February 15-18, 2009 Washington State Convention Center Seattle ...

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USE OF AQUAFLOR TO CONTROL MORTALITY DUE TO COMMON FISH DISEASES IN
FRESHWATER-REARED SALMONIDS
James D. Bowker
U. S. Fish and Wildlife Service
Aquatic Animal Drug Approval Partnership Program
4050 Bridger Canyon Road
Bozeman, MT 59715 USA
jim_bowker@fws.gov
Aquaflor ® (50% active florfenicol; Type A medicated feed, sponsor – Schering Plough Animal Health Corporation, Summit NJ)
has recently been approved for use in U. S. aquaculture for the following claims: Administer in feed at a dose of 10 mg florfenicol/kg
fish body weight for 10 consecutive days to control mortality due to (1) enteric septicemia of catfish (causative agent,
Edwardsiella ictalurid) in catfish, and (2) coldwater disease (causative agent, Flavobacterium psychrophilum) and furunculosis
(causative agent, Aeromonas salmonicida) in freshwater-reared salmonids. It’s anticipated that Aquaflor ® will be approved for
additional claims in the U. S., including use to control mortality due to F. columnare in freshwater-reared salmonids. Approvals
were the result of contributions from several public data-generating partners, including the USFWS’s Aquatic Animal Drug
Approval Partnership (AADAP) Program. The AADAP Program and their partners conducted seven controlled field effectiveness
studies in support of current and future approvals for use of Aquaflor ® to control mortality due to common fish diseases
in freshwater-reared salmonids.The field efficacy studies were conducted at hatcheries that experience recurring, somewhat
predictable outbreaks of the diseases of concern (e.g., coldwater disease, furunculosis, columnaris disease). Studies comprised
a short acclimation period, a 10-d treatment period, and a 14-d posttreatment period. Results from each study showed that mean
cumulative mortality at the end of the posttreatment period was significantly lower (P < 0.05) in treated tanks than in control
tanks and that the concentration of florfenicol in feed was within ±20% of the target concentration.
Table 1. Mean percent cumulative
mortality (MCM) in treated and control
tanks at the end of each field
effectiveness study. Note, Fur =
furunculsis; CWD = coldwater disease;
col = columnaris.
Fish
species Disease
MCM
treated
(%)
MCM
control
(%)
Coho Fur 11.1 30.3
Chinook Fur 16.2 94.4
Coho Fur 17.4 30.0
Steelhead CWD 2.0 5.0
Cutthroat CWD 75.0 94.0
Coho Col 47.3 66.7
Rainbows Col 18.4 30.4
a
P-value = 0.0551
a