ABEYGUNAWARDANA, E.A.W.R.2021-03-242021-03-242013UWU/AQT/09/0001http://www.erepo.lib.uwu.ac.lk/bitstream/handle/123456789/6244/UWULD%20AQT%2009%200001-08052019102728.pdf?sequence=1&isAllowed=yThe effect of different protein and lipid levels for growth of farmed catfish, Pangasius sutchi fry were studied for six experimental diets using a 3 x 2 factorial design with triplicates. Groups of 12 fish per tank, with initial mean weights of 1.07 + 0.18 g were fed with six test diets comprising combination of three crude protein levels (25%, 30%, 35%) and two lipid levels (6%, 10%). Feeds were incorporated with an inert marker (Chromic oxide) to measure the digestibility .The fish were fed until satiety twice a day for 7 weeks by manually. Feed Conversion Ratio (FCR), Specific Growth Rate (SGR) and Condition Factor (K) were calculated for each diet. FCR and SGR were significant among the test diets while K was not significantly differ (p>0.05) among the test diets. The highest SGR and lowest FCR was recorded for the diet contain 35% protein and 10% lipid and it was not significant (p>0.05) from the diet that contained protein 35% lipid 6%. The lowest SGR and highest FCR were recorded for the diet contained protein 25% lipid 10% also. The digestibility was also not significantly different among all the test diets. Results of the experiment indicate that the use of combination 35% protein and 6% lipid for the diet of Pangasius sutchi most effective protein and lipid level for the growth performance. Key words — Digestibility, Feed conversion ratio, Specific growth rate, AquacultureenAquatic Resources Technology Degree Programme ( AQT)Thesis