Tetracycline Resistance in Escherichia Coli Isolates From Poultry

Abstract

The objectives of the present paper are the analysis and comparison of the results from available literature regarding the prevalence of tetracyclineresistance in Escherichia coli strains isolated from poultry in different countries. Tetracycline is still one of the most commonly used antibiotic in many developing countries both in human and in veterinary medicine. The main reasons are its relatively low cost and availability. Besides that, this class of antibiotics is still used in developed countries for prophylactic and therapeutic purposes. Th e widespread use of tetracycline in poultry farming could result in horizontal transfer of resistance determinates from poultry to humans as well as to the environment. Escherichia coli, is a commensal bacteria from human and poultry digestive systems, and present one of the most important reservoirs of antibiotic resistance and has a signifi cant role in the transfer of various resistance determinants. Some strains of Escherichia coli are highly pathogenic and can cause several diseases in poultry which require antibiotic therapy. Positive correlation between the usage of antibiotics both in human and in veterinary medicine and the corresponding antibiotic resistance were reported by many authours. Furthermore, there is also some evidence that the positive correlations were also found between the usage of antibiotics in veterinary medicine and the appereance of antibiotic resistance in bacteria isolated from humans. Th e prudent use of tetracycline antibiotic in poultry production is essential as well as permanet monitoring of the presence of the tetracycline resistance.

Antibiotic Resistance of Escherichia Coli Isolated from Broiler Chickens

“…Tetracycline resistance has been reported in poultry even without any previous administration of this antibiotic [2]. Due to frequent oc-currence, E. coli strains resistant to tetracycline can be used as an indicator of antibiotic-resistant bacteria in poultry farming [8].…”

“…On the contrary, Z i b a n d e h et al [24] reported the tet(A) to be the only tetracycline resistance gene detected in 72.5 % of E. coli isolates taken from the chickens on the day before slaughter.Tetracyclines are broad spectrum antibiotics used in all food-producing animals (including poultry) because they are cheap and easily available. Therefore, the widespread use of tetracyclines often leads to resistance[3] not only among pathogenic, but also commensal intestinal bacteria, such as E. coli[8], resulting in the transmission of resistant bacterial strains from poultry to humans via the food chain[9]. In E. coli, the genes tet(A), tet(B), tet(C), tet(D), and tet(E) are associated with an efflux mechanism and make an important part of the tetracycline resistance[3].It is a well-known fact that integrons play an important role in the dissemination of antimicrobial resistance among Gram-negative bacteria.…”

Molecular detection of genes encoding resistance to tetracycline and determination of plasmid-mediated resistance to quinolones in avian pathogenic Escherichia coli in Sukabumi, Indonesia

“…The relationship between the use of TE as a growth promoter in the poultry industry and the development of resistance has been established by many authors during the past decades. Such long-term subtherapeutic use of TE antibiotics in feed is of great concern because it leads to selective pressure on the E. coli carried by the poultry and also in the farms environment, so the beneficial effects of TE will become limited as bacterial resistance increases [6]. Detection of the respective genes encoding resistance to TE raises a possibility to analyze epidemiological aspects of the resistance and to discover mobile genetic elements that may have contributed in the dissemination of the TE resistance genes ( tet ) in nature [5].…”

“…The resistance mechanisms for the TE class of antibiotics fall in four categories such as energy-dependent efflux pumps, ribosomal protection proteins, enzymatic inactivation, and target modification are recognized as mediators of TE resistance in bacteria. The genes associated with an efflux mechanism, namely tet ( A ), tet ( B ), tet ( C ), tet ( D ), and tet ( E ), are important part of TE resistance in E. coli [6]. Other antibiotic agents that used to treat infections caused by this bacterium include fluoroquinolones, newer quinolones containing a fluorine atom.…”

Antimicrobial Resistance in Escherichia coli Strains Isolated from Humans and Pet Animals

“…As already stated, antibiotic resistance found in microorganisms presents a big challenge for medical practice in the whole world [ 57 , 58 , 59 , 60 , 61 ]. This is to a great extent the consequence of wrong or uncritical consumption of antibiotics.…”