The importance of Calla palustris L. in the Achiri outbreak of Haff disease

The aim of the study is to determine the role of Calla palustris Linnaeus, 1753 in the occurrence of the Achiri outbreak of Haff disease. Hydrobotanical samples were collected from water bodies, in the coastal zone, including in places where Calla palustris grows. Plant samples were collected at 12 stations (6 stations on Lakes Ishmenevskoye and Andreyevskoye) in the spring and summer, chopped with scissors, homogenized with a blender and introduced daily into aquariums, where one part of detritus was introduced daily, gradually increasing its concentration. After 15 days of the experiment after the introduction of 1125 g of detritus, the fish were fed to laboratory animals. A biological test on mice (n = 5) was carried out for 17 days. On the lakes Andreyevskoye and Ishmenevskoye, where the Haff disease has been recorded, the marsh calla is quite common, but does not form monospecific thickets. When conducting a biological test on mice that were fed fish containing marsh calla detritus, the mice showed signs that directly and indirectly indicated Haff disease in the form of timidity, hypodynamia, purulent conjunctivitis, "triangle" and "frog" poses. The mortality rate among the experimental animals was 100 %. Pathomorphological changes coincided with those in Haff disease and were characterized by changes in the liver, kidneys and spleen. The experimental animals did not show changes in the skeletal muscles, which is not typical for Haff disease. The identity of the clinical picture in experimental animals that consumed fish that participated in the biological test with the detritus of the marsh calla indicates the importance of this plant in the formation of the toxin of the Haff disease.