Open AccessDietary Protein Requirement of Juvenile Cachara Catfish, Pseudoplatystoma reticulatum
Author(s) -
Henrique Gomes Cornélio Fernando,
da Cunha Douglas Amaral,
Silveira Jennifer,
Alexandre Daniel,
Silva Carlos Peres,
Fracalossi Débora Machado
Publication year - 2014
Publication title -
journal of the world aquaculture society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.655
H-Index - 60
eISSN - 1749-7345
pISSN - 0893-8849
DOI - 10.1111/jwas.12090
Subject(s) - biology , catfish , zoology , juvenile , weight gain , protein efficiency ratio , feed conversion ratio , dry matter , food science , body weight , fish <actinopterygii> , fishery , ecology , endocrinology
Cachara, Pseudoplatystoma reticulatum , is a high commercial value carnivorous catfish in Brazil, but whose dietary protein requirement is still unknown. Aiming to determine this requirement, groups of 15 juveniles (16.08 ± 1.13 g) were fed isoenergetic diets (4600 kcal/kg gross energy) with increasing levels of crude protein (30, 35, 40, 45, 50, and 55%). After 60 d, regression analysis revealed a quadratic effect ( P < 0.05) of increasing dietary crude protein concentration on growth variables. The highest weight gain and specific growth rate as well as the best feed conversion were shown by fish fed the 50% crude‐protein diet. Similarly, protease activities were significantly higher ( P < 0.05) in fish fed 50% crude protein. However, the highest protein retention was observed in fish fed the 45% crude‐protein diet. Protein and dry matter digestibilities did not differ ( P > 0.05) for diets containing 40, 45, or 50% crude protein. Therefore, based on weight gain and at a dietary energy concentration of 4600 kcal/kg, the estimated protein requirement for juvenile cachara between 16 and 85 g is 49.25% crude protein. This is equivalent to 44.79% digestible protein and a gross energy to digestible protein ratio of 10.27 kcal/g.