Tryptophan requirement of juvenile Asian sea bass Lates calcarifer

Abstract

The dietary requirement of tryptophan for juvenile Asian sea bass (Lates calcarifer Bloch) was studied. The juveniles (mean initial weight, 5.30 ± 0.06 g) were given semi-purified test diets containing fish meal, gelatin, squid meal, and crystalline amino acids, for 12 weeks. Each set of isonitrogenous and isocaloric test diets contained graded levels of tryptophan. Fish (15 per tank) were reared in 250-L fiberglass tanks provided with continuous flow-through sea water at 26°C and salinity of 28 p.p.t. Fish were fed twice daily at a feeding rate of 8% of the body weight day )1 for the first 4 weeks and at 3.5-2.5% of the body weight day )1 from 5 to 12 weeks. The experiment was in a completely randomized design with two replicates per treatment. Mean percentage weight gains and feed efficiency ratios were significantly different in fish fed varying tryptophan levels. Survival was 100% in all treatments. On the basis of breakpoint analysis of the growth response, the dietary tryptophan requirement of juvenile Asian sea bass is 0.41% of the dietary protein. This information will be useful in further refinement of practical feed formulations for the Asian sea bass.

Dietary amino acid l-tryptophan requirement of fingerling Indian catfish, Heteropneustes fossilis (Bloch), estimated by growth and haemato-biochemical parameters

“…The higher HSI values along with the poor growth and feed conversion efficiency at marginal levels of dietary tryptophan might be due to the unstable liver function at these tryptophan-deficient diets. Kim et al (1987) reported that when tryptophan is limiting or deficient, more of the other amino acids will be oxidized, resulting in more ammoniogenesis and lower nitrogen retention, while an increase in HSI values below the methionine and tryptophan requirements in fish has also been reported in Asian sea bass (Coloso et al 1999(Coloso et al , 2004. Berge et al (2002) reported that diet containing marginal arginine and lysine resulted poor growth, FCR, PER and high HSI values.…”

“…After lysine and methionine, tryptophan is one of the most limiting amino acid in plants protein used for fish feed such as corn meal, wheat grain meal and mung bean meal (Kim and Lall 2000;Coloso et al 2004). Tryptophan along with water soluble vitamin niacin plays an important role in the brain as a precursor of the neurotransmitter serotonin, which has a major effect on the feeding behaviour of animals among its many functions (Blundell and Latham 1978;Tackman et al 1990;Mullen and Martin 1992;Coloso et al 2004). Tryptophan along with niacin is also involved in protein and lipid metabolism in fish (Ahmed 2010) and also required for the synthesis of insulin-like growth factor-1 (IGF-1), which is involved in improving the growth rate of fishes (Perez-Sanchez and Le Bail 1999;Dyer et al 2004).…”

“…The dietary tryptophan requirement has been worked out for a limited number of cultured fish species such as sockeye salmon Oncorhynchus nerka (Halver 1965), channel catfish (Wilson et al 1978;Ng et al 1997), rainbow trout (Poston and Rumsey 1983;Walton et al 1986;Kim et al 1987), gilthead sea bream Sparus aurata (Luquet and Sabaut 1974;Kaushik 1998), milk fish (Coloso et al 1992), Indian major carp Labeo rohita (Murthy and Varghese 1997), African catfish Clarias gariepinus (Fagbenro and Nwanna 1999), Asian sea bass Lates calcarifer (Coloso et al 2004), hybrid striped bass Morone chrysops x M. saxatilis (Gaylord et al 2005), and an other Indian major carp, mrigal (Ahmed and Khan 2005).…”

“…Amino acids are required by all fish species, and tryptophan is of particular concern (Ahmed and Khan (2005). After lysine and methionine, tryptophan is one of the most limiting amino acid in plants protein used for fish feed such as corn meal, wheat grain meal and mung bean meal (Kim and Lall 2000;Coloso et al 2004). Tryptophan along with water soluble vitamin niacin plays an important role in the brain as a precursor of the neurotransmitter serotonin, which has a major effect on the feeding behaviour of animals among its many functions (Blundell and Latham 1978;Tackman et al 1990;Mullen and Martin 1992;Coloso et al 2004).…”

Redefining the requirement for total sulfur amino acids in the diet of barramundi (Lates calcarifer) including assessment of the cystine replacement value

“…Studies focusing on individual amino acid requirements of barramundi (Lates calcarifer) are limited, with estimates made for only four of the ten amino acids known to be essential to fish (Methionine/TSAA, Coloso et al (1999); Lysine and Arginine, MurilloGurrea et al (2001) and Tryptophan, Coloso et al (2004)). …”