| Abstract [eng] |
Analysis of crayfish diseases, parasites and alochtonic crayfish as new diseases and parasites vector in Lithuanian waters ABSTRACT Astacus astacus, Astacus leptodactylus, Pacifastacus leniusculus and Orconectes limosus were investigated for diseases and parasites in different Lithuanian waters. Alochtonic and autochtonic crayfish species are contaminated with bacteria, viruses and fungi. Orconectes limosus and Pacifastascus leniusculus are vectors of crayfish plague and Psorospermium spp. parasite Visual diseases such as porcelain, burn sport and ectoparasites Branchiobdella were examined right after crayfish were caught together with other parameter: body length, weight and others. 2 of the crayfish Astacus astacus were infected by porcelain disease, 3.4 by burn spot disease and 91 of the crayfish had Branchiobdella spp.. Diseases, mentioned above, were not observed in Astacus leptodactylus and Pacifastacus leniusculus populations.. Estimates showed direct strong dependance between burn spot disease and PH of water pools same as abundance of the crayfish populations. Psorospermium haeckeli is fairly well widespread in Astacus astacus, Pacifastacus leniusculus and Astacus leptodactylus populations - it was found in 84, 43% and 48% of populations sampled. Relative abundance of the parasite - 7.5. Unknow fungi species found in Astacus astacus may be ascribable to the genus of Phlyctochytrium (Chytridiales, Chytridiomycetes) need more observations. Infection rate of A.astacus and A.leptodactylus by porcelain, burn spot diseases and parasite Psorospermium heackeli and Branchiobdella sp. remain the same from 1970, and it is not possible to affirm about treat of this parasite for natural populations. New diseases and parasites considering to alochtonic crayfish as vector have not been found. |
