CHIRONOMUS PLUMOSUS LARVAE - A SUITABLE NUTRIENT FOR FRESHWATER FARMED FISH

Abstract

Crude protein, fat, water, ash, dry matter and essential amino and fatty acids were analyzed from freshly collected Chironomus plumosus larvae in order to evaluate their suitability as a component for farmed fish diet. The analyses were performed in intact living organisms and in the dry matter. Essential amino acids were determined by LKB 4101 automatic analyzer, while fatty acids were determined by Chronopack CP 9000 chromatograph with flame ionization detector. Crude protein content was 7.6% and 55.7% in fresh larvae and dry matter, respectively, being a value adequate for growth needs of all freshwater fish sorts and categories. Most essential amino acids in fresh larvae and dry matter are present in quantities adequate for feeding majority of omnivorous and carnivorous freshwater fish species. Crude fat content was 1.3% and 9.7% in fresh larvae and dry matter, respectively, being energetically sufficient for all warm-water living fish. The crude fat contains 26.12% saturated, 30.42% monounsaturated and 34.03% polyunsaturated fatty acids (PUFA). Among the highly unsaturated fatty acids (HUFA), the most abundant is linolenic (7.21%), followed by eicosapentanoic (4.36%), docosahexaenoic (2.49%) and docosapentaenoic (1.16%) acid. The measured quantity of ω-3 and ω-6 fatty acids (essential for omnivorous fish), as well as ω-6 to ω-3 fatty acid ratio (0.81), completely meets nutritional requirements of carp and tench.

Keywords

• Chironomus plumosus
• freshwater fish diet
• fatty acids
• amino acids
• PUFA
• MUFA