*Fish species: 1- freshwater angelfish, Pterophyllum scalare; 2-pacu, Piaractus mesopotamicus; 3- cachara, Pseudoplatystoma reticulatum and 4-

Nile tilapia, Oreochromis niloticus.

INTRODUCTION

THIAMPHENICOL: IN VITRO ACTIVITY AGAINST BACTERIA PATHOGENIC TO FISH

Inácio M. Assane1,2*, Katia S. Gozi2, Gustavo M. R. Valladão2, and Fabiana Pilarski2

Laboratory of Parasitology and Microbiology of Aquatic Organisms, São Paulo State University (UNESP), Aquaculture Center of Unesp, Jaboticabal, SP, Brazil, 14870

inaciomateusassane@gmail.com

• Thiamphenicol (TAP) is a structural analogue of chloramphenicol

(CAP)(Fig.1)andhavesimilar antibacterial spectrum.

• TAP is widely used as an antibacterial both in human and

veterinary medicine and it has been proposed for the treatment

of vibriosis and pasteurellosis in fish farm.

• The present study aimed to investigate the in vitro

susceptibility to TAP of 30 strains of bacteria isolated from

1 2“Sustainable Aquaculture – New Frontiers for Economic Growth”

MATERIALS AND METHODS

RESULTS AND DISCUSSION

Table 1- Antibacterial activity of TAP against freshwater fish pathogens.

• Aeromoniosis, lactococcosis and vibriosis are one of the most important diseases in aquaculture worldwide and these findings

suggest thepotential of TAP asa treatment option for thesediseases.

Strains used (n) Fish specie* Period of isolationTAP antibacterial activity (µ𝐠 𝐦𝐋−𝟏)

MIC MBC

Aeromonas caviae (1) 4 2014 8 8

Aeromonas hydrophila (8) 2 and 4 2011-2015 1 - 32 2 - 32

Aeromonas jandaei (2) 4 2011-2013 1 - 2 2

Aeromonas veronii (1) 2 2014 1 2

Citrobacter freundii (2) 1 and 3 2012-2015 64 64 - 256

Enterococcus casseliflavus (2) 4 2010-2011 16 - 64 >128 - >256

Lactococcus garviae (3) 3 and 4 2011-2012 2 - 4 >8 - >16

Pseudomonas fulva (2) 4 2011-2012 128 - >1024 >512

Streptococcus agalactiae (6) 4 2014-2016 128 >512

Vibrio spp. (3) 2 2016 2 - 128 4 - <512

CONCLUSION

• TAP demonstrated highly potent antibacterial activity against Aeromonas spp., Lactococcus spp. and Vibrio spp.,

although in some strains of Aeromonas spp. and Vibrio spp. it was somewhat less sensitive (>8 µg mL-1) (Table 1).

ACKNOWLEDGENTS:• CNPq, processo nº 190049/2015-4;

• DES-VET: Produtos Veterinários.

different freshwater fishes during disease outbreaks in Brazil.

Fig.1. Chemical structure of TAP and its related compounds.

Culture medium Two-fold dilution (1st - 18th)1 2 Inoculation3 Interpretation4