TY - JOUR
T1 - Efficacy of florfenicol for control of mortality associated with Francisella noatunensis subsp. orientalis in Nile tilapia, Oreochromis niloticus (L.)
AU - Soto Martinez, Esteban
AU - Kidd, S.
AU - Gaunt, P. S.
AU - Endris, R.
PY - 2013/4
Y1 - 2013/4
N2 - Francisella noatunensis subsp. orientalis (Fno) (syn. F. asiatica) is an emergent Gram-negative facultative intracellular bacterium. Although it is considered one of the most pathogenic bacteria in fish, there are no commercially available treatments or vaccines. The objective of this project was to determine the most efficacious concentration of florfenicol (FFC) [10, 15 or 20 mg FFC kg-1 body weight (bw) per days for 10 days] administered in feed to control experimentally induced infections of Fno in Nile tilapia, Oreochromis niloticus (L.), reared in a recirculating aquaculture system. The cumulative mortality of fish that received 0, 10, 15 or 20 mg FFC kg-1 bw per day was 60, 37, 14 and 16%, respectively. Francisella noatunensis subsp. orientalis genome equivalents were detected in water from all challenged groups with slight reduction in the concentration in the florfenicol-treated groups 4 days after treatment. The mean LOG of CFU Fno mg-1 spleen was 3-5 and was present in all challenged groups at necropsy 11 days after treatment (21 days after challenge). Results show that florfenicol administered at doses of 15 and 20 mg FFC kg-1 bw per days for 10 days significantly reduced mortality associated with francisellosis in Nile tilapia.
AB - Francisella noatunensis subsp. orientalis (Fno) (syn. F. asiatica) is an emergent Gram-negative facultative intracellular bacterium. Although it is considered one of the most pathogenic bacteria in fish, there are no commercially available treatments or vaccines. The objective of this project was to determine the most efficacious concentration of florfenicol (FFC) [10, 15 or 20 mg FFC kg-1 body weight (bw) per days for 10 days] administered in feed to control experimentally induced infections of Fno in Nile tilapia, Oreochromis niloticus (L.), reared in a recirculating aquaculture system. The cumulative mortality of fish that received 0, 10, 15 or 20 mg FFC kg-1 bw per day was 60, 37, 14 and 16%, respectively. Francisella noatunensis subsp. orientalis genome equivalents were detected in water from all challenged groups with slight reduction in the concentration in the florfenicol-treated groups 4 days after treatment. The mean LOG of CFU Fno mg-1 spleen was 3-5 and was present in all challenged groups at necropsy 11 days after treatment (21 days after challenge). Results show that florfenicol administered at doses of 15 and 20 mg FFC kg-1 bw per days for 10 days significantly reduced mortality associated with francisellosis in Nile tilapia.
KW - Florfenicol
KW - Francisella noatunensis subsp. orientalis
KW - Nile tilapia
UR - http://www.scopus.com/inward/record.url?scp=84874981828&partnerID=8YFLogxK
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U2 - 10.1111/j.1365-2761.2012.01425.x
DO - 10.1111/j.1365-2761.2012.01425.x
M3 - Article
C2 - 23134104
AN - SCOPUS:84874981828
VL - 36
SP - 411
EP - 418
JO - Journal of Fish Diseases
JF - Journal of Fish Diseases
SN - 0140-7775
IS - 4
ER -