Antibiotic Resistance of Profiles of <i>Escherichia coli</i> Strains From Imported Chicks and Eggs in the Semi-Intensive Poultry Sector of Kinshasa, Democratic Republic of the Congo

Poultry production in the Democratic Republic of Congo can be divided into three sectors: large-scale, semi-intensive, and backyard production. Kinshasa, capital city of the Democratic Republic of Congo, hosts a number of large-scale and semi-intensive farms that import the majority of their day-old chicks and fertilized eggs. These imports are carried out legally, and both the chicks and eggs arrive by air. They could introduce pathogenic bacteria, including antibiotic-resistant strains. This study aimed to assess the level of antibiotic resistance in E. coli strains isolated from fecal samples of imported chicks and locally hatched chicks from imported eggs in the semi-intensive poultry production system in Kinshasa. This study was conducted from September 15, 2019, to April 15, 2020. Five (56%) importers and hatcheries based in Kinshasa agreed to participate and to inform the team of incoming batches. The team was made aware of five batches. Cloacal samples were collected from egg-laying chicks imported from Belgium (two batches), broiler chicks imported from Zambia (two batches), and broiler chicks hatched locally from incubated eggs imported from an unidentified country (one batch). Samples underwent biochemical identification for E. coli and antimicrobial resistance testing using the disk diffusion method. E. coli was detected in all cloacal samples. Antibiotic susceptibility testing revealed high resistance to amoxicillin (76%), trimethoprim/sulfamethoxazole (75%), and ampicillin (69%), but little to no resistance to cefuroxime (0%), gentamicin (20%), and cefixime (24%). All imported batches were resistant to at least one antibiotic, with the strains from Belgium and Zambia exhibiting two and five different resistance profiles, respectively. This study demonstrates that the importation of chicks and fertilized eggs into the DRC can lead to the introduction of multidrug-resistant E. coli strains.