Simultaneous analysis of 21 sulfonamides, trimethoprim, ormetoprim, and dapsone in fish and shrimp samples by LC-MS/MS using the QuEChERS method

Residue Depletion Profile and Estimation of Withdrawal Period for Sulfadimethoxine and Ormetoprim in Edible Tissues of Nile Tilapia (Oreochromis sp.) on Medicated Feed

“…However, bacterial infection is a significant challenge to fish farming systems, causing substantial economic losses. Thus, antimicrobials are commonly used in aquaculture to treat animal diseases and mitigate losses [5,6].…”

“…The most used antimicrobials in aquaculture worldwide are amoxicillin, enrofloxacin, erythromycin, tetracycline, florfenicol, flumequine, sarafloxacin, sulfadimethoxine, ormetoprim, and oxytetracycline [10,11]. Sulfonamides are commonly used in farmed fish, including combinations with trimethoprim and ormetoprim [5].…”

“…Sulfadimethoxine (SDM) is a relatively potent and long-acting sulfonamide that is effective when used alone or in combination with ormetoprim (OMP) in treating bacterial infections [12,13]. Rapid absorption, short half-life, increase in efficacy as well as lower incidence of bacterial resistance are some of the attributes of these drugs in combination [5,14]. A good example is Romet 30 ® , an antibacterial drug approved in the United States, Canada, and other countries which contains SDM and OMP in a ratio of 5:1 and is recommended for applications such as the control of furunculosis in freshwater-reared salmonids (trout and salmon) caused by Aeromonas salmonicida, and the control of bacterial infections in catfish caused by Edwardsiella ictaluri (enteric septicemia of catfish) [15,16].…”

“…Despite the effectiveness and broad spectrum of action of the combination of SDM and OMP, the use of these antimicrobials in fish farming is not regulated in many countries, such as Brazil, which currently has only two antimicrobials (florfenicol and oxytetracycline) regulated for use in this system [18]. Although SDM and OMP help in reducing the incidence of infectious diseases, their use may lead to residues in food products, posing potential health risks to consumers such as allergic reactions, carcinogenesis, or induction of the development of pathogenic bacteria-resistant strains [5,19,20]. Thus, the Maximum Residue Limits (MRLs) in foodstuffs of animal origin have been established for these and other veterinary drug residues [19,21].…”