title: Genotoxic responses of juvenile tilapia (Oreochromis niloticus) exposed to florfenicol and oxytetracycline.
abstract: Florfenicol (FLC) and oxytetracycline (OTC) are the two most commonly used antibiotics for bacterial treatment in fish farming in Brazil, and because of their intensive use, the potential harmful effects on aquatic organisms are of great concern. This study evaluated the effects of environmental concentrations of FLC and OTC on the genetic material of juvenile tilapia (Oreochromis niloticus) erythrocytes by using the comet assay and the occurrence of micronuclei (MN) and other erythrocytic nuclear abnormalities (ENAs) after exposure to 96hour. The comet assay showed that fish erythrocytes exhibited significantly higher DNA damage after exposure to environmental concentrations of FLC and OTC. Although MN was not observed, ENAs were significantly higher after exposure to FLC, indicating that ENAs are a better biomarker for FLC than MN. The results showed that environmental concentrations of FLC and OTC were genotoxic to erythrocytes of O. niloticus; however, future studies on DNA damage recovery are needed.
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo - CENA/USP, Avenida Centenário, 303, São Dimas, Piracicaba, São Paulo 13416-000, Brazil. Electronic address: rbotelho@cena.usp.br.
authors.forename: R G
authors.initials: RG
authors.lastname: Botelho
authors.affiliation: Centro Universitário Hermínio Ometto - FHO/UNIARARAS, Av. Dr. Maximiliano Baruto, Araras, São Paulo 13607-339, Brazil. Electronic address: cintyachris@gmail.com.
authors.forename: C A
authors.initials: CA
authors.lastname: Christofoletti
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho, Avenida 24 A, 1515, Rio Claro, São Paulo 13506-900, Brazil. Electronic address: jorgeecorreia@hotmail.com.
authors.forename: J E
authors.initials: JE
authors.lastname: Correia
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho, Avenida 24 A, 1515, Rio Claro, São Paulo 13506-900, Brazil. Electronic address: yansoar@gmail.com.
authors.forename: Y
authors.initials: Y
authors.lastname: Ansoar
authors.affiliation: Universidade Estadual da Paraíba - UEPB, Campus I - Centro de Ciências e Tecnologia, Departamento de Estatística, Avenida das Baraúnas, 351, Bodocongó, Campina Grande, Paraíba 58101-001, Brazil. Electronic address: ricardo.estat@yahoo.com.br.
authors.forename: R A
authors.initials: RA
authors.lastname: Olinda
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo - CENA/USP, Avenida Centenário, 303, São Dimas, Piracicaba, São Paulo 13416-000, Brazil. Electronic address: vltornis@cena.usp.br.
authors.forename: V L
authors.initials: VL
authors.lastname: Tornisielo
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000633:toxicity*; D023681:Cichlids / Q000235:genetics*; D020552:Comet Assay; D004249:DNA Damage; D004912:Erythrocytes / Q000187:drug effects; D015162:Micronucleus Tests; D010118:Oxytetracycline / Q000633:toxicity*; D013839:Thiamphenicol / Q000031:analogs & derivatives* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D000900:Anti-Bacterial Agents; D014874:Water Pollutants, Chemical; C035534:florfenicol; D013839:Thiamphenicol; D010118:Oxytetracycline
keywords: Antibiotic; Comet assay; Fishes; Micronuclei; Nuclear abnormalities