Biometric analysis of food products of hybrid hypoophthalmichthys (Hypophthalmichthys spp.) to determine their nutritional value and use in the food industry

Anotace: This scientific work describes research, the purpose of which was to study the spectrum of nutrition and the composition of the food lump, as studies aimed at assessing specific weight (%) of essential nutrients (glycogen, proteins, and lipids) in particular organs and tissues of different size and mass groups of the hybrid of Silver carp and Bighead carp in ponds and reservoirs in different periods of the year. In 2018, and 2019, the juveniles of the hybrid of Silver carp and Bighead carp in ponds and reservoirs mainly consumed phytoplankton organisms (from 30 to 90% by mass), among which green, diatom, and euglena algae predominated by mass in the food group. Zooplankton occupied an insignificant place in fish nutrition (up to 5%), even though its quantity and biomass were sufficient in reservoirs. The hybrid of Silver carp and Bighead carp does not hurt zooplankton communities, so it can be included in the stocking volume of Silver carp. The feeding spectrum and rations of different groups of Silver carp and Bighead carp in ponds and reservoirs had a well-defined seasonal character related to the composition of feed objects. In all size and mass groups of the hybrid of silver and bighead carp from ponds and reservoirs in 2018, and 2019, mostly satisfactory values of general metabolism indicators were found – glycogen, proteins, and lipids in the liver, gills, and muscles of fish. The difference found in the availability of essential nutrients in the body of the studied fish indicates a change in the intensity and direction of their metabolic processes.