The state of reproductive glands of the pike Esox lucius from water bodies of the Chernobyl trail in 1999–2004

The state of the reproductive system of the pike Esox lucius, descendants of individuals exposed to X-ray irradiation due to the catastrophe at the Chernobyl Nuclear Power Plant in 1986, was studied. The material was collected in water bodies of Ukraine contaminated with radionuclides—Kiev Reservoir, the Teterev River, and Lake Glubokoe in the postcatastrophe period 1999–2004. It was shown that the total number and the extent of disturbances in the pike gonads are positively correlated with the levels of contamination of the water bodies: in the cleanest water body, the Teterev River, the proportion of fish with gonads without considerable deviations was 70%; in the Kiev Reservoir, it was 45%; no individuals with normal gonads were recorded in Lake Glubokoe. The great number of anomalies in sexual cells and gonads has led to a decrease in the reproductive capacity of the pike populations studied. A unique case was revealed of synchronous hermaphroditism in a pike from the Kiev Reservoir that belonged to the fourth generation (F₄) of fish that underwent emergency loads. Among postemergency pike generations, the maximum number of disturbances in sexual cells and gonads was recorded in F_2–4, which is possibly accounted for by the phenomenon of “prolonged mutagenesis.”