story to find out more.
Phillip Klesius gives catfish feed that has been supplemented with vaccine at
the Aquatic Animal Health Research Unit in Auburn, Ala. Click the image for
more information about it.
New Fish Vaccines Developed by ARS
By Marty Clark
May 5, 2005
Two new fish vaccines developed by Agricultural Research Service (ARS)
scientists could save producers millions of dollars while lowering costs to
Two immersion-applied, modified live vaccines for farm-raised catfish
and other species have been developed at the ARS
Animal Health Research Unit in Auburn, Ala., and at a unit branch in
Fish are susceptible to diseases and need vaccines, but it's not easy
to inject fish. So scientists try to develop vaccines that can be administered
by immersion in water.
The two vaccines, which provide protection against Flavobacterium
columnare, have been developed by ARS, and each works differently. One
vaccine, developed by ARS microbiologist
A. Shoemaker at Auburn, is effective and has been field tested by
Intervet, Inc., Millsboro, Del. This
modified live vaccine cannot cause disease, but can persist long enough to
The other vaccine, developed by ARS molecular biologist
Bader at Auburn, does not allow a pathogen to colonize, yet allows enough
pathogen to persist for immunity to develop. F. columnare, the second
leading cause of catfish fatality, also affects many other fish species.
Two types of bacteria causing worldwide problems, Streptococcus
iniae and Streptococcus algalactiae, are being treated with killed
vaccines. Both bacteria cause streptococcal disease, but antibiotics do not
work well against them. Killed vaccines, done by injection, are not as
efficient as immersion, but research leader
H. Klesius, a microbiologist at Auburn, believes research will produce an
immersion vaccine for these Streptococcus bacteria.
Evans, an aquatic pathologist with ARS in Chestertown, has worked on
several vaccines and developed a modified live vaccine for treating
Edwardsiella tarda, another disease affecting several species. E.
tarda is both costly and a nuisance, since fish processors must shut down
and disinfect entire production lines. This fish pathogen is also a human
pathogen transmissible through skin punctures and ingestion of contaminated
about the research in the May issue of Agricultural Research
ARS is the U.S. Department of
Agriculture's chief in-house scientific research agency.