Aquaculture 533 (2021) 736195 Available online 27 November 2020 0044-8486/© 2020 Elsevier B.V. All rights reserved. Aquaculture management practices associated with antimicrobial residues in Southwestern Nigeria Reuben Chukwuka Okocha a, * , Isaac Olufemi Olatoye b , Peter Ibukun Alabi b , Modupe Ganiyat Ogunnoiki c , Olufemi Bolarinwa Adedeji b a Department of Agriculture, Landmark University, Omu-Aran, Kwara State, Nigeria b Department of Veterinary Public Health and Preventive Medicine, University of Ibadan, Ibadan, Nigeria c Aquatic Animal Health Unit, Federal Department of Fisheries, Federal Ministry of Agriculture and Natural Resources, Nigeria A R T I C L E INFO Keywords: Aquaculture production Clarias gariepinus Antimicrobial drugs Food safety Risk ABSTRACT Aquaculture production has grown rapidly in Nigeria but with unbridled use of antibiotics which predisposes fsh consumers to the risks of antimicrobial residues and resistance. A cross sectional survey of antimicrobial use in aquaculture and occurrence of their residues in African Catfsh (Clarias gariepinus) samples from Southwestern states of Nigeria were carried out. The results showed that majority of the farmers lacked knowledge of drug residues in aquatic animals, and the food safety and public health implications on consumers. Frequently administered antibiotics include tetracyclines (27.5%), chloramphenicol (22.0%) and gentamicin (18.4%). About 84.7% of tested fsh had residues with variable prevalence which were not statistically signifcant. Risk factor analysis indicated that fsh farmers with tertiary and secondary education were more likely to produce fsh that contained antimicrobial residues than those with primary education [odds ratio (OR) = 1.91, confdence interval (CI) = 1.24–5.99 and OR = 1.25, CI = 1.08–5.27, respectively] while fsh from farms managed by men were about three times more likely to contain residues (OR = 3.25, 95% CI = 1.95–9.35) than those managed by women. Hence, most of the fsh from Southwestern Nigeria were indiscriminately dosed with different antibiotics that predispose consumers to the risks of antimicrobial residues with food safety and antimicrobial resistance consequences. Implementation of good fshery management practices and farmers’ education are advocated to reduce dependence on antimicrobials. 1. Introduction Aquaculture is an important sector of Nigerian economic develop- ment, more so with the government diversifcation of the oil-based economy. It is greatly contributing to the national food security, generating employment for the good proportion of Nigerians and with potentials to generate foreign exchange in international trade in fsh and shrimps (FDF, 2008; Kareem et al., 2008). Fish is a regular portion of many Nigerians’ diet as a source of animal protein, vitamins and min- erals. In addition, fsh products are relatively cheaper than beef, pork and other animal protein sources in the country (Dauda and Yakubu, 2013). Fish, especially catfsh, are relished as a delicacy among Niger- ians for home consumption or at fast food joints and restaurants (Ola- toye and Basiru, 2013). Aquaculture production in Nigeria is increasing with increasing population and demand for protein in food. Intensifcation of aquaculture practices is accompanied by outbreaks of infectious diseases that require treatment (Bondad-Reantaso et al., 2005). Natural and synthetic chemicals such as antimicrobials, disinfectants, parasiticides, probiotics, and other feed additives have become indispensable inputs to treat and prevent bacterial and parasitic diseases in aquaculture, to improve water quality and as growth promoters (Rico et al., 2012). While the use of these substances has been disapproved, it has contrib- uted to the development and growth of the aquaculture sector in Nigeria. The use of antibiotics in aquaculture systems can create serious economic and health problems. Antibiotic residues have been found in several aquatic products from Vietnam and other Asian countries (Canada-Canada et al., 2009; Won et al., 2011; He et al., 2012). As a result of stringent regulations from the U.S. and European Union (EU), the issue of antibiotic residues in aquatic products for export has been mostly resolved; however, there are no such well enforced regulations * Corresponding author at: Department of Agriculture, Landmark University, P. M. B. 1001, Omu-Aran, Kwara State, Nigeria. E-mail address: okocha.reuben@lmu.edu.ng (R.C. Okocha). Contents lists available at ScienceDirect Aquaculture journal homepage: www.elsevier.com/locate/aquaculture https://doi.org/10.1016/j.aquaculture.2020.736195 Received 19 August 2020; Received in revised form 1 November 2020; Accepted 22 November 2020