EN
The aim of this work was to compare the concentration of calcium and phosphorus and Ca/P ratio in the meat, gills and liver of perch ( Perca fluviatilis L.) caught from the Lake Góreckie, Strzeszyńskie and Wędromierz (the Wielkopolska Lake District). The study involved 30 individuals of fish caught in spring. The muscles samples for analyses were taken from the large side muscle of the fish body above the lateral line. Calcium concentration was determined by atomic absorption spectrophotometer Solar 969, Unicam. Phosphorus content was analyzed with colorimetric method, by spectrophotometer Lambda 25, Perkin-Elmer (at wavelength 430 nm). The mean content of Ca in the meat of fish caught from Lake Góreckie, Strzeszyńskie and Wędromierz was 3.175, 0,516 and 2.498 g kg -1 , respectively. The significantly higher amo - unts of Ca were determined in the gills than in the meat and liver and ranged from 63.09 g kg -1 (the Lake Góreckie) to 70.24 g kg -1 (the Lake Strzeszyńskie). The mean content of P was at the same level in the meat and in the liver and ranged from 2.703 g·kg -1 to 2.812 g kg -1 . Ratio of calcium to phosphorus in the meat of fish caught from the lake Góreckie, Wędromierz and Strzeszyńskie was 1.174:1, 0.254:1 and 0,888:1, respectively.