Colombian aquaculture mirrors global production trends with increasing numbers. From 2010 to 2020, production increased by 200%, from 80,255 to 179,351 tons, as reported by the Colombian Agricultural Ministry. Remarkably, tilapia culture accounts for 60% of total fish production, placing Colombia as the leading supplier of fresh tilapia to the United States.
Despite joint efforts from both public and private sectors, aquaculture growth has been uneven nationwide. In the central region, particularly in Huila, tilapia production represents 46% of Colombian fish culture. However, other regions with significant potential currently exhibit low production levels. For instance, La Guajira boasts 688,327 hectares suitable for tilapia farming (33% of its territory), yet reports only 24,328 kg/year production, contributing less than 0.5% to the national fish production. This highlights several challenges such as incipient aquaculture productivity among small producers, increased costs, and vulnerability. Furthermore, reliance on high water demand and uncontrolled wastewater release raises environmental concerns. Additionally, in 2023, the country declared a sanitary emergency state due to mass mortalities related to Streptococcus agalactiae IA, affecting up to 85% of tilapia production in some farms.
To address these challenges, we have undertaken the implementation of recirculation culture systems (RAS) alongside biotechnological tools to support the sustainability of tilapia culture as a pivotal strategy for ensuring food security and safety in La Guajira. Specifically, we assessed culturable bacteria and yeast associated with fingerlings, juvenile, and adult tilapia cultured in RAS systems. Microorganisms were screened and selected based on their probiotic potential activity. Lactococcus lactis isolates underwent in vitro and in vivo evaluations to determine their effects on intestinal microbial ecology, weight gain, immune gene expression, and fish survival following an experimental challenge with S. agalactiae.
Additionally, we designed a bacterial culture medium and optimized a bioprocess of encapsulation by spray drying to determine production conditions conducive to obtaining active symbiotic biomass. This eubiotic product maintains high survival capabilities under gastrointestinal fish conditions, exhibits antibacterial activity, and ensures long shelf life stability.