AgriManipur - E-paolive.net

AgriManipur Volume 1, Issue 1Fertilized eggs Fertilized eggs clung to hyacinth roots C. magur hatching in well aerated FRP tank4 days old embryo of C. magur Well prepared nursery pond for C. Magur C. magur fingerlingstray. Before fertilization milt (spermatozoa)extract medium is activated by addition offresh water, sperms become active and motilityof sperms can be confirmed in microscope.Sperm preparation thus obtained willbe sufficient to fertilize the ova stripped from2 females. Sperm extract is sprinkled over theova and gametes are mixed gently using with abird feathers and allowed to 2 to 3 minutesfor fertilization and washed with fresh andclean water. After repeated washing with freshwater fertilized eggs are transferred to hatchingtrays for incubation.After transferring the fertilized eggs to theflow through incubating system, a feeble flowof water was provided to maintain good waterquality. The water temperature between 27and 28°C was maintained for developmentand hatching.Page 16Source: www.kidsfishing.orgNursery rearing:Clarias fries requires very shallow water level 2-3 ft, because at deeper water they could notswim to surface for gulping air hence died. C.magur is better suited to these shallow waters.In addition to their suitability for culture inderelict waters those catfish can also be culturedin proper well-managed shallow ponds.Pre-stocking nursery pond preparation includedthe removal of aquatic weeds andpredatory fish followed by liming and fertilizationswith organic manures and inorganicfertilizer.Recommended stocking density of Clarias is50,000/ha. However, in Thailand the stockingdensity of Clarias is very high 60-100 fingerlings/m2 (6-10 lakhs/ha). C. magur easilytrained to feed on artificial feed such as fishmeal mixed with rice bran, low grade meat, etc.Fish offal, slaughter house waste also accepted.Growth is commensurate with feeding. On anaverage the conversion rate with recommendedfeed is 1.5-2.0. Under favourble condition clariasis expected to attain weight upto 130g in sixmonths of growing period.Production potentials of C. magur inManipur have been amply assessed by a series offield demonstration in different local conditions.In monoculture production were rangingfrom 1,000kg to 7500kg ha in 4-12 months. Amixed culture demonstration of clarias withAnabas and Heteropneustes at a stocking rate of25,000/ha in a derelict swampy pond of 0.04without supplementary feeding and fertilization.From aquacultural point of view, Manipuris endowed with vast water resources thatcan be use for Clarias production.Given the fact that ngakra is a highlyvalued fish relishing among most communities inManipur, their mass and cost effective production isthe need of the hour. Large scale breeding had beenquite a big challenge among famers and scientists. Thepresent effort is a move in this direction. Mass productionwill not only help the farmers achieving goodeconomic return but will also encourage economicindependence and ensure nutritional security for thestate.