ARS | Publication request: EFFICACY OF A MODIFIED LIVE EDWARDSIELLA ICTALURI VACCINE IN CHANNEL CATFISH AS YOUNG AS SEVEN DAYS POST HATCH

Submitted to: Aquaculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 29, 1999
Publication Date: N/A

Interpretive Summary: We developed a modified live Edwardsiella ictaluri vaccine against the number one bacterium (Edwardsiella ictaluri) which causes $40-60 million in losses to catfish producers annually in the United States. In 1997 and 1998 catfish were vaccinated by two minute immersion in the modified live Edwardsiella ictaluri RE-33 vaccine when the catfish were 7, 10, 12, 14, 16 6and 31 days old. Results showed the vaccine to be effective in catfish as young as 7 days of age by reducing mortality caused by an isolate of Edwardsiella ictaluri that could cause disease. The modified live E. ictaluri vaccine will satisfy the needs of the catfish industry because it can be used in young fish, can be administered by bath immersion and does not appear to require a booster dose.

Technical Abstract: Channel catfish (Ictalurus punctatus) were vaccinated by immersion at 7, 10, 12, 14, 16 and 31 days post hatch with modified live Edwardsiella ictaluri RE-33 vaccine in 1997 and 1998. At 20 to 21 days post vaccination the groups of vaccinates and non-vaccinates were challenged with virulent Edwardsiella ictaluri and monitored for mortality for at least 14 days following challenge. Results showed the vaccine to be efficacious in channel catfish as young as 7 days post hatch with relative percent survival ranging from 58.4 to 77.5.