Abstract:
Proc. Aust. Soc. Anim. Prod. 1996 Vol. 21 ARGININE REQUIREMENT OF THE BLACK TIGER PRAWN (PENAEUS MONODON) H.Z. SARACA and N.P. McMENIMAN B * Bribie Island Aquaculture Research Centre, Dept of Primary Industries, P.0. Box 2066, Bribie Island, Qld 4507 * Dept of Farm Animal Medicine and Production, The University of Queensland, St Lucia, Qld 4072 Early studies designed to investigate the essential amino acid (EAA) requirement of prawns revealed that they did not utilise crystalline amino acids effectively (Deshimaru 1982). Later it was shown that prawns could utilise crystalline amino acids providing the feed was given more frequently than twice a day (Tacon 1990). Nutritional requirements of P. monodon for several EAAs have been investigated; however, for arginine significant differences between experiments have been reported, mainly due to different methods of incorporating arginine into the diets (Chen 1995). In this study the quantitative requirement of juvenile P. monodon for arginine was determined using crystalline arginine supplementation of casein based diets. A basal diet was formulated using casein and gluten (binder) as the protein source. The EAA composition of the basal diet was very close to that of the prawn body other than for arginine which was present at 1.29%. Crude protein (CP) level was 30% which was 25% less than the recommended optimum CP level for this species. The arginine content was increased in the following 13 diets by addition of crystalline arginine. Analysed levels of arginine in diets were 1.29 (basal), 1.38, 1.5 1, 1.80,2.06,2.22,2.45, 2.65,2.90,3.09,3.25, 3.50, 3.66 and 3.89% of the dry matter. Each treatment had 2 replicates except the basal diet group (4 replicates). Each tank had 1 prawn (mean body weight 6.8&.53,=SD) and there were no mortalities during the 28 day experiment. Prawns were fed three times a day (08.00 hours, 12.00 hours and 17.00 hours) to satiation. N retention was determined using comparative slaughter procedures. Figure 1. Relationship between nitrogen retention and arginine @take in prawns Feed intake of prawns varied significantly (PcO.05) between treatments and were: 0.18 (basal diet), 0.28, 0.21, 0.36, 0.18, 0.28, 0.45, 0.51, 0.48, 0.44, 0.32, 0.35, 0.32 and 0.32 gfprawn.day, respectively. The results showed that nitrogen retention increased up to a dietary arginine level of 2.06% (Figure 1). Beyond this value nitrogen retention declined as the dietary arginine level increased (PcO.05). Reduction in nitrogen retention could possibly be attributed to a toxic effect of crystalline arginine as reported by Deshimaru (1982). Chen (1995) reported that the dietary arginine requirement for P. monodon was 2.5% (2.2% of the dietary protein). In this study, we conclude that P. monodon require 2.06% (0.82% of the dietary protein) arginine in their diet. CHEN, H.Y. (1995). The Fifth International Working Group on Crustacean Nutrition Symposium, University of Kagoshima, Japan, p. 36. DESHIMARU, 0. (1982). J. World Mariculture Sot. 2: 106-23. TACON, A.G.J. (1990). 'Standard methods for the nutrition and feeding of farmed fish and shrimp' (Argent Laboratories Press: Washington). 455