The Effect of Aluminium and Iron-Based Coagulants U sed for Lake Recultivation on the Sperm Motility and Fertil isation of the Pike ( Esox lucius L.)

Abstract

The objective of the research was to test the effec t of iron and aluminium coagulants commonly used for lake re-cultivation, on the pike sperm motility and fertilisation. The coagulants caused changes in the analyzed hydrochem ical parameters of the water such as: Fe, Mg 2+ , TSS, SO 4 2- and Cl - . Selected parameters of sperm motility: MOT, VCL, VSL, VAP, LIN were estimated using CASA. The sperm motility at the moment of activation was the highest in the control sample. W ith increasing the time of exposure the proportion of sperm motility in the analyzed semen decreased. In the samples with coagulants the values of MOT, VCL and VSL were smal ler than in the control sample (statistically significant differences between the control and the samples with PIX and PAX were recorded in the 25 th -30 th second after activation). The percentage of fertil ised eggs was the greatest in the control sample and in the PAX®18 sample (73.11 and 70.42%, respectively), whereas in the PIX®113 it was less t han that (54.88%). The shortest larvae were those in the sample with coagulant PIX®113. In the samples with PIX®113 and PAX®18 the survivorship of embryos compared to the control sample was the smallest (43.10 and 51.61%, respectively and control 67.60%) and the proportion of malformed larvae was the highest (34.82 and 24.52%, respectiv ely and control 15.17%). Keywords: Coagulants, Fertilisation, Lake, Pike, Sperm moti