A method for reducing the manifestation of genotoxic effects in the blood cells of sterlet Acipenser ruthenus under aquaculture conditions in Astrakhan Region

The effectiveness of aquaculture largely depends on the health of the farmed objects. The Volga River delta is characterized by pollution with heavy metals and petroleum hydrocarbons, which have a genotoxic effect. In this regard, the purpose of this work was to evaluate the effectiveness of experimental measures to reduce the manifestation of genotoxic effects in the blood cells of sterlet grown in cage aquaculture conditions in the Volga River delta (Astrakhan Region). These measures included sparse stocking, immunocorrection by subcutaneously administering the drug “Roncoleukin” to experimental fish and adding the probiotic drug “Vetosporin-Zh” with Bacillus subtilis to the feed. Currently, the most commonly used methods for determining the genotoxic influence of the environment are the micronucleus test and the DNA comet test. As a result, the experiment showed the success of the measures applied. The physiological state of the fish, based on blood parameters, throughout the experiment could be characterized as quite satisfactory. Some blood parameters of the fish from the experimental group at certain stages of the experiment were significantly different from the control ones. These differences are apparently associated with the adaptive reaction of fish from the control group. The response of reducing the genotoxic effect appeared after 30 days of the experiment, when in the experimental group there was a decrease in the indicators of the micronucleus test and the DNA comet method. After 50 days of the experiment, reliable data were obtained on the positive impact of the experimental measures taken on the extent of DNA damage. Despite the fact that in the control group at the end of the experiment the indicators of genotoxic influence decreased as well, a significant difference was revealed between the indicators of DNA damage in fish from the experimental and control groups. The minimum level of erythrocytes with micronuclei was noted in fish from the experimental group at the end of the experiment, while in the control group this figure exceeded the norm. The indicators of the DNA comet method were also minimal in the experimental group at the end of the experiment.