Polychaetes – A SUITABLE BROODSTOCK FEED FOR SHRIMP AND ORNAMENTAL FISH

Polychaetes are bristle-bearing worms, most abundant and diverse group with approximately 17,000 described species from the world. They are multi-segmented worms and assume very great significance from the point of view of ecology and aquaculture. In recent years, the demand of polychaetes has been recognized well by the aquaculture industry as it forms a potential feed for world aquaculture due to fact that the strong presence of PUFA (Poly Unsaturated Fatty Acid), which is very much essential for their egg maturation and increased spawning periodicity. True to its sense, many shrimp hatcheries located along the coasts and ornamental fish industry successfully propagate captive brood stock on a commercial scale. The reason they cite is diets for acceptable maturation performance of Penaeids which have typically relied on the inclusion of polychaetes as maturation feed. Even though various live feeds like meats of crab, squilla, squid and trash fish are available, the brooders fed on polychaetes are shown to have better results in terms of growth and maturation in shrimps and enhanced colour quality in ornamental fishes as evidenced by many researchers.

Knowing well the immense role of polychaetes as potential live feed, collection of polychaetes is being done indiscriminately along the coasts of India. The collection of polychaetes is also a form of fishing and like any other fishery there is a limit to the sustainable yield. When it exceeds the limit, it has been perceived as a non- sustainable activity with potentially detrimental effects on the natural environment. In light of these, the emergence of system for mass culturing polychaetes can provide a means to overcome the ill-effects of unsustainable collection of polychaetes worms from wild population. Though many initiatives have taken in foreign waters, in Indian context no such effort has been made hitherto. Therefore, presently an attempt was made to mass produce them in captivity so as to cater to the demand by Aquaculture industry. As an outcome of the study, the captive bred polychaetes were also experimented with shrimp brooders along with various feeding trials, the results revealed that the polychaetes fed brooders showed better results in terms of growth and maturation.