Disease Prevalence, Usage of Aquaculture Medicinal Products and Their Sustainable Alternatives in Freshwater Aquaculture of North-Central Bangladesh.

Abstract

Background: The use and abuse of aquaculture medicinal products (AMPs) has increased throughout the globe to enhance fish production and maximize profits. This study aimed to investigate the status of disease prevalence and usage of AMPs in aquaculture operations in North-Central Bangladesh, a region famous for its significant carp and catfish production within the Asian subcontinent. Farmers in this area are recognized for their innovative approaches to aquaculture.

Methods: Data were collected through pretested questionnaire interviews and participatory rural appraisal (PRA) tools.

Results: Among the 90 surveyed grow-out farmers, the majority practiced mixed cultures of carps, Nile tilapia and catfish (primarily Pangasius) where diseases such as epizootic ulcerative syndrome (EUS), saprolegniasis, streptococcosis, tail and fin rot and bacillary necrosis were common. Despite the widespread use of AMPs, their efficacy is often limited, and their overuse can contribute to the development of antibiotic-resistant bacteria and environmental pollution. Additionally, the extra-label drug use (ELDU) has become an issue that results in controversial application of drugs by fish farmers. All together 142 AMPs of different groups were marketed by 24 companies, including antibiotics, disinfectants, nutritional supplements, probiotics, gas remover and salt. Among these, 3 groups of antibiotics with 11 active ingredients were identified, sold under 17 trade names in drug retail outlets. These antibiotics, originally intended for veterinary or poultry use, were often misapplied in aquaculture, raising concerns about ELDU practices. Due to the limited efficacy of many of these antibiotics, farmers adopted alternative approaches such as in-pond probiotics and fermented products. It was revealed that 12% (11 out of 90) of the farmers were using these alternatives that led to approximately 20% approved fish growth with a cost reduction up to 30% compared to the conventional culture cycles. Farmers also reported a reduction in disease outbreaks in ponds managed with these alternatives.

Conclusions: Promotion of sustainable and responsible practices is essential for the long-term growth of aquaculture industry. It is expected that the use of probiotics and fermented products can reduce the reliance on conventional AMPs, thereby contributing to enhanced food security and economic development in Bangladesh.