DAO prepress abstract  -  DOI: https://doi.org/10.3354/dao03197

Methodological issues affecting the study of fish parasites. III. Effect of fish preservation method

Yuriy Kvach*, Markéta Ondračková, Michal Janáč, Pavel Jurajda

*Email: yuriy.kvach@gmail.com

ABSTRACT: The aim of this study was to evaluate the influence of preservation method on the results of parasite community studies. Two host species, European perch Perca fluviatilis and European bitterling Rhodeus amarus, were examined for parasites after having been subjected to four different storage treatments: freezing, preservation in 4% formaldehyde or 70% ethanol and transportation of live (fresh) fish as a control. Preservation prior to dissection resulted in a loss of information, leading to incomplete quantitative data (all preservation treatments), qualitative data (ethanol and formaldehyde preservation) and a lowered ability to determine parasites to species level based on morphology in comparison dissection of fresh fish. Of the more abundant taxa, only crustaceans and acanthocephalans provided relatively even results between treatments. In conclusion, preservation media, such as ethanol or formaldehyde, significantly affect the ability to obtain precise parasite community data; hence, we recommend the use of freshly sacrificed fish for parasite community studies whenever possible. Alternatively, freezing may prove acceptable for evaluating parasite community taxonomic composition.