PROPHYLACTIC USE OF AKUAPROTM AND COPPER SULFATE HAS POTENTIAL TO PROTECT LARGEMOUTH BASS AGAINST COLUMNARIS DISEASE

A research trial was initiated with largemouth bass (Micropterus salmoides) to test the efficacy of AkuaPro^TM, copper sulfate or a combination of the two to prevent columnaris outbreaks, their effects on gill histopathology and whether treatments would positively impact survival rates.  Arkansas largemouth bass producers constantly combat columnaris disease, caused by Flavobacterium columnare. Columnaris disease is prevalent when largemouth bass fingerlings are stocked at high densities during the feed habituation process and when they are held in vats for extended time periods prior to being sold. AkuaPro^TM (source: Imerys, Georgia, USA), copper sulfate and the combination of the two (copper sulfate and AkuaPro^TM) were tested as a prophylactic treatment against columnaris in largemouth bass. Fish were stocked at 5 fish/ L and treated with either 1 ppt AkuaPro^TM, 3.5 ppm copper sulfate or not treated (control) once per week or using a combination of 3.5 ppm copper sulfate on day 1 and 1 ppt AkuaPro^TM on day 3. Fish samples were brought to the UAPB Lonoke Fish Disease Diagnostic Laboratory. Gills, fins, and tissues of treated and non-treated fish were examined microscopically for the presence of columnaris both before and after prophylactic treatment.  Fish from all treatments were collected for histological examination. The study is currently on-going, however, preliminary data suggests fish treated with AkuaPro^TM, copper sulfate or their combination are experiencing fewer incidences of columnaris and have higher survival rates during feed habituation process and holding periods in vats.