Molecular Epidemiology of Aquaculture Pathogens in Rainbow Trout (Oncorhynchus mykiss) using Real-time PCR in Peruvian Andean Environments

Rainbow trout (Oncorhynchus mykiss) is one of the main aquaculture species cultivated in the high Andean regions of Peru, providing food security and rural socioeconomic development. However, the area is frequently affected by infectious agents that compromise fish health and generate significant economic losses. The objective of this study was to determine the prevalence and regional distribution of the main infectious pathogens in rainbow trout using molecular techniques.

Biological samples were collected from five producing regions (Junín, Puno, Pasco, Lima and Ayacucho) and analyzed using real-time quantitative polymerase chain reaction (qPCR) for the detection of relevant bacterial and viral pathogens in trout farming.

The results showed the presence of various etiological agents, with Flavobacterium sp. being the most prevalent pathogen, representing 46.2% of positive samples. Other pathogens such as infectious pancreatic necrosis virus (IPNV), Weissella sp., Aeromonas sp. and Yersinia sp. were also identified. A higher frequency of infectious pathogens were found in the Junín and Puno regions, coinciding with areas of greatest production activity. These findings highlight the need to strengthen health surveillance, biosecurity and timely diagnosis programs in intensive high-Andean systems, to reduce the health and economic impact of infectious diseases on trout production in Peru.