Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2021.193.198NnajiJ.O. MosesI.B. EjikeugwuP.C. NwakaezeE.A. Ude-UdeI. IrohaI.R. 22021242Background and Objective: The global antibiotic resistance threat posed by ESBL and AmpC-producing Gram-Negative Bacteria (GNB) is a public health menace that rolls back the gains of ‘One Health’. This study investigated the antibiogram and prevalence of AmpC and ESBL genes in Escherichia coli, Klebsiella spp. and Pseudomonas spp. from poultry and abattoir milieus in Enugu and Ebonyi States, Nigeria. Materials and Methods: Isolation, identification and characterization of GNBfrom samples (150 abattoirs and 300 poultry) were done using standard microbiological techniques. Antimicrobial Susceptibility Testing (AST), as well as phenotypic screening for ESBL and AmpC enzymes, was performed using the Kirby-Bauer disc diffusion technique. PCR technique was used to screen isolated GNB for AmpC and ESBL genes. Results: Exactly 42 E. coli and 8 Klebsiella spp. isolate from poultry samples and another 5 P. aeruginosa isolates from abattoir samples were phenotypically confirmed to be ESBL-producers. AmpC enzymes were phenotypically detected in 8 E. coli and 13 P. aeruginosa isolates from poultry samples. All ESBL and AmpC-positive bacteria exhibited high resistance frequencies to tested antibiotics, especially to the carbapenems and cephalosporins. ESBL genes (CTX-M, SHV-1, TEM) and AmpC genes (ACC-M, MOX-M, DHA-M) were harbored by the isolated GNB in this study. Overall, the DHA-M and CTX-M genes, mediating AmpC and ESBL production respectively were the most prevalent genes harbored by the tested GNB. Conclusion: This study reported that AmpC and ESBL genes are harbored by Gram-negative bacteria (E. coli, Klebsiella species and P. aeruginosa) that emanated from poultry and abattoir milieus.]]>Jacoby, G.A. and L.S. Munoz-Price,2005352380391Bush, K., G.A. Jacoby and A.A. Medeiros,19953912111233Zhang, C.H., Y.L. Liu and J.H. Wang,2010Escherichia coli isolated in Henan, China.]]>920302034Zurfluh, K., H. Hächler, M. Nüesch-Inderbinen and R. Stephan,2013Enterobacteriaceae isolates from rivers and lakes in Switzerland.]]>7930213026Zhu, B., P. Zhang, Z. Huang, H.Q. Yan, A.H. Wu, G.W. Zhang and Q. Mao,2013Pseudomonas aeruginosa plasmid-mediated AmpC β-lactamase.]]>7664668Fernandez, M., S. Conde, J. Torre, C. Molina-Santiago, J.L. Ramos and E. Duque,2012Pseudomonas putida KT2440.]]>5610011009Franco, M.R., H.H. Caiaffa-Filho, M.N. Burattini and F. Rossi,2010Pseudomonas aeruginosa in a Brazilian university hospital.]]>65825829Bush, K. and G.A. Jacoby,201054969976Cheesbrough, M.,20001st Edn.,pp: 132-143pp: 132-143Clinical Laboratory Standard Institute (CLSI), 20112011Chika, E., I. Ifeanyichukwu, U. Malachy, O. Benigna and E.C. Adaora et al.,2016Klebsiella spp. isolated from abattoir.]]>4117121Iroha, I.R., E.S. Amadi, A.E. Oji, A.C. Nwuzo and P.C. Ejike-Ugwu,201037783Kolar, M., J. Bardon, M. Chroma, K. Hricova, T. Stosova, P. Sauer and D. Koukalova,2010Enterobacteriaceae in poultry in the Czech Republic.]]>55119124Iroha, I.R., M.U. Adikwu, E.S. Amadi, I. Aibinu and C.O. Esimone,2008E. coli from secondary and tertiary hospital in South Eastern Nigeria.]]>3514519Motayo, B.O., P.A. Akinduti, F.A. Adeyakinu, P.O. Okerentugba and J.C. Nwanze et al.,2013Escherichia coli and Klebsiella pneumoniae in Abeokuta, South western, Nigeria.]]>1310911097Yilmaz, N.O., N. Agus, E. Bozcal, O. Oner and A. Uzel,2013Escherichia coli and Klebsiella pneumoniae.]]>315359Mansouri, S., D.K. Neyestanaka, M. Shokoohi, S. Halimi, R. Beigverdi, F. Rezagholezadeh and A. Hashemi,2014Klebsiella pneumoniae and Escherichia coli producing Extended Spectrum β-lactamases in Kerman, Iran.]]>2014Jacoby, G.A.,200922161182Walsh, T.R., M.A. Toleman, L. Poirel and P. Nordmann,200518306325Thomson, K.S.,20104810191025Kanu, A.M., N. Mgbajiaka and N. Abadom, 20162016Manchanda, V. and N.P. Singh, 200351415418