Antimicrobial use in ecolabel certified and non-certified yellowtail (Seriola quinqueradiata) aquaculture in Japan

Abstract

Given the emergence of antimicrobial-resistant pathogens in aquaculture worldwide, overuse of antimicrobials must be avoided to enhance sustainability in aquaculture. Although the actual usage of antimicrobials has been disclosed in some cultured species, such as salmon, this information is not always available for other species. In this study, with the cooperation of yellowtail farms in Japan, the actual usage of antimicrobials for commercially cultured yellowtail was investigated. In a survey of 28 net pens of cultured yellowtail, an average of 0.95 g (95 % confidence interval 0.78–1.11) of total antimicrobials was used per kilogram of cultured yellowtail. Each of the antimicrobials is listed as a critically or a highly important antimicrobial by the World Health Organization. A comparison of fish cultured according to the sustainability standard established by the Aquaculture Stewardship Council (ASC) with those not cultured according to the standard showed that the total quantity of antimicrobials used was significantly lower for the former than for the latter. However, the quantity of antimicrobial use even for ASC-certified yellowtail was still higher than that for other cultured species. Therefore, further and sustained efforts to reduce antimicrobial use are needed.