Małgorzata Bonisławska, Adam Tański, Arkadiusz Nędzarek and Agnieszka Tórz
The study examined the development of pike (Esox lucius L.) roe in water containing variously concentrated coagulants PIX®113 and PAX®18, which are increasingly being used in Poland as a method of lake reclamation. The genital products came from spawners caught from a natural water body (Lake Przybiernów). The eggs were incubated in water taken from the same lake, and subjected to the process of phosphorus and iron precipitation with coagulants. Based on the results, it was found that the coagulants used in the experiment inhibit the embryogenesis of pike by the formation of aggregates falling to the bottom, reducing the percentage of live embryos and affecting the size and malformation of the hatching larvae.
Adam Tański, Małgorzata Bonisławska, Agnieszka Tórz, Krzysztof Formicki, Arkadiusz Nędzarek, Arkadiusz Drost and Agnieszka Rybczyk
The study focused on the effect of iron and aluminium coagulants (PIX®113, PAX®18) commonly used for purification of open waters on key stages of embryonic development of pike (Esox lucius L.). Fertilized pike roe was incubated in lake water and in water with the admixture of coagulants, applied in the concentration of 50.0 mg dm-3 at selected stages of embryogenesis: blastopore closure, inoculation, and the hatching of larvae. In the course of the experiment, live embryos were observed and total lengths of the larvae were measured. Simultaneously, selected hydrochemical indicators were gauged. It was discovered that coagulants had the strongest effect at the first stage of embryogenesis (the end of the process of gastrulation). At that stage the survival rate of embryos was the lowest (73.5- 75.0%) and the percentage of deformities in the hatched larvae was the highest (9.7-10.0%).