Safety of florfenicol administered in feed to tilapia (Oreochromis sp.)

Toxicologic Pathology
By: , and 



The safety of Aquaflor® (50% w/w florfenicol [FFC]) incorporated in feed then administered to tilapia for 20 days (2x the recommended duration) at 0, 15, 45, or 75 mg/kg body weight/day (0, 1, 3, or 5x the recommended dose of 15 mg FFC/kg BW/d) was investigated. Mortality, behavioral change, feed consumption, body size, and gross and microscopic lesions were determined. Estimated delivered doses were >96.9% of target. Three unscheduled mortalities occurred but were considered incidental since FFC-related findings were not identified. Feed consumption was only affected during the last 10 dosing days when the 45 and 75 mg/kg groups consumed only 62.5% and 55.3% of the feed offered, respectively. There were significant, dose-dependent reductions in body size in the FFC-dose groups relative to the controls. Treatment-related histopathological findings included increased severity of lamellar epithelial hyperplasia, increased incidence of lamellar adhesions, decreased incidence of lamellar telangiectasis in the gills, increased glycogen-type and lipid-type hepatocellular vacuolation in the liver, decreased lymphocytes, increased blast cells, and increased individual cell necrosis in the anterior kidney, and tubular epithelial degeneration and mineralization in the posterior kidney. These changes are likely to be of minimal clinical relevance, given the lack of mortality or morbidity observed. This study has shown that FFC, when administered in feed to tilapia at the recommended dose (15 mg FFC/kg BW/day) for 10 days would be well tolerated.
Publication type Article
Publication Subtype Journal Article
Title Safety of florfenicol administered in feed to tilapia (Oreochromis sp.)
Series title Toxicologic Pathology
DOI 10.1177/0192623312463986
Volume 41
Issue 4
Year Published 2013
Language English
Publisher SAGE Publications
Publisher location Thousand Oaks, CA
Contributing office(s) Upper Midwest Environmental Sciences Center
Description 14 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Toxicologic Pathology
First page 639
Last page 652
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
Additional publication details