Page 14 - 240 introduction to fisheries and aquaculture tecnologies-azam
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Introduction to Fisheries and Aquaculture Technologies
OS. Impact of environment No adverse effect on environment.
06. Expected outcome a. Increase fish production through ensuring more seed
production by induced breeding.
b. Create employment opportunities.
07. Recommendations a. Mature brood fish has to be chosen for pituitary gland
collection.
b. Pituitary gland should be collected before fish become
spoilage.
4. Polyculture of Carps
01. Contact division/person/unit Freshwater Station, Bangladesh Fisheries Research
Institute, Mymensingh
02. Location of application Perennial ponds all over the country.
03. Key characteristics of the a. To utilize the entire food web in the pond ecosystem
technology through polyculture of carp species of different
feeding habit.
b. To utilize locally available agricultural by-products
and residues as fish feed.
c. To obtain higher fish production.
04. Production guidelines
Pond preparation a. Pond selection-perennial pond preferably with an area
of 0.2 to 0.6 ha and average water depth of I.S to 2.S m.
b. Dewatering and drying of pond, if not possible,
predatory fish and insects should be eradicated
completely before stocking, using rotenone @ 60-80
g/dec.(water depth 2-3ft).Liming @ 2S0 to 300 kg/ha.
c. Manuring/fertilization - cowdung @ 2 to 3 tons/ha S-
7 days after liming. Urea and triple super phosphate
(TSP) @ SOkg/ha in I: 1 ratio one week before
stocking.
Stocking a. Density @ SOOO to 6000 fingerlings (J0-1Scm)/ha.
b. Species ratio @ silver carp tHypophthalmichthys
molitrix) 30%, catla (Catla catla) 10%, rohu (Labeo
rohita) 20%, mrigal (Cirrhinus mrigala) 2S%, grass
carp (Ctenopharyngodon idella) 10% and common
carp (Cyprinus carpio) 'S%. In addition 2000
fingerlings/ha of rajpunti.
Feeding Supplementary feed with a mixture of 7S% rice bran
and 2S% mustard oilcake @ of 2 to 3% body weight.
Soft grass may be supplied for grass carp. Rice bran
@ S to 6% body weight of fish.
Fertilization Urea: TSP = 1 : 1 @ 100 kg/ha/month and organic
manure (eg. cowdung) @ 2000 kg/ha/month. Each
fertilizer should be used in every alternate weeks.
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