Latin American & Caribbean Aquaculture 2019

November 19 - 22, 2019

San Jose, Costa Rica

EPITHELIOCYSTIS IN NILE TILAPIA Oreochromis niloticus IN COSTA RICA

Guevara-Soto M1 ,  Calderón S1, Coto J1, Blanco T1, Méndez1, Chaves Y1, Guevara M1,, Schmidt-Posthaus H2 , Hirschi R2
 
1  National Technical University, Costa Rica
2  Centre for fish and wildlife  Health (FIWI), University of Bern
 

Introduction: Epitheliocystis is a skin and gill bacterial disease worldwide spread in freshwater and marine fish, a total of 90 species have been

affected by the disease and has been causing high mortalities in wild fish and aquaculture farms.

The disease is caused by an intracellular bacteria the most common pathogens are chlamydial or betaproteobacterium.

The target organ in Nile tilapia is the gill, but usually no gross lesions are seen, the microscopy reveal the presence of multiple cysts that vary from 14 to 30 microns with a basophilic granular material into the cyst.

Methodology:  In Costa Rica, epitheliocystis has been observed in several farms but not reported as a main disease of mortality in Nile tilapia, this case is found in an aquaculture facility, necropsy was performed in fingerlings of 5 cm length and no mortalities were reported ,gills and other organs were collected for histopathology examination.

The microscopy reveal the presence of a multifocal cysts in several lamellas , the cyst had different sizes and consists of agranular basophilic material , the cyst were in the lamella tissue causing compression of the normal structures.

Results:  Gill DNA extraction , PCR and sequencing will be performed in order to detect the bacterial agent affecting Nile tilapia in Costa Rica.

Conclusions: the results for the PCR and the sequencing we will  be able to know the agent that causes this lesion in tilapia costa rican farms.

Funding of presentation:

 National Technical University, Costa Rica