Impact of Formulated Feed on Growth Performance of the Fish Tor tor

The fry of the fish Tor tor weighing 0.347 to 0.398 g and having a length of 20 to 25 mm were collected from the Narmada river at Dhangarwada village near Hoshangabad, brought to the laboratory and acclimatized in the glass fibre tanks of 1000 litre capacity. The experiment was carried out for 270 days to evaluate the effects of different formulated feeds with different protein levels on growth and survival of fish Tor tor. In the formulated feeds fish meal was the main ingredient used along with soybean cake, ground nut oil cake, soya oil and mineral mixture.

The experiment was conducted in the glass aquaria. The fish were fed twice daily (morning and evening) at the rate of 5% of their total body weight. In control conditions, the fish was fed on commercial feed along with mosquito larvae, zooplankton and phytoplankton. About 50% of the water of each aquarium was exchanged on alternate days. Observations on fish survival, body weight and length were recorded fortnightly in each tank. Faecal material was collected and weighed after drying in a hot oven to compute the feed intake and faecal matter release. The feed and faecal samples were then analysed for proximate composition following the methods of AOAC (1980) to estimate the different nutrient contents and energy. On the basis of dry matter it was found that the moisture content of feed- I, feed-II and feed-III was 8.18%, 7.8% and 7.56% respectively and 9.14% in case of control feed. The crude protein content of feed-I, feed-II, feed-III and feed-IV was 26.25%, 32.38, 36.75 and 14.36% respectively.

Weight gain by the fry of Tor tor, fed on different diets of 35%, 45% and 50% protein levels, records an average gain in the body weight by 1.00 g, 1.165 g and 1.584 g respectively, while body length increased by 34.22 mm, 37.11 mm and 46.22 mm respectively. Significantly higher growth was observed in the diet with 50% protein than in the diets with less than 45% of protein.