Detection and genotypic characterization of ranavirus (Frog Virus 3) in commercial frog farms of São Paulo and assessment of the susceptibility of bullfrogs (Lithobates catesbeianus) to experimental infection

• Grant number: 15/24590-7
• Support Opportunities: Regular Research Grants
• Duration: March 01, 2016 - February 28, 2018
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Cláudia Maris Ferreira Mostério
• Grantee: Cláudia Maris Ferreira Mostério
• Host Institution: Instituto de Pesca. Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). São Paulo , SP, Brazil
• Associated researchers: Marcio Hipolito ; Ricardo Luiz Moro de Sousa ; SABRINA RIBEIRO DE ALMEIDA QUEIROZ

Abstract

Over 80% of amphibian diversity occurs in tropical regions whose sites are being destroyed by human factors. Among the most reported are water pollution, the presence of alien species and emerging diseases such as chytridiomycosis and ranavirose. The ranavirus whose disease is called Ranavirose is highly virulent to 90% incidence of mortality in most cases. This virus affects fish, reptiles and amphibians. The bullfrog (Lithobates catesbeianus) is currently the only amphibian rearing for commercial consumption in Brazil. It has been reported that ranavirose has high incidence in these organisms is therefore considered a disease of economic importance, causing deaths in frog farms and may also be transmitted to fish farms. In Brazil, studies with ranavirus are incipient. Epidemiological studies are required as much for the understanding of the mechanisms of viral replication and pathogenicity of this group. They need to be conducted for the prevention of infections, disinfection of contaminated environments and economic losses that might occur due to large mortalities. The objective of this project is to perform molecular diagnostic of ranavirus (FV3) followed by isolation in cell cultures from samples of bullfrogs (Lithobates catesbeianus) obtained different frog farms in the state of São Paulo and perform experimental infection in animals in adult and larval stage to assess the susceptibility of these populations. Therefore, the animals will be randomly sampled in four (4) different frog farms of São Paulo state. will be collected 20 adult animals with an average weight of 150 g and 20 tadpoles with an average weight of 7g in each frog farm, totaling 160 individuals for this study. For the diagnosis of ranavirose (PCR), cell isolation and cultivation will be collected the average lobe of the liver, kidneys and spleen of animals. These pooled samples will be processed following the protocol recommended by the OIE 2012. Experimental infection is by oral inoculation with increasing doses of viral particles. It is expected that the results of this study can answer questions about the impact of viral transmission of this pathogen in aquatic systems and improve understanding of the spread of this disease dynamics in Brazil. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

OLIVEIRA, CINTHIA RODRIGUES; ALFAIA, STHEFANY ROSA; IKARI, FERNANDA LIE; TAVARES, LOIANE SAMPAIO; MORO DE SOUSA, RICARDO LUIZ; HARAKAVA, RICARDO; FERREIRA, CLAUDIA MARIS. Detection and molecular characterization of Frog virus 3 in bullfrogs from frog farms in Brazil. Aquaculture, v. 516, FEB 1 2020. (15/24590-7)

CANDIDO, MARCELO; TAVARES, LOIANE SAMPAIO; ALENCAR, ANNA LUIZA FARIAS; FERREIRA, CLAUDIA MARIS; DE ALMEIDA QUEIROZ, SABRINA RIBEIRO; FERNANDES, ANDREZZA MARIA; MORO DE SOUSA, RICARDO LUIZ. Genome analysis of Ranavirus frog virus 3 isolated from American Bullfrog (Lithobates catesbeianus) in South America. SCIENTIFIC REPORTS, v. 9, NOV 20 2019. (16/21357-2, 17/01718-3, 12/08846-3, 15/24590-7)