IDENTIFICATION OF THE PRESENCE OF Mycobacterium spp. IN TILAPIA FROM COMMERCIAL FISH FARMS IN THE STATE OF SÃO PAULO, BRAZIL

INTRODUCTION

 It is estimated that Brazil should record a growth of 104% in fishing and aquaculture production in 2025. According to the study, the increase in Brazilian production will be the highest recorded in Latin America, followed by Mexico (54.2%) and Argentina (53.9%) over the next decade. Globally, production should grow to reach 195.9 million tons by 2025. Studies indicate that this commodity is one of the highest risk associated with its consumption considering the diversity of related pathogens (bacteria, viruses, parasites, chemicals and toxins ), many of these zoonoses pathogens. In aquaculture, in fish, reptiles, amphibians and crustaceans the bacteria have caused great losses in the production by death of the infected animals. Mycobacterium marinum, M. fortuitum and M. chelonae are the main agents of the disease called mycobacteriosis or tuberculosis of wild or native fish, which is a granulomatous disease. This work aims to identify the presence of Mycobacterium spp. in tissue samples from commercial fish farms, contributing to know the extent of the presence and distribution of this pathogen in the State of São Paulo.

MATERIAL AND METHODS

The methodology used was the active collection of 40 tilapias and subsequent histological analysis with H & E routine staining to visualize the presence of granulomas in microscopy, histochemistry using the Ziehl-Neelsen (ZN) technique with Fite-Faraco variation.

RESULTS AND CONCLUSION

The presence of 53% (n = 23) of granulomatous lesions was observed, however, 5 were positive in ZN. It is concluded that although only 5 are positive for the presence of Mycobacterium spp., It is suggested that there may have been infection by another agent that also causes granulomas causing great economic losses in fish farming, which highlights the importance of histochemical techniques for diagnosis .