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Data on the production and fish catch according to species, on the surface of the fish ponds, on the means of fish catching and on the distribution of the production and the catch in 1997 is presented. The surface area used for production of fish has decreased for 836 ha or 8.40%. The total fish amount was bigger for 477 tons, or 10,52%. The feeding coefficient is 2.6 kg decreased 35% for in comparison to the bigger compared to the previous year. The amount of the fertilizer used is bigger for 37.30%. The fry carp growing ponds make up 6.50% of the total fish pond surfaces, the young carp ponds 22.04/0, and the ponds with consumption fish 70.31%. The total amount in the carp ponds was 446 kg/ha, and in the trout ponds it was 160.8 tons/ha. The most produced fish species is the carp with 79.32%, followed by the trout with 11.50%, the herbivorous fish with 4.25%, while all the other fish species make up 4.93% of the entire production. In the structure of herbivorous fish the grass carp is leading with 69,23%, followed by the big head carp with 29.74% and the silver carp with 1.03%. Compared to the previous year the production of the carp, grass carp and tench is increased. Fish catch in open waters has decreased by 5.53% in comparison to the previous year. In the production and catch of the total freshwater fish, carp made up 75.34%, herbivorous fish made up 3.89%, trout 10.66%, sheat fish, pike perch and pike 2.70% and all other fish species 7.41%. As far as the distribution of production and catch of fish is concerned, 52,80% were sold on the market, 37.94% were used for reproduction (stocking the fish farms), mortality was 1.43%, and for personal use (sports fishing) 7.83%. The number of fisheries workers has decreased for 8.17%, and the production per worker is bigger for 22.25%, compared to the previous year. Average production per worker was 7.17% tons of fish.

Data on the production and fish catch according to species, on the surface of the fish ponds, on the means of fish catching and on the distribution of the production and the catch in 1996 is presented. The surface area used for production of fish has decreased by 1357 ha or 11.99%. The total fish amount has decreased by 1,921.00 tons or 29.76%. The feeding coefficient is 4 kg (33.33%) bigger compared to the previous year. The amount of the fertilizer used has decreased by 18.79%. The fry carp growing ponds make up 5.99% of the total fish pond surfaces, the young carp ponds 21.13%, and the ponds with consumption fish 71.53%. The total fish amount in the carp ponds was 376 kg/ha, and in the trout ponds it was 146.6 tons/ha. The most produced fish species is the carp with 82.21 %, followed by the trout with 8.57%, the herbivorous fish with 4.78%, while all the other fish species make up 4.44% of the entire production. In the structure of herbivorous fish the grass carp is leading with 64,28%, followed by the big head carp with 26.02% and the silver carp with 9.70%. Compared to the previous year the production of the trout and tench has somewhat increased, while the production of all the other species of fish has decreased. Fish catch in open waters has increased by 19.23% in comparison to the previous year. In the production and catch of the total freshwater fish, carp made up 77.46%, the herbivorous fish made up 4.32%, trout 4.32%, sheat fish, pike perch and pike 2.99% and all other fish species 7.36%. As far as the distribution of production and catch is concerned, 46.91% were sold on the market, 39.19% were used for reproduction (stocking the fish farms), mortalities were 6.23%, and for personal use (sports fishing) 7.67% was used. The number of fisheries workers has decreased by 17.75%, and the production per worker has also decreased by 26.62%, compared to the previous year. Average production per worker was 5.87 tons of fish.

An investigation was carried out in three variants of experimental fish ponds in which different technologies were applied (l - without fertilizing, feeding of carp with cereals; II - fertilizing, feeding of carp with cereals; III - without fertilizing, feeding of carp with pellets containing 20% of protein). Carp was reared under conditions of policulture with total stock density 3250 ind. ha-1 (2500 ind•ha-1 carp 250 ind•ha-1 silver carp, 250 ind•ha-1 bighead and 250 ind•ha-1 grass carp. Average weights of fishes were from 29 to 77 g. The values of some hematological and biochemical indices of carp were estimated (hematocrit, hemoglobin, MCHC, total protein and total lipids). The mean value of concentration of hemoglobin was 111,80±18,38 gl-1 (variant I); 121,60±15,86 gl-1 (variant II) and 122,00±15,61 gl-1 (variant III). Hematocrit value was 0,25±0,03 L˙L-1 0,30±0,03 L˙L-1 0,28±0,02 L˙L-1, and MCHC 0,23±0,01 L˙L-1; 0,23±0,01 L˙L-1; 0,25±0,01 L˙L-1 resp. The concentration of total protein in blood plasma of carp was 27,00±0,32 g˙L-1 (variant 1), 32,00±0,52 g˙L-1 (variant II) and 34,00±1,02 g˙L-1 (variant III). The concentration oftotallipids was 10,1O±0,29 g˙L-1,11,20±1,60 g˙L-1 and 1l,20±1,60 g˙L-1 resp. The differences between means values of these indices found in carp of different variants were significant (P>0.05) only for values of total protein (table 3) in variant III where carp was fed with protein of animal origin.