19 Volume 22 No. 3, July-September 2018 A view of rectangular FRP tanks used for tubifex culture. Tubifex in a petri dish. Production of tubifex - a new dimension of aquaculture in feeding juvenile fish R.N. Mandal l1* , S. Kar 2 , P.P. Chakrabarti 1 , D.N. Chattopadhyay 1 , B.N. Paul 1 , S. Adhikari 1 , J. Maity 2 and B.R. Pillai 3 1. Regional Research centre, Central Institute of Freshwater Aquaculture, P. O. Rahara, Kolkata 700118, India; 2. Department of Aquaculture, Vidyasagar University, Midnapore, West Bengal, India; 3. Central Institute of Freshwater Aquaculture, P.O. Kausalyaganga, Bhubaneswar 751002, India. *Corresponding author, email rnmandal1964@gmail.com With the expansion of aquaculture, a variety of alterna- tive, low cost feeds are being explored that are cheap to produce. Farmers are in need of appropriate food for spawn, particularly those of catfish species such as Ompok spp., Mystus spp, Pangasius spp., Clarias spp., and others such as climbing perch, Anabas spp. and murrel, Channa spp. The use of sludge or ‘tubifex’ worm, Tubifex tubifex, as a live food for juveniles has been long practiced in farmers’ fields. Behavioural studies have shown that catfish instinctively prefer to accept those food items which are easily detected and captured while swimming, moving or having any type of motility in the water bodies. Larvae are believed to be visual feeders adapted to capture moving prey. Also, the movement of live food is likely to stimulate larval feeding responses. Varieties of ornamental fish are commonly fed with tubifex worm. Tubifex worm is an important food item to freshwater intensive aquaculture throughout the world because of its high caloric value. Significantly, larvae of Clarius batrachus feeding upon tubifex had a higher survival rate and ten times more additional growth than those fed formulated fry feed. In such circumstances, a sincere effort is needed to develop the technique suitable to get a reliable supply of tubifex worm to be used as fish food at a large scale to sustain aquaculture, at least to catfish and ornamental fish farming. Fish farming and food Ornamental fish farming has been recognised as an important trade internationally. Culture of catfish, murrels and climbing