Bacteriological evaluation of water, feed and sturgeon (Acipenser baeri Brandt) fry quality during intensive rearing in cooling water

Abstract

Skin mucus and the digestive tract contents of Siberian sturgeon (Acipenser baeri Brandt), feed and water were analyzed during intensive tank rearing. The analyses included the total number of heterotrophic bacteria on common agar at 22°C (TVC 22°C) and 37°C (TVC 37°C), the number of coliforms (TC), fecal coliforms (FC) and fecal streptococci (FS). The water was evaluated for nitrogen cycle bacteria - proteolytic, ammonifying and nitrifying bacteria of phases I and II. The lowest numbers of TVC 22°C (83600 CFU cm^-3) and TVC 37°C (7040 CFU cm-3) occurred in inflow water. The highest numbers of TVC 22°C (169200 CFU cm^-3) were present in the tanks, while TVC 37°C (7280 CFU cm^-3) were the most numerous in outflow water. Statistical analysis confirmed the influence of sturgeon rearing on the densities of these bacteria in the water. No such relationship was detected for sanitary indicator bacteria (TC, FC and FS), the numbers of which did not significantly differ between inflow or outflow water.

CORRESPONDING AUTHOR:

Izabella Zmysłowska, Uniwersytet Warmińsko-Mazurski w Olsztynie, Katedra Mikrobiologii Środowiskowej, ul. Prawocheńskiego 1, 10-957 Olsztyn-Kortowo; Tel. +48 (89) 5234532; e-mail: izabella.zmyslowska@uwm.edu.pl