1. Presented by-
Priyanka santra.
Roll-10 Semester-III
ZGC-305
Department of Zoology, University of North Bengal.

2. Keeping of aquarium has emerged as the second
most popular hobby in recent years, next to
photography. The ever-increasing demand for
aquarium fishes gradually paved the way towards
global trade of ornamental fishes. India’s overall
trade presently is over Rs. 150 million.As the
ornamental fish trade is expanding. So, it is a
prerequisite to focus how the culture condition of
ornamental fishes make more efficient.

3. One of the greatest challenge in the ornamental fish
industry is to replicate the accurate natural colour of
the fish in the captive environment. Numerous
operations that have been propagated but failed to
successfully market fish due to faded colour. This
happen because in the intensive culture condition
fishes may not get the specific carotenoids which are
required to maintain their natural skin colour.

4.  There are three main groups of pigments are
responsible for the colouration of fishes, these are -
pteridines, melanins and carotenoids. Among them
pteridines, melanins are produced endogenously but
carotenoids can not synthesize enogenously so, it must
be obtained it through diet.

5. Carotenoids are 40-carbon tetraterpenoid molecules,
consisting of a series of eight, 5-carbon isoprene
residues.

6.  Carotenoids are classified according to their chemical
structure are as follows:
 carotenes and xanthophylls.
 1. Carotenes consist only of carbon and hydrogen
atoms; i.e; the hydrogen molecules of the end ring is
not substituted by any functional groups (e.g. alpha-
carotene, beta-carotene).
 2. Xanthophylls contain one or more functional group
at the end ring. Xanthophyll can be further sub divided
into two classes, depending on whether the oxygen –
containing substituent is a hydroxyl (hydroxyl-
carotenoid; e.g; lutein) or a ketone (ketocarotenoids or
oxocarotenoid;e.g., astaxanthin).

7.  Ectotherms have dermal pigment cells called
chomatophores with movable pigment-laden organelles
called chromatosomes.These are-
 Melanophores-Melanin-containing dark
chromatophore,contain either eumelanin(black) or
phaeomelanin(red) pigment.
 Erythrophores- chromatophores with reddish tint, contain
carotenoid(red /orange), in high amount and pteridine
(yellow) pigment.
 Xanthophores-Chromatophore with yellow tint,contain high
amount of pteridine and low amount of carotenoids.
 Iridophores-Light scattering chromatophore ,contain light
reflecting flat crystals.
 Leucophores-This is also light scattering chromatophore
,organelle responsible for light relection is leucosome .

8.  Carotenoids commonly occurring in fishes with their
colours are tunaxanthin (yellow), lutein (greenish-
yellow), carotene (orange), zeaxanthin (yellow-
orange), canthaxanthin (orange-red), astaxanthin (red)
etc.

9.  Carotenoids are hydrophobic compounds that are not
easily solubilised in the aqueous environment of the
gastrointestinal tract of fish; therefore, absorption ,
uptake and transport processes are associated to lipids.
 Absorption: In Intestine, carotenoid form micelle
together with bile salts, fatty acid, monoglyceride and
fat soluble vitamins.
 The micelle passively diffuse into the intestinal
mucosal cell.

10.  Uptake: In the inestinal mucosal cell the fatty acid are
converted into tryacyl glycerol(TAG) and the
carotenoid, is incoporated together with TAG. The
TAG, cholesterol eseter are coated with a layer of
protein , and form chylomicron.
 Transport: The chylomicron are then transported
through blood capillaries. When it is transported
through capillary of adipose tissue and liver the
enzyme lipoprotein lipase present in endothelial cell
hydrolyze tryacylglyceride to yield free fatty acid.
When the chylomicrons have lost about 80% of their
initial TAG content they become small enough to past
through the endothelium in the liver.

11.  Metabolism:metabolism ofcarotenoidstakeplacein
liver.Metabolismisspeciesspecific,suchas
cyprinidaefishescansynthesizeastaxanthinfrom
zeaxanthin throughmetabolicconversionwhereas
perciformesandsalmonidaecannotsynthesize
astaxanthinfromother carotenoids.Inliver
carotenoidsare associatedwithlipoproteins and
transported toblood.
 Frombloodcarotenoidassociatedwithlowdensity
lipoprotein(LDL)aretransfer tomuscle,and
carotenoid associatedwith highdensitylipoprotein
(HDL)are transfertoskin.

12. It can be divided into types-
 Synthetic carotenoids and
 Natural carotenoids.

13.  Lucanthin pink (contain 10% astaxanthin),
CAROPHYLL Red 10% (contain10 % canthaxanthin.)
are the examples of commercially used synthetic
carotenoid powder.Nearly all commercial astaxanthin
are produced synthetically.
CAROPHYLLRed(10%)
powder

14.  Synthetic processes involve petro-chemical
solvent, leading residue problem in fish.
 Synthetic carotenoid is quite expensive.
 If excess amount of synthetic carotenoid use it lead
to deteriorating effect on the environment.

15. Hematococcus pluvialis: It is a
single-cell chlorophyte species.In low
nutrient media, high light, unfavourable
environmental condition,this algae
accumulate high amount of astaxanthin.
Dunaliella salina: It is a bi-flagellate
algae, rich in beta carotene.Under
appropriate culture condition , this algae
accumulate up to 10% Beta carotene.
Arthospira maxima(spirulina): It is
a free-floating filamentous blue-green
algae.It produces zeaxanthin and
myxoxanthophyll.
All these microalgal sources of carotenoid
are commercially available in market.
Naturose powder(Hematococcus algal meal)
Spiulina pellet

16. Astaxanthin is predominant carotenoid in
crustacean by-product .
Crustacean discards are utilize as natural
astaxanthin source.
Dried shrimp meal, red crab meal , krill
meal, are commercially available as fish
feed.
However, it has cetain disadvantage, high
ash content and chitin reduce its digestibility
for fish. So, the rate of inclusion in fish diet
is severely limit.
Dried shrimp meal
Crab and krill pellet

17. Plant-based sources of carotenoids are
much cheaper than synthetic ,microalgal
based and animal based carotenoids.
Beside these plant-based sources are
easily available.
Thus researchers gives more emphasize
on plant-based sources.
But only few sources are used at present,
however, lot of experiments with different
plant based sources have been done and
many of them gives successful result.
Name of some plant-
based sources
Alfa-alfa(Medicago sativa)
Carrot(Daucus carota).
Marigold(Tagetes erecta)
flower.
West Indian Jasmine (Ixora
coccinea) flower.
China rose (Hibiscus
rosasinensis) flower.
Paprika powder.

18. Figure: Red zebra cichlid(Malyandia estherae)
The red zebra cichlid (Maylandia
estherae), is very popular among
aquarium fish ethusiasts and
common in pet stores.They are
mostly orange in colour. However,
the species displays a wide range of
colour variation of yellows, oranges,
peach, and reds has been found.
An experimental study was
conducted to observe the effect of
carotenoids in pigmentation.
Astaxanthin (from Haematococcus
pluvialis), lutein (present in corn
protein), and beta-carotene and
zeaxanthin (from spirulina) in the
skin colour of the red zebra cichlid
(Maylandia estherae).

19. The fish used in this experiment were
juvenile red zebra cichlids. The
experiment had duration of 90 days.
Fish were divided into four
experimental groups.
One group was offered the control
diet (Diet-1)that only contained basic
feed ingredients without or little
carotenoid pigments
The other three diets were prepared
using the same ingredients as the
control diet but with the addition of
carotenoid pigments from different
natural sources.
 One diet was supplemented with the
astaxanthin extracted from
Haematococcus pluvialis algae,(Diet-2)
Lutein pigment contained in corn
protein was incorporated to another
diet(Diet-3)
Zeaxanthin (from Spirulina )was
added to the fourth diet (Diet-4).
Figure: Experimental Diets,Diet-1(control),Diet-
2(Astaxanthin),Diet-3(Lutein)and Diet-4(spirulina)

20. The red zebra cichlids fed the
diet containing the carotenoid
astaxanthin developed the most
orange-red coloration. While
those fed the diet containing corn
protein concentrates (a lutein
source) became light-yellow. Fish
fed the Spirulina (a rich source of
zeaxanthin) diet became dark
yellow-orange in colour, had the
most vivid colours.The cichlids
fed the basal, control diet
(without carotenoid pigments)
had no significant changes in
their skin coloration and lacked
vivid colours .
Figure:Significant difference in Skin colouration in
red zebra cichlid, five weeks after being fed diets
containing astaxanthin(0.3%),lutein(12%) and
spirulina(12%). The control diet contain no
predominant pigment type.

21.  Vitamin A precursor
 Antioxidant activity
 Role in communication
 Role in reproduction
 Role in growth

22. Efficacy of carotenoid can only be increased when
culture conditions such as temperature, PH,
dissolved oxygen level, and other parameter
remained optimum and fishes are free from
infections. Beside this effect of carotenoid depends
on its absorption, uptake,transport ,metabolism,
and deposition .Details information about
physiological effect of carotenoids in different life
stages of various species is very important for
aquaculture industry.

23. Thank you...