No abstract

No abstract

No abstract

No abstract

The present study was conducted on two-year-old carp, reared in the production-scale conditions. The fish were kept for 62 days in cooling water and fed feeds differing in the fat content (35.9% of the energetic value of the diet) and carbohy drate content (35.6% of the energetic value of the diet). The experiment resulted in statistically significant differences in the levels of glucose, lipids, and blood lipoproteins as well as in the body composition of the fish in relation to the pre-experiment values and in relation to the ot... lier nutritional groups. INTRODUCTIONThe common carp is one of the principal fish species suitable for rearing in the con trolled conditions. In addition, it constitutes a desirable food item for consumers aware of the need for rational nutrition. These two factors combined, oblige aquaculturists to deliver the fish that is not only of good weight and condition, but is also representing desirable taste-and nutritive values. The principal concern here are the pre-determined values of proteins and lipids in the muscle tissue of the fish. As for the lipids-it is not only their content, but also the quantitative composition. According to the literature data n-3 acids present in the fish lipids play a significant role in prophylaxis of the blood-circulation disor-14 Mariola Friedrich, Katarzyna Stepanowska ders (Gertig and Przyslawski 1994) and they also can lower the frequency of breast cancer and tumors of colon (Ziemlaii.ski and Budzynska-Topolowska 1992; Budzynska-Topo lowska and Ziemlanski 1993). It has been demonstrated in a number of studies that the amounts and the composition of fish lipids are dependent on the feed components. It is not only the lipids, their quantities and the composition (Viola et al. 1981(Viola et al. , 1982 but also car bohydrates (Shimeno et al. 1981). Direct and indirect impact of the lipids and carbohydrates present in the diet on the defined metabolic pathways of the fish organism is indicated by the levels of the components of the carbohydrate-lipid transformations. Among such compo nents we can list: glucose, triacylglycerols, crude lipids, cholesterol and its LDL and HDL fractions (Friedrich 1997).The aim of the present study was to determine a possible effect of various diets, dif fering in the fat content (35.9% of the energetic value of diet) and carbohydrate content (35.6% of the energetic value of diet), on the levels of glucose, lipids, and blood lipopro teins and the body composition of the two-year-old carp. MATERIAL AND :METHODSThe experiment was conducted in summer (July-August) on 180 two-year-old carp at the Fisheries Research Station (RSD) of the Agricultural University of Szczecin, situated at the premises of the Dolna Odra power plant at Nowe Czarnowo. The fish were kept in 6 cages (2.0 x 0.75 x 0.8 m) of the usable volume of 1.0 m 3. Each cage was stocked with a total of 30 fish.The fish were randomly divided into two groups and the differentiation factor was the diet composition. Each group was tested in three repetitions. The fish...