Potential Influence of Regulation of the Food Value Chain on Prevalence and Patterns of Antimicrobial Resistance: the Case of Tilapia (Oreochromis niloticus)

Abstract

The current study was designed to evaluate the potential impact of the level of regulation on the prevalence and patterns of antimicrobial agent resistance in bacteria isolated from fish. The study sites included two large lakes and both semi-regulated and unregulated fish value chains. A total of 328 bacterial isolates belonging to 11 genera were evaluated for antimicrobial susceptibility testing using disk diffusion method. The bacteria species were tested against 12 different antibiotics (trimethoprim-sulfamethoxazole, tetracycline, ampicillin, cefotaxime, chloramphenicol, nalidixic acid, amoxicillin, meropenem, ciprofloxacin, nitrofurantoin, cefuroxime and kanamycin). Data analysis was done to assess the heterogeneity in proportion of resistant bacterial species within and between the two value chains using a random-effects model proposed by DerSimonian and Laird. Statistical heterogeneity within and between groups were estimated using the Cochran Chi -square test and the Cochrane- I 2 . Overall proportion of bacterial species resistant to antimicrobial agents in semi-regulated and unregulated value chains ranged from 0.00 to 0.88 and 0.09 to 0.95, respectively. Shigella spp. had the highest proportion of bacteria that were resistant against most of the antimicrobial agents used. The bacterial species were highly resistant to ampicillin and amoxicillin and the highest multi-drug resistance capacity was observed in Shigella spp. (18.3%, n = 328), Vibrio spp. (18.3%) and L. monocytogenes (12.2%). We observed strong heterogeneity within and between the two value chains regarding proportion of resistant bacterial species. Sun dried fish in both value chains had significantly high proportion of resistant bacterial species. Comparing the two value chains, unregulated value chain had significantly higher proportion of bacterial species that were resistant. In order to mitigate the risk of transmitting antimicrobial resistant bacteria to consumers along the fish value chain, good manufacturing practices coupled with identification and management of possible sources of contamination are recommended for fish and potentially other foods distributed along the less regulated value chains. Importance In order to mitigate the risk of transmitting antimicrobial resistant bacteria to consumers along the fish value chain, good manufacturing practices coupled with identification and management of possible sources of contamination are recommended for fish and potentially other foods distributed along the less regulated value chains.

Antibiotic resistance gene-free probiont administration to tilapia for growth performance and Streptococcus agalactiae resistance

“…Antimicrobial-resistant bacteria have been extensively reported in various aspects of aquaculture, including fish, sediment, and water. Moreover, the relationship between fish and their environment has been investigated in species [43,44] such as channel catfish, Ictalurus punctatus [45], Alburnus alburnus [46], sea bass [47], yellow tail fish [48], common carp and koi carp [49], shrimp [50], Ebro barbel (Luciobarbus graellsii), brown trout (Salmo trutta) [51], and tilapia (Oreochomis niloticus) [52,53]. Other sectors, such as animal husbandry and household waste, influence resistance genes in aquaculture [54][55][56][57][58][59][60][61][62][63][64][65][66].…”