MILK FISH (MILK FISH (Chanos chanosChanos chanos))
breeding techniquebreeding technique
By Snehal kapaleBy Snehal kapale
Milk fish,Milk fish, ChanosChanos chanoschanos is cultivated extensively inis cultivated extensively in
manymany South East Asian CountriesSouth East Asian Countries like Indonesia,like Indonesia,
Philippines, Taiwan etc.Philippines, Taiwan etc.
It is aIt is a euryhalineeuryhaline fish that can tolerate not only wide rangefish that can tolerate not only wide range
of salinity varying from hyper saline to freshwater but alsoof salinity varying from hyper saline to freshwater but also
low oxygen level in water and wide ranges in temperaturelow oxygen level in water and wide ranges in temperature
varyingvarying 15ºC to 40º C.15ºC to 40º C.
Though they grow well in freshwater and brackish water,Though they grow well in freshwater and brackish water,
adults move to the sea for spawning.adults move to the sea for spawning.
TheyThey spawn offshorespawn offshore near coral reefs or small islands. Thenear coral reefs or small islands. The
eggs and larvae areeggs and larvae are pelagic.pelagic.
2-3 week old2-3 week old larvaelarvae move inshoremove inshore both by passiveboth by passive
advection and active migration.advection and active migration.
After passing throughAfter passing through shore waters and surf zoneshore waters and surf zone (where(where
tidal influence is more), they settle in mangrove swampstidal influence is more), they settle in mangrove swamps
andand coral lagoonscoral lagoons where they stay for a few months.where they stay for a few months.
Some juveniles maySome juveniles may enter freshwater lakes also.enter freshwater lakes also.
To meet the seed requirement of milk fish farms, fryTo meet the seed requirement of milk fish farms, fry
collection from natural resources was followed in allcollection from natural resources was followed in all
countries earlier.countries earlier.
But by this time, techniques have been developed to induceBut by this time, techniques have been developed to induce
breed and obtain seed of desirable quality of thisbreed and obtain seed of desirable quality of this
commercially important fish.commercially important fish.
It is long living fish, having aIt is long living fish, having a life spanlife span of more thanof more than 18 yrs18 yrs..
It is a pelagic fish exhibitingIt is a pelagic fish exhibiting schooling behaviorschooling behavior & grows& grows
Scoop net for the collection of fry and eggs in different
countries like Indonesia, Philippines, TaiwanIndonesia, Philippines, Taiwan
Reproductive biologyReproductive biology
Age at sexual maturity:- In nature and in large floating cages, milk
fish reaches sexual maturity in 3-5 yrs, but in ponds and concrete
tanks it may take 8-10 yrs.
Sex differentiation: - Males can be distinguished from females by
examining the urino-genital region. Males have two pores externally
where as females have three pores.
Breeding season: - Breeding season varies in different geographical
area. In Philippines, Taiwan and India it extends from March / April
to Aug peak in Philippines being may to June and in Taiwan and in
India being April to may.
Brood stock ManagementBrood stock Management
Brood stock raising: -
1. Either raised in the farm or can be caught from the natural habitat.
2. Collection of wild brood stock in the live condition without injury
is uncertain and hence farm rearing of juveniles or sub adults to
maturity is desirable.
3. But the long period of five years of rearing required to develop a
breeder is a major set back in expansion of milk fish culture on a
4. Inspite of these, polyculture of milk fish along with other species of
fish such as mullet, grouper and tilapia is practiced in many
Brood stock feed:-
1. As milk fish is an omnivorous fish, it feeds on a wide variety of
2. They feed mainly on algae, lab-lab (complex form of
3. Usually, before stocking the fingerlings the ponds are dried and all
predatory fauna are completely eradicated.
4. Chicken manure @ 2 tones /ha is spread on the pond bottom
5. Then inorganic fertilizer (N:P:K= 16:20:0)
@ 150 kg /ha or N.P.K.(18:46:0) @75 kg/ha is added after 2-3
6. Then urea @25kg/ha is applied to the pond. This help in speeding
up the breakdown of chicken manure within 1 week. After this
treatment lab-lab growth starts in the pond.
7. At this point water level is gradually raised by installment raised
to25-30 cm within a period of 1to1.5 months, each time raising the
water level by 3-4 cm. If the water level is suddenly increased to
30cm, lab-lab may detach from the bottom.
8. In addition to natural food, formulated feed consisting of rice bran,
wheat meal, soybean meal, and formulated eel meal was given as
food for breeders.
Brood stock conditioningBrood stock conditioning:-:-
1.1. About 2 months prior to the breeding season, breeders areAbout 2 months prior to the breeding season, breeders are
transferred to the spawning pond.transferred to the spawning pond.
2.2. If spawning pond is small and if stocking density is higher, theIf spawning pond is small and if stocking density is higher, the
fish may jump out of the pond and get injured.fish may jump out of the pond and get injured.
3.3. To prevent this, aTo prevent this, a fence of 1m height made of nylon net is fixedfence of 1m height made of nylon net is fixed
along the dyke.along the dyke.
SpawningSpawning: -: -
1.1. The brood fish can be either induced to spawn through theThe brood fish can be either induced to spawn through the
administration ofadministration of pituitary extract/ other ovulationpituitary extract/ other ovulation inducinginducing
agentsagents or they can be allowed to have spontaneous spawning inor they can be allowed to have spontaneous spawning in
the pond.the pond.
Inducing spawning through hormone therapyInducing spawning through hormone therapy: -: -
1.1. It has beenIt has been induced to spawn by the injection of partially purifiedinduced to spawn by the injection of partially purified
salmon gonadotropinsalmon gonadotropin,, mullet pituitary homogenate along withmullet pituitary homogenate along with
HCG, carp pituitary homogenate with HCG or HCG aloneHCG, carp pituitary homogenate with HCG or HCG alone
induced the milk fish to spawn.induced the milk fish to spawn.
2.2. Either theEither the hormone pelletshormone pellets were implanted intra-peritoneal or itwere implanted intra-peritoneal or it
was administrated by intramuscular injection.was administrated by intramuscular injection.
Spontaneous spawning without hormone therapySpontaneous spawning without hormone therapy :-:-
1.1. Mature milk fish also spawn spontaneously in the pond either inMature milk fish also spawn spontaneously in the pond either in firstfirst
quarter (1-7th) last quarter (24-30) and mid month (12-18) of aquarter (1-7th) last quarter (24-30) and mid month (12-18) of a lunarlunar
2.2. Usually the fish spawns after mid night though the chasing behaviorUsually the fish spawns after mid night though the chasing behavior
of males start before sunset.of males start before sunset.
3.3. During courtship, very often the dorsal fin and caudal fin are foundDuring courtship, very often the dorsal fin and caudal fin are found
projecting out of water when male chases the female.projecting out of water when male chases the female.
Incubation of the EggsIncubation of the Eggs
1.1. The fertilized eggs of milk fish areThe fertilized eggs of milk fish are spherical, translucent andspherical, translucent and
floating measuring 1.5-2.5 cm in diameterfloating measuring 1.5-2.5 cm in diameter..
2.2. It has a narrowIt has a narrow peri-vitelline spaceperi-vitelline space and there isand there is no oil globule inno oil globule in
the ooplasmthe ooplasm..
3.3. FromFrom spawning tank /floating net eggs where breeders are releasedspawning tank /floating net eggs where breeders are released
the eggs are collected before dawn by a scoop net.the eggs are collected before dawn by a scoop net.
4.4. The eggs that are cleared of the detritus are measured andThe eggs that are cleared of the detritus are measured and
transferred to well aerated tanks.transferred to well aerated tanks.
5.5. One kg (means mass of that eggs) of fertilized eggs shall contentOne kg (means mass of that eggs) of fertilized eggs shall content
about 80,0000 eggsabout 80,0000 eggs..
6.6. TheThe incubation period is 20-35 hr.incubation period is 20-35 hr. at temperatureat temperature 26-32ºC26-32ºC andand