Influence of lysine on weight gain of carp fry (Cyprinus carpio) in cage and fishpond farming

The paper shows research results on the effect of the synthetic amino acid lysine added to feed mixtures on breeding results for carp fry bred in cage s and fishponds. The experiments in cages and fishponds were carried out in three replications. Three different types of feed mixtures were tested: po sitive control feed mixture (33.1% protein and 1.8% lysine), experimental f eed mixture (28% protein and 1.3% lysine) and negative control feed mixture (27.96% protein and 1.3% lysine). For cage breeding, identical weight gain (positive control 22.8 g.ind(-1), experimental group 22.7 g.ind(-1)) and f eeding coefficient results (positive control 2.10, experimental group 2.11) were found in the positive control and the experimental group. Significant ly lower weight gain results (17.9 g.ind(-1)) and feeding coefficient (2.68 ) were found in the negative control group. Other breeding parameters (SGR, PER) were significantly better in the positive control and the experimenta l groups in comparison with the negative control group. For fishpond farmin g, significantly better results for weight gain, feeding coefficient, SGR a nd PER values were determined for the control and experimental groups in co mparison with the negative control (P < 0.01). There were no statistically significant differences between positive control and experimental groups (P > 0.05).