QUANTITATIVE ESSENTIAL AMINO-ACID-REQUIREMENTS FOR GROWTH OF CATLA, CATLA-CATLA (HAMILTON)

The quantitative dietary essential amino acid requirements by the fry of catla, Catla catla, were determined using a test diet containing purified ingredients. The test diets did not contain any intact protein and the only source of nitrogen was from crystalline amino acids. The quantitative requirements were elucidated by feeding a graded level of one amino acid at a time by replacement with L-alanine, isonitrogenously maintaining dietary crude protein at 40%. The feeding trials were carried out for 8 weeks under static rearing conditions. Weight gain is taken as a criterion for estimating the requirement. The break point for each requirement value was then calculated using broken line regression method. When expressed as a percentage of dietary protein, the fry of catla were found to require 4.80% arginine, 2.45% histidine, 2.35% isoleucine, 3.70% leucine, 6.23% lysine, 3.55% methionine (in the absence of cystine), 3.70% phenylalanine (with 1.0% tyrosine), 4.95% threonine, 0.95% tryptophan and 3.55% valine.