| Abstract | Gnojidba ribnjaka važna je za osiguravanje kvalitetne prirodne hrane riba u slatkovodnoj akvakulturi. Kvalitetna prirodna hrana u ribnjaku izvor je boljeg prirasta mase i dužine riba. Određeni stadiji u proizvodnji šaranskog mlađa, ličinke i mjesečnjaci za pravilan rast i razvoj trebaju prisutnost prirodne hrane u obroku. U proljeće 2021. g. na Ribnjaku 1961., Siščani provodila se gnojidba organskim kokošjim gnojivom radi ostvarivanja prirodne hrane za nasad ličinki šarana. Gnojidba se provodila na 3 mladičnjaka (E-1, B-2, B-3) u sličnom omjeru obzirom na njihovu veličinu (B-2, 550 kg/ha; B-3, 450 kg/ha; E-1, 430 kg/ha). Nasad ličinki iznosio je 500 000 kom/ha. Određivanja kvalitativnog i kvantitativnog sastava planktonskih zajednica i praćenje prirasta jednomjesečnih riba izvodilo se od 27.05. do 02.07.2021. godine. Na ribi se uz pomoć metra i vage mjerila totalna dužina (TL) odnosno masa riba (W), a kod planktona njihov kvantitativno-kvalitativni sastav. Na mladičnjaku B-2 najviše se razvio fitoplankton Cyanophita, zatim Chlorophyceae, Diatomeae, Rhodophyta i Pyrrophyceae, na B-3 najviše se razvila skupina Chlorophyceae, zatim Cyanophita, Diatomeae, Rhodophyta , Pyrrophyta a na E-1 najviše se razvila Cyanophyta, zatim Chlorophyceae, Diatomeae i Euglenophyta. Od zooplanktona na B-2 najviše se razvila skupina Rotatoria, zatim Cladocera i Copepoda, na B-3 najviše se razvila Cladocera, zatim Copepoda i najmanje Rotatoria, dok se na E-1 najviše razvila skupina Copepoda, zatim Rotatoria, a najmanje Cladocera. Preživljavanje ličinaka do dobi od 40 dana iznosila je 20%, a ukupni W i TL jednomjesečnih riba na kraju istraživanja su iznosile za B-2, (W=26,9 0,36 g , TL=11,36 0,65 cm); B-3 (W= 20,0 0,50 g, TL= 10,3 0,64 cm); E-1 (W= 16,7 0,35 g, TL= 9,8 0,83 cm). |
| Abstract (english) | Pond fertilization is important to ensure the quality of natural food for fish in freshwater aquaculture. High quality natural food in the pond is a source of better weight gain and length of fish. Certain stages in the production of carp fry, larvae and month-old fish require natural food in the diet to grow and develop properly. In the spring of 2021, in Ribnjak 1961, Siščani, a fertilization with organic poultry manure was carried out to obtain natural food for carp larvae. Fertilization was applied evenly to 3 fish ponds (E-1, B-2, B-3) in a similar proportion in relation to their size (B-2, 550 kg/ha; B.-3 450 kg/ha; E-1 430 kg/ha). Larval planting was 500 000 pieces/ha. Determination of qualitative and quantitative composition of planktonic communities and monitoring of juvenile fish was conducted from 27/05 to 02/07/2021. The average total length (TL) or average weight of the fish (W) was measured using gauges and scales. Quantitative and qualitative composition was tracked in the plankton communities. At B-2, the most developed phytoplankton was Cyanophita, followed by Chlorophyceae, Diatomeae, Rhodophyta, and Pyrrophyceae; at B-3, the most developed group is Chlorophyceae, followed by Cyanophita, Diatomeae, Rhodophyta, Pyrrophyceae; at E-1, the most developed is Cyanophita, followed by Chlorophyceae, Diatomeae, and Euglenophyta. For zooplankton on B-2, the most developed group was Rotatoria, followed by Cladocera and Copepoda; on B-3, the most developed group was Cladocera, then Copepoda, and lastly Rotatoria; while on E-1, the most developed group was Copepoda, followed by Rotatoria and the least developed was Cladocera. The survival rate of larvae to 40 days of age was 20%, and the total weight and TL of the month-old fish at the end of the study were: B-2 (W= 26,9 0,36 g , TL= 11,36 0,65 cm), B-3 (W= 20,0 0,50 g, TL= 10,3 0,64 cm), E-1 (W= 16,7 0,35 g, TL= 9,8 0,83 cm). |
