO 5echnical paper4 671!


6/22

8icroalgae• 9ssential food source in rearing of

– lar#ae of marine and +rac)ishwater nsh, shrimps,food for *ooplan)ton (/otifers, :opepods andArtemia!

• i*e 4 few micrometers to 100 ;m

• :ommonly used species are

– diatoms (Skeletonema costatum, Chaetocerosgracilis, Thalassiosira pseudonana!

– !, car+ohydrate (=%=26>! and lipid (?26>!%


7/22

0

=

10

1=

20

2=

60

6=

Lipid content in di4erent microalgae

'lgal species

5 of 6

5he presence of highly unsaturated fatty acids ('@FA!, inparticular eicosapentaenoic acid (204=n6, 9A!, arachidonic acid(204n7, A/A!, and docosaheaenoic acid (2247n6, B'A!, is ofmaCor importance in the e#aluation of the nutritional composition

of an algal species to +e used as food for marine and+rac)ishwater lar#al nutrition%


8/22

Skeletonema costatum Chaetoceros calcitrans Thalassiosira pseudonana

Chlorella vulgaris Dunaliella salina Tetraselmis


9/22

/otifers


10/22

• /otifers are popularly called as wheel animalcules%

• Brachionus plicatilis and B rotundiformes are the mostimportant species used in aquahatcheries forlar#iculture%

• Bepending on the mouth si*e of cultured organisms,small (=0100 ;m! or large (100200 ;m! rotifers areused%

• 5he nutritional #alue of rotifers mainly depends on theirfood%

• cope for enrichment%


11/22

Artemia• 8ost widely used li#e food in aquaculture

• It is an organism closely related to shrimp +elonging toorder Anostraca of the class :rustacea%

• 5here are more than =0 geographical strains of Artemiahas +een identied%

• Annually, o#er D000 metric tons of dry !rtemia cystsare mar)eted worldwide for onsite hatching into 0%mm nauplii

• 5he +iggest plus point of using artemia is that Artemianauplii can +e produced on demand from dormantcyst upon immersion in seawater they regain theirmeta+olic acti#ity and within 2 hours free swimmingnauplii will come out%


12/22


13/22

:opepods• :opepods are di#erse group of animals +elonging to the

class :rustacea with more than 10,000 species indiEerent ecological niches%

• 5hree maCor groups of free li#ing copepods are:yclopoids, :alanoids and 'erpecticoids%

• :opepods are +etter li#e feeds for aquaculture comparedto artemia or rotifers +ecause of the adequate nutritional#alue, si*e #ariation, and swimming +eha#iour

• @sing rotifers and Artemia during this early period in life

history does not always promote optimal lar#al growthsince these li#e preys may contain an inadequate fattyacid prole and, in some cases, +e of an inappropriate

si*e%


14/22

%alanoid

7er acticoid

%yclipoid

i h l h i f h


15/22

:reating a healthy en#ironment for thelar#ae

Larval

health

Environment

Feed

Biosecurity

Pathogen

• 5he factors which determine the lar#al health and sur#i#al areproper en#ironment, suita+le feed at right time, a+sence ofpathogens and o#erall +iosecurity%

•

A green water system or the presence of certain microalgae canma)e all the essential requirements for +etter lar#al health%


16/22

&reen water system

• 5he presence of microalgae in the lar#al rearing tan)will impro#e and sta+ili*e the water quality in staticsystems4 green "ater system

• 5he eEect of microalgae in sh lar#al rearing system isnot completely understood%

• 5he hypotheses listed in scientic studies include – impro#ement of water quality (remo#al of ammonia

and :O2!,

– direct nutrition through acti#e ingestion,

–

indirect nutrition +y enriching the li#e prey in therearing tan),

– micronutrient stimulus for feeding +eha#iour orphysiological processes,

– regulation of opportunistic +acteria +y anti+acterialor pro+iotic action


17/22

&reen water system in lar#al rearing tan)s


18/22

:ommercial algal culture and itsapplications

Species 8se in a9uaculture

Nannochlor opsis &rowing rotifers and in n sh hatcheries#ery high 9Ale#elPavlova @sed to increase the B'A.9A le#els in oysters, clams,

mussels and scallopsIsochrysis 9nrichment of *ooplan)ton such as artemia, used in

shellsh hatcheries and used in some shrimp hatcheries,

good si*e for feeding +rine shrimp and copepods, oysters,

clams, mussels, and scallopsTetraselmis 9cellent feed for shrimp lar#ae and contains natural

amino acids that stimulate feeding in marine animals,

used in conCunction with

Nannochloropsis for producing rotifers, ecellent feed forincreasing growth rates and ghting *oea syndrome

Thalassiosir

aweissfogii

@sed in the shrimp and shellsh lar#iculture, considered

+y se#eral

hatcheries to +e the single +est alga for lar#al shrimps,

also good for

feeding copepods and +rine shrimps


19/22

Antimicro+ial property of microalgae

• "idespread anti+iotic resistance among pathogenic +acteria

and the low specicity of these drugs made an urgent need forthe de#elopment of no#el anti+acterial agents%

• Addition of microalgae (green "ater system! often has apositi#e eEect on the sur#i#al rates of nsh and shellshlar#ae%

• 8icroalgae ha#e +een eplored for their +ioacti#e compoundswith promising applications consisting anti+acterial, anti#iraland antifungal acti#ities%

• A sta+le transgenic line of Nannochloropsis oculata which has+actericidal acti#ity was de#eloped%

• -y feeding this transgenic N oculatato a small model shmeda)a, signicant increase in the sur#i#al rate was o+ser#ed2 hours after +acterial pathogenic infection with #ibrio

parahaemolyticus in the shGs digesti#e tract%

Application of transgenic microalgae


20/22

Application of other li#e feeds inlar#iculture

• Other li#e feeds li)e rotifers, artemia and copepods are alsowidely used in lar#iculture in diEerent lar#al stages of diEerentspecies%

• 5he rotifers and artemia can +e enriched with suita+lemicroalgae or commercial enrichment product to get +etterlar#al sur#i#al and health%

• 5he copepods are nutritionally superior to artemia androtifers%

• 5he +road range of si*e (60 ; to 1 mm! of copepods is also

suita+le for marine lar#iculture%• @nfortunately the usage of copepods in hatchery operations

are limited as the single species mass culture of copepods arenot yet standardi*ed in many countries and it is #ery diHcult%


21/22

:onclusion

• i#e microalgae with high nutriti#e #alue andappropriate physical properties can pro#ide ahealthy rearing en#ironment to the aquaculture

system%• A +etter understanding of the mechanism of green

"ater systems +oth in intensi#e and etensi#eculture will aid in optimi*ing the usage of

microalgae in lar#al culture%• Further research has to +e done on the eact

mechanisms on the impro#ement of growth,sur#i#al and health of nsh and shellsh lar#ae +y

diEerent microalgae%


22/22

5han)you

live feeds and its role in health management

Documents