Protein Requirement Protein and Amino Acid Requirement

7 high as 3 mg L -1 . Optimal water temperature for growth ranges from 28°-30°C, and pH 5-9 Stickney 1993. Concentration of ammonia must remain less than 1.5 mg L -1 Harimurti et al. 1995.

2.2.2 Protein and Amino Acid Requirement

Fish need feed with nutritional component which is appropriate to the size and the species. The basic diet for fish must contain sufficient levels of high quality protein and energy as well as balance essential fatty acids, vitamins and minerals. Information about nutrient requirement of patin remains scarce, thus information available for channel catfish are often used.

2.2.2.1 Protein Requirement

Young fish require higher protein level compared to larger fish as their metabolic and growth rate are higher Stickney Lovell 1977. Generally, catfish species requires protein level ranging 35-45 in its diet NRC 1993. Gaylord and Gatlin 2001 reported that the growth rate of channel catfish increased when they fed on high protein 37 and high energy diets 3.6 kcal DEg. Protein requirements of channel catfish fry are higher than those of fingerling or adult fish. Protein levels of 52 and 40 are required for catfish fry and fingerling weighing 0.02 g and 20 g, respectively Robinson et al. 1994. Based on weight gain, FCR Food Conversion Ratio, PER Protein Efficiency Ratio and ANPU Apparent Net Protein Utilization 11 , Hung 1999 estimates the dietary protein requirement for Pangasius bocourti and P. hypophthalmus as 16 and 17 g CP kg -1 fish day -1 , with an energy supply of 1150 and 900 kJ GE kg -1 fish day -1 . For P. bocourti, P. djambal, and P. hypophthalmus, Hung et al. 2004 obtained 90 of the maximal specific growth rate for energy with a energy supply of 1212, 1084, and 952 kJ GE kg -1 day -1 , respectively with a nearly 20 MJ per kg diet. In a study comparing utilization of carbohydrates in P. bocourti and P. hypophthalmus, growth rate was not affected by gross energy supply as high as 833 kJ GE kg -1 day -1 corresponding to a dietary energy content of 20 MJ kg -1 Hung et al. 2003. For all these studies, feeding rates leading to 1 Similar to the protein retention parameter used in this document 8 higher growth range from 30 to 50 g diet kg -1 day -1 with a dietary protein to energy PE ratio from 16 to 20 mg CP kJ -1 . Protein requirement for other catfishes is given in Table 1. Table 1. Nutrient requirement of catfishes Species Requirement Reference Protein g kg -1 PE Ratio mg protein kJ -1 GE Fat g kg -1 Clarias anguillaris 400 Madu and Tsumba 1989 C. batrachus 395 31 Mollah and Hussain 1990 310 24.2-25.8 Rabegnatar and Hidayat 1992 C. gariepinus 400 Degani et al. 1989 500 24 Henken et al. 1986 430 20.5 82.3 Ali and Jauncey 2005 C. isheriensis 370 22 Fagbenro 1992 Heterobranchus bidorsalis 400 25 Kerdcheun 1992 H. longifilis 425 26 Fagbenro et al. 1992 Heteropneustes fossilis 280-350 Akand et al. 1989 Ictalurus punctatus 320 25 NRC 1993 Satoh et al. 1989 Mystus nemurus 420 27 Khan et al. 1993 291 20,76 63.5 Kurnia 2002 350 29.36 129.1 Suryanti et al. 2003 Pangasius sutchi 250 Chuapoehuk and Pothissong 1985 P. djambal 677 32.55 Suhenda et al. 2004 352 31.75 62.5 Suhenda et al. 2003 P. hypophthalmus 354 28.24 40 Subamia et al. 2003 296 26.46 77 Syamsunarno 2008 mg protein kJDE

2.2.2.2 Amino Acid Requirement