From Pig Breeding Environment to Subsequently Produced Pork: Comparative Analysis of Antibiotic Resistance Genes and Bacterial Community Composition

Abstract

It is well verified that pig farms are an important reservoir and supplier of antibiotic resistance genes (ARGs). However, little is known about the transmission of ARGs between the breeding environment and subsequently produced pork. This study was conducted to investigate if ARGs and associated host bacteria spread from the breeding environment onto the meat through the food production chain. We thus analyzed the occurrence and abundance of ARGs, as well as comparing both ARG and bacterial community compositions in farm soil, pig feces and pork samples from a large-scale pig farm located in Xiamen, People’s Republic of China. Among the 26 target ARGs, genes conferring resistance to sulfonamide, trimethoprim, aminoglycoside, chloramphenicol, macrolide, florfenicol, and tetracycline were observed at high frequency in both the pig breeding environment and pork. The prevalence of ARGs in pork was surprisingly consistent with breeding environments, especially between the pork and feces. The relative abundance of 10 representative ARGs conferring resistance to six classes of antibiotics ranged from 3.01 × 10-1 to 1.55 × 10-6 copies/16S rRNA copies. The ARGs conferring resistance to sulfanilamide (sulI and sulII), aminoglycoside (aadA), and tetracycline [tet(A) and tet(M)] were most highly abundant across most samples. Samples from feces and meat possessed a higher similarity in ARG compositions than samples from the farms soil. Enterobacteriaceae found on the meat samples were further identical with previously isolated multidrug-resistant bacteria from the same pig farm. Our results strongly indicate that ARGs can be potentially spreading from pig breeding environment to meat via the pork industry chain, such as feed supply, pig feeding and pork production.

Diverse Mobile Genetic Elements and Conjugal Transferability of Sulfonamide Resistance Genes (sul1, sul2, and sul3) in Escherichia coli Isolates From Penaeus vannamei and Pork From Large Markets in Zhejiang, China

“…Moreover, sulfonamides are among the most commonly used antibiotics at swine farms, second only to tetracyclines (Hsu et al, 2014), and are widely used in P. vannamei culture for the prevention and treatment of common bacterial diseases (Gao et al, 2012). Excessive usage of sulfonamides in the shrimp farming and pig breeding industries in China imposes widespread selective pressures on bacteria, leading to the enrichment of sulfonamide resistant strains in shrimp and pork products that are capable of spreading between different environments (Liu et al, 2019; Yuan et al, 2019). In our study, P. vannamei and pork were chosen to study the prevalence of sulfonamide resistance in three large markets in Zhejiang, China to assess (i) whether differences occur in the distribution of sul genes in Escherichia coli isolates from samples of two different host species collected from markets, (ii) whether vertical or horizontal transmission of sulfonamide resistant E. coli occurs between P. vannamei and pork in market environments, despite the different growth conditions of the two animals and (iii) whether regional spreading of sulfonamide resistant E. coli in the same or different host species occurs between different markets.…”

Prevalence, Characteristics and Clonal Distribution of Extended-Spectrum β-Lactamase- and AmpC β-Lactamase-Producing Escherichia coli Following the Swine Production Stages, and Potential Risks to Humans

“…Collectively, these enhanced properties, namely MDR, multiple virulence factors, and enhanced biofilm formation ability, of ESBL/AmpC-EC from swine farms could make them difficult to be controlled once introduced to swine farms, allowing ESBL/AmpC-EC to survive and continue to exist within swine farms. In addition, the ESBL/AmpC-EC, with these properties, in swine farms could be transmitted to humans through the chain of pig meat ( Liu et al, 2019 ), direct contact with the farm workers ( Schmithausen et al, 2015 ), and manure excretion into the farm’s surrounding environment, including soils, ponds, and rivers ( Furlan and Stehling, 2018 ). Spread of ESBL/AmpC-EC strains can be of serious public health concern since it could aid in the emergence of pathogens, which are difficult to control in the food-animal industry as well as human hospitals ( Yoo et al, 2010 ; Dantas Palmeira and Ferreira, 2020 ).…”

“…The possibility of ESBL-EC transmission from swine farms to humans has been continuously proposed and vice versa ( Bok et al, 2020 ; Song et al, 2020 ). Various ESBL/AmpC-EC transmission routes have been suggested, including the food-chain of pigs ( Liu et al, 2019 ), direct contacts of farm workers with pigs ( Schmithausen et al, 2015 ), and manure excretion into the surrounding environment in farms such as soils, ponds, and rivers ( Furlan and Stehling, 2018 ).…”

Sensitive enzyme‐linked immunosorbent assay and gold nanoparticle immunochromatocgraphic strip for rapid detecting chloramphenicol in food

“…The strip can provide a fast and easy onsite detection in less than 10 min by visible results (Liu et al, ; Zhou et al, ). Since the contamination of CAP in milk and honey has been reported in China and other countries (Liu, Klumper, Shi, Ye, & Li, ; Ronning et al, ; Shim et al, ; van de Water et al, ; Wang, Zhang, Gao, Duan, & Wang, ; Zhou et al, ). In this study, specific polyclonal antibodies for CAP was obtained and applied to sensitive enzyme‐linked immunosorbent assay (ELISA) and immunostrip for the rapid determining CAP in milk and honey.…”

“…The strip can provide a fast and easy onsite detection in less than 10 min by visible results (Liu et al, 2014;Zhou et al, 2014). Since the contamination of CAP in milk and honey has been reported in China and other countries (Liu, Klumper, Shi, Ye, & Li, 2019;Ronning et al, 2006;Shim et al, 2006;van de Water et al, 1987;Wang, Zhang, Gao, Duan, & Wang, 2010;Zhou et al, 2014).…”