Evidence of shared gut pathogens in Cultured Fishes and Aquaculture-related wildlife species

Aquaculture in Nigeria plays a vital role in food production, income generation, and employment, owing to the country’s vast coastline and abundant water resources. However, aquaculture systems frequently interact with wildlife species such as crabs, birds, reptiles, amphibians, and mammals, creating opportunities for pathogen transfer. The occurrence and implications of shared pathogens between cultured fish and aquaculture-related wildlife species remain poorly documented. This study investigated the presence of shared gut bacterial pathogens between cultured fishes and aquaculture-associated wildlife, as well as fish farmers’ knowledge of pathogen transfer and zoonotic risks. Data were obtained using interviewer-administered questionnaires from two purposively selected fish farms in Ibadan. Sample collection included cultured fish (n=8), crabs (n=7), and a bird (n=1). Gut samples were processed for bacterial isolation and identification using TCBS agar and Pseudomonas Cetrimide agar, following standard protocols. Findings revealed that 85.71% (n=18) of fish farmers had encountered aquaculture-related wildlife species, yet only 33.33% (n=7) recognized the possibility of pathogen transfer to cultured fish, and 28.57% (n=6) were aware of potential zoonotic transmission. Laboratory analysis confirmed 17 isolates of Vibrio spp. and 17 isolates of Pseudomonas spp. in all fish samples. Additionally, 5 (62.5%) of the crab and bird samples were positive for Pseudomonas, while 7 (87.5%) tested positive for Vibrio. This study provides the first documented evidence of shared gut pathogens (Vibrio spp. and Pseudomonas spp.) between cultured fishes and aquaculture-related wildlife species in Nigeria. The findings highlight potential public health risks, underscore the need for improved surveillance, and provide baseline data for strengthening aquaculture biosecurity and One Health strategies.