Vol. 2, Issue 3, Part A (2016)

Abstract
Feeding preferences of rohu Labeo rohita (rohu) were studied in two environments i.e. substrate free and substrate based (with bamboo substrate) in a traditional fish pond. In order to determine the food selectivity under two different food environments, lvlev's Electivity Index was used. Initially it preferred zooplankton, but as the fish grows in size it shifted to both food resources i.e. plankton and periphyton in substrate based system. The fish fed a range of food items, including Chlorophyceae like Cosmarium, Closterium etc., Bacillariophyceae like Navicula, Diatoma etc., Euglenophyceae like Phacus, Euglena etc., Cyanophyceae like Aphanocapsa, Gloeocapsa. Bacillariophyceae were preferred next to Chlorophyceae. Feed selectivity study with lvlev's index revealed that fingerlings and adults of rohu differ sharply in selection of food items. When the fish was introduced into periphytic system, it prefers to consume periphyton over plankton.