The effect of microplastics and copper metal on different hemocytes in freshwater crayfish Astacus leptodactylus

In this study, the effect of different levels of microplastics and copper, alone and in combination, on the number of total hemocytes and different hemocytes in freshwater crayfish (Astacus leptodactylus) was conducted. For this purpose, 378 crayfish with an average length of 10.64±0.76 cm and a weight of 41.12±5.15 grams were divided into 27 aquaria. The exposure period was 28 days, the number of total hemocytes and different hemocytes were checked at the end of the experiment, and hemolymph samples were taken from the crayfish. The results showed that the number of hyalinocytes in the samples exposed to 1 mg/L polyethylene microplastic and 1 mg/L copper sulfate treatment was less than in the control group. The number of granulocytes increased in the treatment of 1 mg/L of polyethylene microplastic and 1 mg/L of microplastic combined with 0.5 mg/L of copper sulfate compared to the control group, and for semi-granulocyte cells, 1 mg/L of fine plastic combined with 0.5 mg/L of copper sulfate significantly decreased and the treatment with 1 mg/L of copper sulfate also had a significant increase compared to the control group (P<0.05). Also, the number of total hemocytes in the treatments of 0.5 mg/L of microplastic combined with 1 mg/L of copper sulfate and the treatment of 1 mg/L of microplastic combined with 1 mg/L of copper sulfate decreased significantly compared to the control treatment (P<0.05), finally it can be concluded that polyethylene microplastic and copper metal alone and together can be among the polluting and damaging factors to the immune system in freshwater crayfish.