Effect of feeding common carp (Cyprinus carpio (Linnaeus, 1758)) with water fern (Azolla filiculoides (Lam.)) on its fillet quality

Purpose. Qualitative study of fillets of common carp (Cyprinus carpio L.)fed with natural powder of water fern (Azollafiliculoides) and comparison with previous studies. Methodology. The proximate composition of the samples of fish fillets was done: protein content through Kjeldahl method, lipid content was determined according to AOAC (Association of Official Analytical Chemists) official method.Sensory evaluations were done by panelists. Methods for determining water holding capacity, cooking losses and biochemical analysis were standard, accepted in the world scientific community. Findings. Dissimilarities in the composition of proteins and fats were revealed. There was a significant difference in water holding capacity, cooking losses and biochemical analysis results. According to research, the powder of water fern is recommended for use in the feeding of carp, in order to improve the quality of its fillets. Originality. In recent years, a significant amount of research has focused on the use of plants or their extracts in fish nutrition, due to the presence of antioxidants in them. Water fern powder is one of the cheapest dietary supplements, which can be used in aquaculture to reduced spending on cultivation, contemporaneously improving fish health. This is due to the fact that these aquatic plants are widespread in water bodies of most warm countries and contain many important antioxidants that can positively affect the quality of fish fillets. Practical value. Based on the data obtained, a method for improving the quality of carp fillets has been developed. So, using water fern powder in its feeding, it is possible to improve the biochemical composition, increase taste, reduce losses during cooking, and also adjust the ability to retain water. Therefore, the proposed diet is also very useful for processing aquaculture products. Keywords: water fern (Azollafiliculoides), carp (Cyprinus carpio L.), fish feeding, fish fillets quality.