Safety of Aquaflor (Florfenicol, 50% Type A Medicated Article), Administered in Feed to Channel Catfish, Ictalurus punctatus

Abstract

Aquaflor, a feed premix containing the broad spectrum antibacterial agent florfenicol (50% w/w), is being developed for use to control enteric septicemia (ESC) in channel catfish Ictalurus punctatus caused by the gram-negative enterobacterium Edwardsiella ictaluri. The recommended dose of Aquaflor to control ESC is 10 mg/kg body weight (BW)/day for 10 days. The study objective was to determine the safety of Aquaflor administered in feed to channel catfish at doses of 0 (control), 10, 30, and 50 mg/kg BW/day for 20 consecutive days. Parameters evaluated included daily mortality, behavioral (appetite, distribution, flight/fright response), and water chemistry observations, initial and terminal weight measurements, and gross and microscopic pathology. Medicated feed consumption was 67-86% of target with group mean doses of 8.5 mg/kg BW/day, 24.6 mg/kg BW/day, and 34.9 mg/kg BW/day. There were no mortalities or clinically observable changes noted at any of the dose levels tested. Aquaflor-related changes were limited to the food consumption and histopathology data. Although Aquaflor-related decreased feed consumption was noted in the 30 and 50 mg/kg BW/day groups, there were no differences in fish growth among the treatment groups. Aquaflor-related histopathology findings were limited to a histomorphologically evident dose-dependent decrease in hematopoietic/lymphopoietic tissue in the anterior kidneys, posterior kidneys, and spleens of channel catfish.

Comparative efficiency of the dietary addition of synbiotic "curazol-M" and norfloxacin on the growth performance, body composition, and histological alteration of the Nile tilapia

“…Herein, in our study, the spleen showed a reduction in lymphocytes and hemosiderin pigments comparing with other groups. The results coordinated with that reported by Gaikowski et al (2003) and Reda et al (2013).…”

The Effects of Florfenicol on the Values of Serum Tumor Necrosis Factor-αand Other Biochemical Markers in Lipopolysaccharide-Induced Endotoxemia in Brown Trout

“…Florfenicol is a broad spectrum antibiotic used for the treatment of bacterial infections in mammals, birds, fish, and lobsters [1, 2, 4, 18, 19]. In this study, sTNF- α values were found to increase after LPS application ( P < 0.05) (Table 1).…”

“…in fish [3]. It has been reported that florfenicol can be safely used at differing doses in tilapia fish and dose related mild decreases in the hematopoietic/lymphopoietic tissues have been observed with its use in channel catfish [4]. …”

Nanoporous Silicon Composite as Potential System for Sustained Delivery of Florfenicol Drug

“…Florfenicol (FF) is the most important antibiotic employed in the aquaculture . In some countries like Japan, South Korea, Norway, Chile, Canada, and United Kingdom, FF is an antimicrobial agent registered for the treatment of susceptible bacterial diseases in several fish species . In the case of the salmonid species, FF is used for the treatment and control of furunculosis caused by Aeromonas salmonicida .…”

“…In some countries like Japan, South Korea, Norway, Chile, Canada, and United Kingdom, FF is an antimicrobial agent registered for the treatment of susceptible bacterial diseases in several fish species . In the case of the salmonid species, FF is used for the treatment and control of furunculosis caused by Aeromonas salmonicida . Although medicated feed is commonly employed in salmon farming to prevent bacterial infections, drugs are not completely ingested or unmetabolized.…”