Submitted to: American Society for Microbiology Branch Meeting
Publication Type: Abstract Only
Publication Acceptance Date: October 18, 2004
Publication Date: October 22, 2004
Citation: Xu, D., Klesius, P.H. 2004. Immunity of channel catfish against ichthyophthirius multifiliis. American Society for Microbiology Branch Meeting. Technical Abstract: Ichthyophthirius multifiliis (Ich) is a severe fish parasite that causes high fish mortalities and economic loss in aquaculture in the tens of million dollars annually. Chemical treatment of Ich infection is usually ineffective, costly for fish farmers, and causes public concern for food and environmental safety. Fish that recovered from Ich develop an immune response against Ich. Cutaneous antibodies were found present in the skin from fish immune to Ich. Antibodies from the Ich immune fish immobilize theronts in vitro. Invasion of theronts treated with cutaneous antibodies from immune fish was significantly lower than those from naive control fish. In vivo invasion, fewer fish were infected and the infection was less severe for fish exposed to theronts treated with anti-Ich antibodies than fish exposed to theronts treated with skin culture fluid from naive control fish. Results of this study demonstrated that immunity of channel catfish after recovery from a natural Ich infection provided protection against Ich invasion, an indication that use of vaccine is an alternative means to prevent Ich.