ZOOPLANKTON PRODUCTION IN AQUACULTURE

Assoc. Prof. Serpil SERDAR

Ege University, Faculty of Fisheries

Plankton: the aggregate of passively floating, drifting, or somewhat motile organisms in pelagic zone

PhytoplanktonZooplankton

ChlorophyceaeChlorophyceae RotiferaRotifera

PrasinophyceaePrasinophyceae ArtemiaArtemia

BacillariophyceaeBacillariophyceae CopepodCopepod

HaptophyceaeHaptophyceae DaphniaDaphnia

ChrysophyceaeChrysophyceae

CyanophyceaeCyanophyceae

CryptophyceaeCryptophyceae

Phylum: Rotifera

Classis: Seisionidea

Classis: Bdelloidea

Classis: Monogononta

These species is distributed fresh water, brackish water and marine water and nearly 90 % rate live in fresh water.

Rotifera phylum is the most important zooplankton group in aquatic systems includes 3 classis, 120 genus and approximately 2000 species.

Keratella cochlearis

Keratella longispina Asplanchna priodontaPhilodina acuticornis

Brachionus calyciflorusBrachionus rubens

Freshwater rotifer species

Morphlogy

Rotiferlerde vücut baş, gövde ve kuyruk olmak üzere 3 bölgeden oluşmaktadır.

The body of most rotifers is divided into three portions: head, trunk and foot. The head carries a corona which is surrounded by cilia 

The rotifer Brachionus plicatilis is divided into two types

so-called L and S types by morphological, physiological

and genetical characteristics

L type - Brachionis plicatilis 200-340 µm

S type - Brachionis rotundiformis 150-220 µm

SS type - Brachionis rotundiformis 70-160 µm

-They have distinguishing characteristics

such as size, body shape and shape of

their anterior spines

-Digestion rate of L-type is 1.7 times is

more than S-type

- Optimal water temperature

S-type 28-35ºC

L-type 18-25ºC

- The lowest water temperature limit

S-type 20 ºC

L-type 10 ºC

-S-type

diploid female 25 (2n=25) chromosome

haploid male 12 (n=12) chromosome

-L-type

diploid female 22 (2n=22) chromosome

haploid male 11 (n=11) chromosome

L- biotypes

(220-340 µm)

SM biotypes

(150-220 µm)

S and SS biotypes

(100-150 µm)

B. plicatilis

B. manjavacas

B. ʹNevadaʹ

B. ʹAustriaʹ

B. ibericus

B. ʹcoyrecupiensisʹ

B. ʹalmenara ʹ

B. ʹtiscarʹ

B. ʹcaymanʹ

B. ʹtowerinniensisʹ

B. rotundiformis

B. ʹlostʹ

L, large; SM, medium; S and SS, small and super small. The numbersindicate the approximate range of adult’s body length in each group

REPRODUCTION

Asexual and sexual reproduction in Brachionus plicatilis

*Amictic female produces 20 or more eggs in 7-10 days

*Mictic female produces 1-3 eggs in the same period

Why does start formation of resting egg?

* Suddenly change of temperature and salinity in the culture medium

* Reduce of culture medium quality

*Change of food type, quality and quantity

* High population density

* Genetic structure of rotifers

Mictic and amictic female

* After parthenogenetic reproduction, amictic female produce diploid eggs

which are oval shape and grey colour and after hatching, amictic or mictic

female emerge

* After meiosis, mictic female produce haploid eggs which are round shape,

grey colour and half of amictic egg size. After hatching, male rotifer emerge

*After meiosis, mictic female produce fertilized eggs (diploid) which are oval

shape, brown or orange colour cytoplasm and small part of egg has

transparent space

Rotifer species have contributed to the successful hatchery production of more than 60 marine finfish species and 18 species of crustaceans. Brachionus plicatilis is one of the most popular and important species

Culture history of B. plicatilis

Early 1950s rotifer population rapid and suddenly increased in eel ponds

(Mizukawari phenomena)

1964 daily tank transfer method improved

1960 mass culture techniques explored

1965 discovered to be excellent food for red sea bream larvae

1967 discovered that baker’s yeast is a suitable food source

1970s baker’s yeast was used extensively in mass culture

* Rotifers are ideal as a first exogenous food source due to their small size

*Slow swimming speed and habit of staying suspended in the water column

* Ability to be cultured at high densities

*High reproductive rate

*Their swim speed is suitable to larvae for catching easily without huge

cost

* isolation from natural area is easy

*you can culture in a small scale tank in a high density

*Amount of calorie content is approximately 4x104 cal and it can easily be

enriched with fatty acids or vitamins can be easily

*Due to parthenogenesis cycle, continuously produce new generation and

population increase rapidly

*Reaching egg formation in a short time

Why rotifer is important for early feeding in aquaculture?

Culture conditions

*Although Brachionus plicatilis is known for its ability to tolerate a wide range of salinity between 1 %0 and 97 %0, optimal reproduction can take place at salinities below 35 %0. *The choice of the optimal culture temperature for rearing rotifers depends on the rotifer type; L-strain rotifers (18-25ºC) being reared at lower temperatures than S-type rotifers (28-35ºC).

Temperature (°C) 15 20 25Time for embryonic development (days) 1.3 1 0.6

Time for young female to spawn for the first time (days)

3 1.9 1.3

Internal between two spawning (hours) 7.0 5.3 4.0

Length of life (days) 15 10 7

Number of eggs spawned by a female during her life

23 23 20

Rotifers can survive in water containing as low as 2 mg/l of dissolved oxygen. The best growth rates occur approximately at a temperature between 20 and 35 °C, a salinity of 10-35 %0 and a pH of 7.0-9.0

*Brachionus calyciflorus and Brachionus rubens are the most commonly

cultured rotifers in freshwater mass cultures.

*They tolerate temperatures between 15 to 31°C.

*The optimal pH is 6-8 at 25 °C,

*Minimum Oxygen levels are 1.2 mg.l-1.

Culture conditions of freshwater rotifers

FEEDING

Nannochloropsis oculata

Chlorella sp.

Dunaliella tertiolecta

Tetraselmis suecica

Isochrysis galbana

Monochrysis lutheri

The rotifer is the planktonic suspension feeders. These organisms filter

small particles (2-20 µm) out of the water column by means of a ciliated

corona located on the anterior portion of the body. Microalgae is commonly

used as feed, often together with baker’s yeast and artificial diets (Culture

Selco® and Roti-Rich). Filtration and ingestion rates are influenced by food

type, mainly the presence or absence of a cell wall, critical cell density, cell

size, type of rotifer, and culture conditions such as water temperature,

salinity and O2.The most common phytoplankton species in rotifer feeding

Marine species Freshwater speciesScenedesmus costato-granulatus

Kirchneriella contorta,

Phacus pyrum,

Ankistrodesmus convoluus

A rotifer can eat 200 cells/minute under optimal conditions

Rotifer (ind./ml) Baker’s yeast

0-100 1.3 g/106

100-200 1.0 g/106

200-300 0.75 g/106

300< 0.5 g/106

Rotifer density. ml-1 Culture Selco®

100-150 0.53 g/106

150-200 0.47 g/106

200-250 0.40 g/106

250-300 0.37 g/106

300-350 0.33 g/106

350-400 0.30 g/106

Culture Systems

* Batch

* Semi-continuous

* Continuous

The first method (long term)

produces an enrichment of the

tissues, as it is continuous along

the entire culture period

The second system is a short

term enrichment. It implies the

harvesting and rinsing of the

rotifers and the preparation of

a separate enrichment tank

Rotifer biochemical composition is of primary importance for larval

nutrition. The lipid and essential fatty acids profile is relatively modifiable

by dietary manipulation. Baker’s yeast and some microalgae species

support high population growth but the rotifers produced are nutritionally

deficient or poorly balanced in the lipid fraction as larval food. In order to

achieve an appropriate content of essential fatty acids, rotifers can be

enriched with microalgae, handmade, marine oil emulsions, prepared

microparticulated feeds and commercial products.

Conceiçao, L. E., Yufera, M., Makridis, P., Morais, S., Dinis, M.T. 2010. Live Feeds For Early Stages of Fish Rearing. Aquaculrure Research, 41, 613-640.

Fulks, W., Main, K.L., 1991. Rotifer and Microalgae Culture Systems. Proceedings of a U.S.-Asia Workshop. Hawaii, pp.3-52

Fu, Y., Hirayama,K., Natsukari, Y. 1991a. Genetik divergence between S and L type strains of the rotifer Brachionus plicatilis O.F.Müller. J. Exp. Mar. Biol. Ecol., 151, 43-56

Fu, Y., Hirayama, K., Natsukari, Y.1991b. Morphological differences between two types of the rotifer Brachionus plicatilis O.F.Müller. J. Exp. Mar. Biol. Ecol., 151, 29-41.

Gomez A., Serra M., Carvalho G.R. & Lunt D.H. (2002) Speciantion in anvcient cryptic species complexes: evidence from themolecular phylogeny of Brachionus plicatilis (Rotifera). Evolution 56,1431-1444.

Hindioğlu, A., Serdar, S., (2001). The Effect of Different Dilution Rates on Rotifer (Brachionus plicatilis Müller, 1786) Culture TÜBİTAK, Tr. J. of Veterinary and Animal Sciences, 25: 483-487 (English abstract).

Lavens, P., Sorgeloos, P. 1996. Manual on the production and use of live food for aquaculture. FAO Fisheries Technical Paper, 361.

Lubzens, E., Tandler, A., Minkoff, G. 1989. Rotifers as food in aquaculture. Hydrobiologia. 186/187: 387-400.

Lubzens, E 1987. Raising rotifers for use in aquaculture. Hydrobiologia 147: 245-255.

Moretti, A., Fernandez-Criado, M. P., Cittolin, G., Guidastri, R. 1999. Manual on Hatchery Production of Seabass and Gilthead Seabream, Volume 1. FAO Fisheries Technical Paper

Serdar, S., Hindioğlu(Lök), A. (1999) Advantages and disadvantages of resting egg formation in rotifer (Brachionus plicatilis (O.F.Müller 1786)) culture. Journal of Fisheries and Aquatic Science, Vol 16, No:1-2: 175-182 (English abstract).

Serdar, S., Hindioğlu(Lök), A., (1999) Resting egg formation of rotifer (Brachionus plicatilis Müller, 1786) at different salinities. Journal of Fisheries and Aquatic Science, Vol 16, No:3-4: 279-287 (English abstract).

Serdar, S., Lök, A., (2002) Effects of temperature on resting egg formation in the rotifer (Brachionus plicatlis, Müller, 1786) culture. Journal of Fisheries and Aquatic Science, Vol:19, No:1-2:13-17 (English abstract).

http://www.glerl.noaa.gov/seagrant/GLWL/Zooplankton/Rotifers/Pages/Brachionidae.html http://www.microscopies.com/DOSSIERS/Magazine/Articles/M%20Verolet-CLE/14-1-famille%20Asplanchnidae1/famille

%20Asplanchnidae1.htm http://rotifera.lifedesks.org/node/213http://biology.mcgill.ca/faculty/fussmann/rotifers.htmlhttp://www.oysterhatchery.com/algal-production.shtml

http://pubs.ext.vt.edu/600/600-105/600-105.html

References