Aceh Journal of Animal Science (2022) 7 (2): 34-40 Aceh Journal of Animal Science Journal homepage: www.jurnal.unsyiah.ac.id/AJAS * Corresponding author. Email address: andymunengwa@gmail.com Printed ISSN 2502-9568; Electronic ISSN 2622-8734 This is an open access article under the CC - BY 4.0 license (https://creativecommons.org/licenses/by/4.0/) Susceptibility profile of Zimbabwean livestock fecal Escherichia coli isolates to veterinary antibiotics: Implications for standardization of antimicrobial resistance surveillance in livestock production Munengwa Anderson * , Chikumba Nation, Mugoti Alban, Dziwanyika Lenin Department of Animal Production Sciences and Health, Marondera University of Agricultural sciences and Technology. ARTICEL INFO ABSTRACT Keywords: Antibiotic Resistance Pigs Poultry Beef Cattle Escherichia coli Received: 21 September 2021 Accepted: 14 February 2022 Available online: 30 June 2022 DOI: 10.13170/ajas.7.2.22766 Susceptibility patterns of Escherichia coli to Veterinary Critically Important Antimicrobials (VCIAs) are poorly understood in most developing countries. We determined those patterns on n = 180 livestock fecal isolates from Chikomba district by disk diffusion method. Multiple Antibiotic Resistance (MAR) indices for the isolates were determined for risk analysis. Chi-square was used to test how antibiotic susceptibility level associated with animal species and farming scale. Resistance to Tetracycline and Ampicillin was high across animal species (above 70%). Moderate levels of resistance (30% to 54%) to Erythromycin, Trimethoprim and Chloramphenicol were detected across livestock species. Resistance levels were low (below 30 %) for Ciprofloxacin and Gentamicin. Resistance to Gentamicin, Tetracycline, Ciprofloxacin, Ampicillin, Chloramphenicol and Ceftazidime was associated with animal species (P ˂ 0.05). Antibiotic susceptibility patterns were independent of farming scale (P > 0.05). Frequencies of isolates within each risk zone depended on animal species (P ˂ 0.05), contrary to farming systems (P > 0.05). Multi-Drug Resistance was 73%, where most isolates were resistant to 5 antibiotics (23%) and none exhibited resistance to all antibiotics. Only 55% of isolates from cattle and over 80% from pigs and layers were within the high risk zone. Twenty nine of the isolates were extended spectrum beta lactamase (ESBL) positive. Higher ESBL frequencies (44%) were observed within Large Scale Commercial Farms (LSCF) followed by for Small Scale Commercial Farms (SSCF) (25%) and Resettlement farms (A1) (14%). Similarly, ESBL prevalence varied by livestock species (P> 0.05), as follows: pig (39%), layers (32%) and beef (12%). Our study suggests high incidences of multi-drug resistance in livestock which need AMR surveillance strategies. Introduction Escherichia coli are gram-negative bacteria that inhabit the guts of many animals. There is much documented work on the incidences of resistance of such bacteria to antimicrobial agents (Founou et al., 2018; Raiz et al., 2011). This tendency is enhanced by their potential to produce Extended Spectrum Beta Lactamase (ESBL) enzymes which can hydrolyze beta lactam derived antibiotics such as Penicillins, Cephalosporins and Aztreonam (Massot et al., 2017; Trot, 2013). As a result of this, Escherichia coli often exhibit multi-drug resistance characteristics, rendering antibiotics ineffective in treating disease conditions (Massot et al., 2017; Rossolini et al., 2007; O’Neill, 2015). Notwithstanding this, animal health is faced with challenges of limited drug alternatives in the treatment of conditions as a result of exposure to these bacteria. Given the high incidences of Escherichia coli diseases such as Colibacilosis, the sustainability of the livestock production sector will under serious threat. Increased antimicrobial use, particularly in livestock production has been reported to be the major cause of antimicrobial resistance (AMR), worldwide (Landers et al., 2012; O’Neill, 2015; Tiseo et al., 2020). Such antimicrobial agents are normally