Premium
Mutual influence of protein and lipid feed content on European catfish ( Silurus glanis ) growth
Author(s) -
HasSchön E.,
Bogut I.,
Kralik D.,
Vuković B.
Publication year - 2004
Publication title -
journal of applied ichthyology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.392
H-Index - 62
eISSN - 1439-0426
pISSN - 0175-8659
DOI - 10.1046/j.1439-0426.2003.00521.x
Subject(s) - catfish , biology , food science , fish oil , soybean oil , protein efficiency ratio , fish <actinopterygii> , zoology , feed conversion ratio , fishery , body weight , endocrinology
Summary We wished to determine protein and lipid content in pelleted raw fish food, necessary for optimal growth of European catfish ( Silurus glanis ). Experiments were set up in 20 cages, each holding 30 young catfish. Fishes in each cage received a different food combination over a 98‐day period at favourable physical and chemical water conditions. Food protein content varied between 37.5 and 45%, while lipid content, added in the form of soybean oil, varied between 3 and 11%. The oil contained an adequate ω ‐fatty acids concentration, necessary for fish growth. The main growth indicators determined at the end of experiment were total body gain, specific growth rate and feed conversion ratio. There was a high statistical difference among the experimental groups receiving variable food combinations for each growth parameter (P < 0.001). Both protein and lipid food content affected growth parameters, but in a different manner. Further analysis – percentage of change depending on lipid to protein ratio and bivariate surface analysis – allowed us to recognize the most economical combination: 39.5% protein + 9% lipid content. The addition of 9% soybean oil to the fish food reduces the necessary protein concentration by 5.5%, with resulting identical catfish growth effects.