Feeding biology of near threatened small indigenous species dhela, Osteobrama cotio (Hamilton 1822)

Abstract

To get success in culture of any fish species, detail information on food and feeding
habit of that particular fishspecies is really crucial. So the present study has been performed toget
the information on the food and feeding habit of Osteobrama cotio. A total of 30 Genera of food
organisms were identified and recorded from the gut content of O. cotio, where 29 Genera
belong to phytoplankton and one belongs to zooplankton. The percentage of food composition
recorded from the gut of the fish were: Bacillariophyceae (12.90%), Chlorophyceae (63.82%),
Cyanophyceae (11.32%), Euglenophyceae (8.13%), Rhodophyceae(1.57%), Rotifera (1.43%)
and Benthos (0.83%). Chlorophyceae was the most preferred food item and benthos was the least
preferred food item of the fish. Gut fullness of the fish was the highest during May and June and
the lowest in December. The study results suggest, Osteobrama cotio is an omnivorous column
feeder with much higher preference for phytoplankton over both zooplankton and benthos. As it
is expected that the outcomes of the present study would be useful in the conservation and
management of Dhela in the open water and in the domestication in future to pave the way of the
aquaculture in captivity of this nutritionally rich threatened small fish of Bangladesh.