Effect of dietary protein level on the growth of Deccan mahseer fry Tor khudree Sykes

Four feeds having different protein levels were separately tested on Tor khudree fry having an average length of 23.5 mm and weight 55 mg. The best average growth of 15.66 mg and 0.456 mm/day was obtained with Feed IV which comprised rice bran, ground nut oil cake, Acetes, wheat flour and mineral mix at the ratio of 1:1:1:0.7143:0.01428. These constitute 35.29% of proteins. The Feed II which comprised R.B + G.O.C. + prawn shell + wheat flour and mineral mix at a ratio of 1:1:1:0.7143:0.01428 contained 32.61% crude proteins. It provided a growth rate of 14.83 mg and 0.440 mm per day. The conversion rates were 38.258 and 37.776 for feeds IV and II respectively. Since Feed II is cheaper than Feed IV and provides almost equal growth rate, it can be used in the nurseries for intensive rearing of T. khudree fry.

Experimental formulation of an anti fouling paint with tributyl tin oxide as toxic pigment

Results of the experimental formulation of an antifouling paint incorporating TBTO as toxic pigment are presented in this paper. Of the various resins tested, namely, phenolic, cashew nut shell liquid (CNSL), epoxy linseed oil with rosin and limed rosin, the paint composition with limed rosin gave the critical leaching rate of TBTO. Acid alkali test showed dissolution of matrix and visible migration of toxin to the surface. Accelerated corrosion tests had not recorded any signs of corrosion in panels painted with or without barrier coat. Raft exposure studies indicated that the new formulation could resist fouling accumulation on painted panels for 9 months.