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A method for the identification and determination of ionophorous coccidiostatics such as monensin, salinomycin, narasin and lasalocid in feedingstuffs has been described. The method is based on the reaction of these compounds with an alcoholic vanillin solution. Separation and identification of the ionophores by means of the thin layer chromatography permits to detect monensin, salinomycin and narasin in the amounts of 5 mg/kg and lasalocid by 10 mg/kg feedingstuffs. Quantitative determinations are performed by the colorimetric method at 518 nm. The method makes possible to detect monensin, salinomycin and narasin at the content of 1.0 mg/kg feedingstuffs. However, this method is not applicable for lasalocid.
In the period 1993-1996, the Maltański Reservoir was found to host 233 phytoplankton taxa, belonging to 9 taxonomic classes. The most numerous were cyanobacteria. After regression of the Cyanobacteria-induced water blooming in the spring, chrysophytes, cryptophytes, green algae or diatoms were dominant. The remaining taxonomic groups were clearly less numerous. Changes in the number of a cells and of individual organisms and changes in the phytoplankton biomass were monitored in seasonal cycles. The shares of individual size fractions, i. e., of microplankton (>60 μm) and nanoplankton (2-60 μm) in the total numerical force and biomass of phytoplankton were estimated. Considering the size structure of phytoplankton organisms, nanoplankton comprised 50-100%, particularly in the period between November, 1994 and April, 1995, as well as in the early summer (May, June). Microplankton prevailed in total numbers of organisms between April and October, in particular. High correlation were noted between the number of organisms, number of cells and biomass of phytoplankton on one hand and the physico-chemical parameters of water such as transparency, temperature, pH, BOD₅ index, conductivity and total phosphorus on the other. This pointed to the role played by these parameters in the development of algae. On the other hand, dissolved phosphates, nitrite and ammonium nitrogen exerted no limiting effects on the development of phytoplankton.
Our study was undertaken to perform comparative analysis of five lakes in the area of the Promno Landscape Park: Brzostek, Dębiniec, Dobre, Kazanie, and Wójtostwo. The physico-chemical parameters of the lakes, including water temperature, chlorophyll-a, dry mass of seston, dissolved oxygen, pH, conductivity, visibility, nitrogen concentrations (ammonium, nitrate, and nitrite), and phosphorus (water-dissolved phosphates and total phosphorus) were measured. The species composition, abundance, and biomass of phytoplanktonic organisms were studied in five lakes. Water samples were collected in summer 2007. The analysis exhibited extensive variability, both in respect to the number of taxa and phytoplankton abundance. The most numerous group of algae, in respect to the number of taxa, were green algae.
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