not threatened perch fish in Bangladesh 6 but due to Vietnamese perch resembles with the colour of their nativerough and unplanned water management policy like counterpart which made them very much lucrative to theirrigation, over exploitation, illegal practice of capture consumer.fisheries and various ecological changes in its natural Unfortunately, there are no published literaturehabitat, this native species has now come under regarding growth and production performance of cageconsiderable pressure and considered as endangered in reared Vietnamese Koi in Bangladesh.
So, the presentsome areas 7-9. study was undertaken to bridge this information gap andConsidering the importance of this species in to develop and optimize the rearing technology ofnutritional, economics and biodiversity the cultivation of Vietnamese high yielding perch in cages through an on-Koi fish is becoming increasingly popular among the station trial which would facilitate the farmers to utilizeaquaculturists of Bangladesh. Among various production their water bodies, even the fallow one, more profitably.inputs, the choice of fast growing species with desirable The specific objective of this experiment includefindingaquaculture traits is a prerequisite for augmenting fish out of best stocking density of Vietnamese perch in cagesproduction in culture based fisheries. Natural food based with a recommended feeding regime.
Therefore, it isculture of major carp is still in practice in Bangladesh but expected that outcome of this research finding would playcarp culture could not be widely practiced in the shallow an important role to alleviate protein deficiency andand seasonal ponds. In this regard, Koi fish are an upgrading socioeconomic status of the general people ofexcellent option for growing in the shallow and seasonal Bangladesh by enhancing production of this highponds and cages as the country enjoys very suitable valuedspecies.climatic and ecological conditions for culture of warmwaterspecies 10-12. MATERIALS AND METHODSCage aquaculture has some certain advantages overother aquaculture systems that are potentially important Pond Selection and Preparation: The experiment wasin terms of uptake by rural poor and landless people. conducted at the pond of Fisheries and livestock farmGrowing fish in existing unutilized or underutilized ponds of Sher-e-Bangla Agricultural University, Dhaka,or open water bodies like rivers and floodplains, ease of Bangladesh. Experimental cages were set in thefeeding, ease of stocking and harvesting, less expense rectangular pond with an area of 1.75 acres and anassociated with treating or preventing disease, easier average depth of 2 m where rainfall was the main sourcestock management and monitoring compared with pond of water. Field trial was carried out for a period of 120 daysculture are among major beneficial point of cage culture from 23 June to 20 October, 2013.
Before starting the13. In addition to that if cages were constructed and experiment, the pond, fully exposed to prevailing sunlight,maintained properly, it could be useful for years 14. This was cleaned of aquatic vegetation. Liming (CaCO ) waspoints out that the fish could be easily cultured for done at a rate of 250 kg ha to disinfect and improveseveral cycles with same cage installment. water quality.
Because of Koi’s ability to withstand marginalizedpoor quality water and breathe atmospheric air, the fish Cage Construction and Installation: Nine cube shapedstill exists in the ecosystem of Bangladesh as a common 1m (1m×1m×1m) cages were constructed using bamboospecies 15. Considering the fact that A. testudineus has frame, black nylon net (8-10 mm mesh size) and nylonhigh growth rate, Thai Koi, a high yielding exotic variety twine. One edge of upper side of cages were kept openwas introduced in culturing pond of Bangladesh in 2002. and tied with nylon threads to facilitate variousBut due to the failure of maintaining proper hatchery management activities including supplying feed, samplingethics in the fry production phase, inbreeding has of fishes during data collection.Cages were installedresulted the receding of high yielding characteristics of keeping 15 cm of it above the surface of pond waterwhichThai Koi.
To overcome this problem, Sharnalata Agro permits each cage havinga volume of 0.85 m water. AllFisheries Ltd., Mymensingh, came forward and they cages, installed with plastic floats, were attached with abrought the brood stock of high yielding Koi from bamboo made walkway in such a way that they can adjustVietnam in 2010 and successfully produced fry on their position