HISTOPATHOLOGICAL AND PARASITOLOGICAL ANALYSIS OF Barbus balcanicus Kotlík, Tsigenopoulos, Ráb & Berrebi, 2002 TISSUES AS A BIOINDICATOR OF MILJACKA RIVER

Abstract

Water ecosystem pollution causes stress in fish species and leads to diseases as a consequence of interaction with opportunistic pathogens. Parasitic species pose a particular threat to fish health, being transmitted from one fish to another through direct and/or indirect means. This research conducted a parasitological analysis of the bioindicator species Barbus balcanicus. Histological analysis was performed to detect the relationship with parasitic infections, as well as the correlation between water bacteriological parameters and inflammatory processes in fish tissues. Sampling was carried out in July 2021 at two locations in the Miljacka River. Analysis of the tissue samples from the individuals detected the presence of parasites from the groups Protozoa and Trematoda, which were identified up to the level of genus or species using relevant keys and literature. Alongside ichthyoparasitological research, an analysis of physicochemical water icrobiological analysis was conducted, with results indicating pollution of the Miljacka River and favorable conditions for parasite development. Histological analysis confirmed the presence of pathological lesions in the gill and liver tissues of individuals, linked to parasitic infections and the presence of pathogenic microorganisms. Various pollutants in water ecosystems contribute to the presence of parasites and histopathological changes in fish species, while parasitic infections and tissue changes indicate poor ecological status and contamination of surface waters.