Introduction
Acinetobacter baumannii is the most common species within the Acinetobacter genus. It is a gram-negative, non-fermenting, coccobacillus bacterium with a genomic DNA (G+C) content ranging from 39% to 47% (Noor Alhuda & Mahmood, 2024; Wareth et al., 2019). Members of the Acinetobacter genus, belonging to the Moraxellaceae family, are widely distributed in various environments, such as soil, freshwater, oceans, and sediments (van der Kolk et al., 2019). A. baumannii is aerobic, non-motile, oxidase-negative, catalase-positive, indole-negative, and citrate-positive (AL-Juboori & Muhammad, 2025). This organism has emerged as a clinically significant pathogen due to its remarkable ability to acquire multidrug resistance (MDR) determinants and cause a wide range of infections in animals and humans. It is classified among the ESKAPE pathogens—Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, A. baumannii, Pseudomonas aeruginosa, and Enterobacter species—known for their ability to “escape” the effects of antibiotics and complicate treatment (Hussein & Mahdi, 2024). The global rise of MDR pathogens, including A. baumannii, has created an urgent need for alternative therapeutic strategies (Lafta & Sadeq, 2024). A. baumannii is associated with nosocomial infections, including meningitis, septicemia, endocarditis, and wound and burn infections (Sehree et al., 2023). Its pathogenicity is supported by multiple virulence factors, such as adhesion molecules, outer membrane proteins, biofilm formation, and iron acquisition mechanisms, enabling adherence to host tissues and evasion of immune responses (Momtaz et al., 2015; Peleg et al., 2008). In recent years, the prevalence of MDR A. baumannii has raised global public health concerns.
Studies have highlighted the presence of antibiotic resistance genes and antiseptic resistance, which reduce the effectiveness of treatment (Ghasemzadeh-Moghaddam et al., 2025). The emergence of plasmid-mediated resistance, such as colistin and fosfomycin resistance in Enterobacteriaceae and non-fermenting bacteria, illustrates the potential for horizontal transfer of resistance determinants (Falsafi et al., 2024). These findings underscore the importance of monitoring resistance profiles and the role of A. baumannii as a reservoir of clinically relevant resistance genes.
Moreover, natural compounds have been evaluated as potential alternatives for combating resistant pathogens. For instance, Leucas aspera leaf extracts exhibited antimicrobial and anti-inflammatory activities against MDR bacteria, reflecting interest in novel therapeutic approaches to tackle antimicrobial resistance (Sungar et al., 2024).
Despite extensive research on A. baumannii in human medicine, information regarding its distribution, virulence, and antimicrobial resistance in veterinary medicine is limited. Reports of A. baumannii in companion animals, including cats, are scarce, although its role in conjunctivitis and other infections has been suggested (van der Kolk et al., 2019). This gap highlights the necessity to study A. baumannii in veterinary settings, particularly in pet-associated infections, and to characterize its antimicrobial resistance and genetic determinants. Therefore, this study aimed to isolate and molecularly characterize A. baumannii from cases of conjunctivitis in cats in Baghdad Province, Iraq, and to determine the antimicrobial susceptibility profile of the recovered isolates.
Materials and methods
Sample collection and bacterial isolation
Conjunctival swabs were collected from 100 cats diagnosed with conjunctivitis, representing both sexes (48 females, 52 males) and different breeds: 22 Himalayan, 30 Sherazi, 23 Indigenous, 1 Siamese, 2 Scottish, 11 Persian, 6 British, 3 Calico, and 2 Angora. These samples were obtained from veterinary clinics located in three areas: Al-Dawrah, Al-Adhamiya, and Zayona, between November 2024 and March 2025. The specimens were transported to the laboratory using Amies transport media and cultured on selective A. baumannii media (HiCrome™ agar), blood agar, and MacConkey agar, and then incubated at 37 °C for 24 hours under aerobic conditions (Athanasiou, et al., 2018; Rebekah & Christie, 2023). All microbiological and molecular experiments were conducted at the Postgraduate Laboratory, Department of Microbiology, College of Veterinary Medicine, University of Baghdad, Baghdad, Iraq, ensuring accurate identification and further analysis of the isolates.
Identification
Cultural characteristics and microscopy
The cells were examined microscopically using oil immersion to observe the staining reaction and cell arrangement (Karen C & Patel, 2015).
Biochemical tests
A. baumannii Identification using conventional biochemical tests: oxidase test, urease test, motility test, oxidation–fermentation test (O-F test), catalase test (Jasim & Hayyawi, 2025), IMViC test (indole production test, methyl red test, Voges-Proskauer test, citrate utilization test), and triple sugar iron test (Hasso, 2018) were prepared according to previous studies (Fischbach & Dunning, 2009; MacFaddin, 2000). The VITEK2 compact system identified the suspected isolates and accurately identified each bacterial isolate with a 99% confidence level (Biomerieux, France).
Antimicrobial susceptibility test
Following the Kirby-Bauer method for assessing antibiotic susceptibility, five A. baumannii isolates were tested for their resistance against 10 discs for all classes of antibiotics Bioanalyse (Turkey) on Muller Hinton Agar, and were incubated at 37 °C for 24 hours. Antibiotics were chosen from the appropriate table of agents outlined in the relevant Clinical and Laboratory Standards Institute (CLSI) (Clinical and Laboratory Standards Institute, 2023) document for testing against Acinetobacter spp., emphasizing those suitable for use in veterinary medicine. The following antimicrobial agents were employed in the study: amikacin (30 μg), ampicillin-Sulbactam (10 μg), cefepime (30 μg), ceftazidime (30 μg), ceftriaxone (30 μg), ciprofloxacin (5 μg), colistin (10 μg), gentamycin (10 μg), levofloxacin (5 μg), and tobramycin (30 μg) (Lysitsas et al., 2023)especially during the last 30 years. Recent research in veterinary medicine also supports its emergence as an animal pathogen. However, relevant data are limited. In this study, we obtained 41 A. baumannii isolates from clinical samples of canine and feline origin collected in veterinary clinics in Greece between 2020 and 2023. Biochemical identification, antimicrobial susceptibility testing, molecular identification and statistical analysis were performed. Most of the samples were of soft tissue and urine origin, while polymicrobial infections were recorded in 29 cases. Minocycline was the most effective in vitro antibiotic, whereas high resistance rates were detected for almost all the agents tested. Notably, 20 isolates were carbapenem resistant and 19 extensively drug resistant (XDR).
Molecular identification
The molecular characterization of A. baumannii isolates was achieved through polymerase chain reaction (PCR), targeting the specific genes 16s rRNA and blaOXA-51-like (Qader, 2021).
DNA extraction
Genomic DNA was extracted using a commercially available purification kit from Favorgen Biotech Corp in Korea. The DNA retrieved from the A. baumannii isolates was assessed through spectrophotometric analysis, particularly utilizing a NanoDrop spectrophotometer (Razzaq, 2017).
Primers used to detect 16S rRNA and blaOXA-51-like
The primers utilized for identifying A. baumannii using PCR, specifically targeting these genes, are found in Table 1.
Amplification of blaOXA-51-like and 16S rRNA using PCR
A specific set of primers, detailed in Table 1, was employed to identify A. baumannii by targeting the blaOXA-51-like and 16S rRNA genes. DNA was extracted from A. baumannii, and a reaction mixture with a total volume of 25 µL was prepared for each gene. This mixture consisted of 1 µL of forward primer, 1 µL of reverse primer, and 5 µL of MasterMix. To reach the final volume of 25 µL, 1.5 µL of DNA was combined with 16.5 µL of nuclease-free water. The amplified fragments were subsequently separated using electrophoresis in a 1.5% agarose gel at 70 V for 2 hours. Finally, the fragments were stained with ethidium bromide and visualized under UV light. The PCR program was executed using a Thermal Block, as outlined in Table 2.
Statistical analysis
SPSS software, was used for data analysis. The chi-square test was used to find significant differences at P<0.05 and P<0.01.
Results
Isolation and identification of A. baumannii from cats suffering from conjunctivitis
Between November 2024 and March 2025, a total of 100 conjunctival samples were collected from cats of various breeds and both sexes presenting with conjunctivitis. A. baumannii was successfully isolated from 5 cases. All five isolates were confirmed through culture and conventional biochemical tests. Among these, the two isolates exhibiting the highest resistance to multiple antibiotics were further confirmed using PCR molecular detection, ensuring accurate identification at the genetic level.
Bacterial culturing and colony morphology
After transportation to the laboratory, the samples were cultured on selective media specific for A. baumannii. On HiCrome agar, the bacterial colonies appeared circular, convex, smooth, and translucent to opaque, with a light purple coloration surrounded by a halo, following 24 hours of incubation at 37 °C. On MacConkey agar, all five A. baumannii isolates exhibited pale, round, non-lactose fermenting colonies. On blood agar, the colonies appeared convex and grayish or whitish, with no evidence of hemolysis, indicating the absence of hemolysin enzyme activity.
Microscopic examination
The microscopic examination of the bacterial smears showed gram-negative coccobacilli grouped in pairs or singly.
Biochemical characterization
All five A. baumannii isolates tested positive for the catalase test, as evidenced by the formation of bubbles upon the addition of hydrogen peroxide (H2O2), while all were negative for the oxidase test. Furthermore, biochemical analyses revealed that none of the isolates produced indole, and both the Voges-Proskauer (VP) and methyl red (MR) tests yielded negative results. In contrast, all isolates showed positive results in the Simmons citrate test. Triple sugar iron (TSI) agar slants exhibited an alkaline over alkaline (K/K) reaction, indicating no glucose fermentation, along with the absence of gas and hydrogen sulfide (H2S) production. The urease test yielded negative results, as indicated by the yellow coloration of the medium. The sulfide-indole-motility (SIM) test was also negative for all isolates, confirming the absence of H2S production, indole formation, and bacterial motility. In the oxidative-fermentative (O/F) glucose test, the isolates only demonstrated oxidative metabolism, confirming their aerobic utilization of glucose.
Molecular diagnosis of isolates using blaOXA-51-like and 16S rRNA genes
The two A. baumannii isolates exhibiting the highest antimicrobial resistance were selected for sequencing. The partial sequences of the 16S rRNA gene were obtained using Sanger dideoxy sequencing. The resulting sequences were analyzed using the BLAST tool against the NCBI GenBank database to confirm species identity. Both sequences were submitted to and annotated in GenBank, receiving the following accession numbers: PQ269693.1 for isolate Ay.Sa.1 and PQ269694.1 for isolate Ay. Sa.2, thereby confirming the reliability of the biochemical tests. Additionally, the PCR results for the blaOXA-51-like gene indicated that this gene was present in both isolates identified as A. baumannii. These findings suggest that molecular diagnostics may offer a more accurate and sensitive detection method compared to HiCrome agar, Acinetobacter, and conventional biochemical tests.
Antimicrobial susceptibility testing
The antimicrobial resistance patterns of the isolates revealed worrisome trends. All five isolates (100%) were completely resistant to ceftazidime, cefepime, ceftriaxone, colistin, and ampicillin-sulbactam, showing no zone of inhibition around the antibiotic discs. Furthermore, 2 out of 5 isolates (40%) showed resistance to ciprofloxacin, tobramycin, gentamicin, amikacin, and levofloxacin. The inhibition zones for these antibiotics in the resistant isolates were below the Clinical and Laboratory Standards Institute (CLSI) (Clinical and Laboratory Standards Institute, 2023) interpretive criteria for susceptibility. Table 5 illustrates the resistance patterns in detail, confirming that a significant portion of the isolates were MDR.
This indicates the possible role of veterinary environments as reservoirs for resistant strains and the selective pressure exerted by overuse or misuse of antibiotics in pets.
Discussion
The detection of A. baumannii in 5% of feline conjunctivitis cases is a noteworthy epidemiological observation, underscoring the pathogen’s capacity to act as an opportunistic infectious agent in the ocular environment of companion animals. This finding aligns with prior investigations, such as those conducted by Holmström et al. (2022), who documented the presence of A.
baumannii in domestic animals, indicating its ecological versatility and ability to colonize non-human hosts. The observed colonial characteristics—namely, pale-to-pink colonies on HiCrome agar, lactose non-fermenting colonies on MacConkey agar, and the absence of hemolysis on blood agar—are consistent with standard morphological profiles previously described for A. baumannii (Alyais & Al-Shammary, 2024; Alshawi et al., 2019; Saikia et al., 2024). These phenotypic traits reinforce the reliability of conventional culturing techniques when coupled with accurate interpretation. Microscopically, the isolates were characterized as gram-negative, non-motile coccobacilli exhibiting catalase positivity and oxidase negativity—features that concur with taxonomic descriptions provided by previous research (Peleg et al., 2008; Abdulhussein & Mahdi, 2023). The biochemical profiles, including an alkaline slant/alkaline butt (K/K) reaction on TSI agar, and negative results for urease, indole, and motility, further validate the identity of the isolates as A. baumannii (Holmström et al., 2022; Lal et al., 2019). These results emphasize the diagnostic utility of phenotypic methods as a foundational step in bacterial identification.
To enhance diagnostic certainty, molecular confirmation was conducted using PCR assays targeting both the 16S rRNA gene and the intrinsic blaOXA-51-like carbapenemase gene. The detection of blaOXA-51-like, a chromosomally encoded gene highly conserved within A. baumannii serves as a robust molecular signature for species confirmation (Qader, 2021) and (Ewers et al., 2017). The integration of genotypic techniques strengthens diagnostic precision, especially in the context of MDR or phenotypically ambiguous isolates.
A. baumannii isolates recovered from feline conjunctivitis exhibited high levels of resistance to most tested antibiotics. Notably, 100% resistance was observed against ceftazidime, cefepime, ceftriaxone, ampicillin-sulbactam, and colistin, with highly significant P-values (P=0.0084). These findings reflect the global trend of A. baumannii becoming a MDR pathogen, particularly resistant to beta-lactams and polymyxins. These findings are in concordance with those of Lysitsas et al. (2023) who reported extensive resistance patterns in A. baumannii of animal origin, and also Leelapsawas et al. (2022) who associated antimicrobial overuse in veterinary practices with the propagation of resistant strains. Similar patterns were reported by other researchers (Hamidian & Nigro, 2019 ; Peleg et al., 2008) who highlighted the emergence of extended spectrum β-lactamases (ESBLs) and carbapenemases and resistance to last-line antibiotics in Acinetobacter baumannii clinical isolates.
Fluoroquinolones (ciprofloxacin and levofloxacin) and aminoglycosides (gentamycin, tobramycin, and amikacin) showed partial efficacy, with 60% of isolates being sensitive and 40% resistant (P=0.0392). This finding is supported by earlier research (Aliakbarzade et al., 2014). According to reports, resistance to older aminoglycosides is common, but amikacin remains more effective because it is less affected by aminoglycoside-modifying enzymes, like aacC1 and aphA6. The complete resistance to colistin, a last-resort antibiotic, is of particular concern. While earlier research (Li et al., 2006) reported preserved activity of colistin against A. baumannii, more recent research (Olaitan et al., 2014) reported emerging plasmid-mediated colistin resistance via mcr genes and lipid A modifications. This resistance threatens therapeutic outcomes in veterinary and human medicine alike. The variation in antibiotic responses (P<0.05) shows diverse resistance mechanisms among isolates, highlighting the necessity for improved diagnostics and careful antibiotic use. Partial sensitivity to amikacin and fluoroquinolones limits treatment options, making susceptibility testing vital. From a veterinary medicine perspective, ampicillin-sulbactam and gentamicin are considered first-line agents, whereas amikacin, tobramycin, fluoroquinolones, and advanced cephalosporins are regarded second-line and should be used restrictively. Importantly, colistin is classified as a last-resort antibiotic in human medicine and must not be applied in veterinary practice. This emphasizes the need for prudent antimicrobial stewardship to avoid further dissemination of resistant A. baumannii strains across animal and human populations
In regions, such as Iraq, where pet ownership is widespread and often unregulated, the implications of these findings are particularly consequential. The intimate cohabitation between humans and domestic animals increases the risk of interspecies transmission of MDR organisms. A. baumannii may act as a silent reservoir of resistance genes, with potential horizontal gene transfer to human-associated pathogens. This risk is exacerbated among immunocompromised individuals, children, and veterinary personnel. Therefore, these findings underscore the necessity for implementing structured antimicrobial stewardship programs, routine microbiological surveillance in veterinary clinics, and public education initiatives aimed at mitigating the threat of zoonotic antimicrobial resistance at the animal-human interface.
Conclusion
This study constitutes the first in-depth investigation of the isolation and molecular characterization of A. baumannii from conjunctivitis cases in domestic cats in Baghdad, Iraq. The results highlight the emergence of A. baumannii as a potential opportunistic ocular pathogen in felines, demonstrating its ability to colonize and persist in the conjunctival niche. The high levels of antimicrobial resistance observed, particularly to antibiotics commonly used in veterinary practice, underscore a significant threat posed by MDR strains in companion animals. These findings reinforce the urgent need for stricter antimicrobial stewardship in veterinary medicine, alongside ongoing surveillance and molecular tracking of resistance mechanisms. Furthermore, this study lays a foundation for future research exploring the zoonotic potential and environmental reservoirs of A. baumannii within domestic animal populations.
Ethical Considerations
Compliance with ethical guidelines
Ethical approval for this study was obtained from the Local Committee on Animal Care and Use at the College of Veterinary Medicine, University of Baghdad (Approval No.: 581). Participation in the study required prior informed consent from the cat owners, who were provided with a clear explanation of the study’s objectives. Verbal consent was also obtained before sample collection.
Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors.
Authors' contributions
Sample collection, diagnosis, experiments and writing the original draft: Ayat A. Hussein; Supervision, review and editing: Sahar M. Hayyawi.
Conflict of interest
The authors declared no conflict of interest.
Acknowledgments
The authors would like to express their sincere gratitude to the College of Veterinary Medicine, University of Baghdad, and express their special thanks to the Department of Microbiology for their valuable guidance and laboratory assistance throughout the research process.
References
Abdulhussein, N. M., & Mayaada, S. M. (2023). Molecular identification of virulence factors and genotyping of Acinetobacter baumannii isolated from clinical samples by ERIC-PCR. Iraqi Journal of Biotechnology, 22(1). [Link]
Abdul Razzaq, A. H., Al-Kubaisi, A. W. B., Aziz, L. M., & Hussain, A. S. (2017). Bacteriological and molecular study of Pseudomonas aeruginosa strains isolated from different clinical cases in Erbil and Kurkuk. The Iraqi Journal of Veterinary Medicine, 41(2), 124-130. [Link]
Aliakbarzade, K., Farajnia, S., Karimi Nik, A., Zarei, F., & Tanomand, A. (2014). Prevalence of Aminoglycoside resistance genes in Acinetobacter baumannii isolates. Jundishapur Journal of Microbiology, 7(10), e11924. [DOI:10.5812/jjm.11924] [PMID]
AL-Juboori, O. K., & Muhammad, S. J. (2025). Phenotypic and genotypic detection of biofilm formation, and capsular polysaccharide and relationship with antibiotic resistance of Acinetobacter baumannii isolated from different clinical sites in Salahdin city. Iraqi Journal of Biotechnology, 24(SI). [Link]
Ali Al-Shawi, I., Hasan Kadhum, S., & Mohammad Taher, E. (2019). Molecular study of Acinetobacter baumannii isolated from skin infection. Al-Kufa University Journal for Biology, 11(1), 107-118. [DOI:10.36320/ajb/v11.i1.8033]
ALYais, Z. H., & Al-Shammary, A. H. (2024). Dynamic Patterns of Acinetobacter baumannii Recovered from Local Dairy Chain and Human UTI cases in Baghdad. Diyala Journal for Veterinary Sciences, 2(2), 23–38. [DOI:10.71375/djvs.2024.02202]
Athanasiou, L. V., Psemmas, D. E., & Papaioannou, N. (2018). Conjunctival cytology assessment in dogs and cats: Sampling, diagnostic techniques and findings. Journal of the Hellenic Veterinary Medical Society, 69(1), 701–712. [DOI:10.12681/jhvms.16382]
Clinical and Laboratory Standards Institute. (2023). Performance standards for antimicrobial susceptibility testing (33rd ed., CLSI supplement M100). Wayne (PA): Clinical and Laboratory Standards Institute. [Link]
Ewers, C., Klotz, P., Leidner, U., Stamm, I., Prenger-Berninghoff, E., & Göttig, S., et al. (2017). OXA-23 and ISAba1-OXA-66 class D β-lactamases in Acinetobacter baumannii isolates from companion animals. International Journal of Antimicrobial Agents, 49(1), 37–44. [DOI:10.1016/j.ijantimicag.2016.09.033] [PMID]
Falsafi, S., Ghasemian, A., Kohansal, M., Zarenezhad, E., Shokouhi Mostafavi, S. K., & Rezaian, M., et al. (2024). Plasmid-mediated colistin and fosfomycin resistance among clinical isolates of ESBL- and carbapenemase-producing Klebsiella pneumoniae in Northern Iran. Archives of Razi Institute, 79(4), 881–888. [DOI:10.32592/ari.2024.79.4.881] [PMID]
Fischbach, F. T., & Dunning, M. B. (2009). A manual of laboratory and diagnostic tests. Philadelphia: Lippincott Williams & Wilkins. [Link]
Ghasemzadeh-Moghaddam, H., Radmeher, M., Firouzeh, N., Moghbeli, M., Azimian, A., & Salehi, M., et al. (2025). Emerging Challenges: High frequency of Antiseptic Resistance Encoding Genes and Reduced Biguanide Susceptibility in Antibiotic-Resistant Acinetobacter baumannii in Iran. Archives of Razi Institute, 80(1), 243–248. [DOI:10.32592/ari.2025.80.1.243] [PMID]
Gunn-Christie, R. G. (2024). Collection and submission of laboratory samples from animals. In MSD Veterinary Manual. Merck & Co., Inc. [Link]
Hamidian, M., & Nigro, S. J. (2019). Emergence, molecular mechanisms and global spread of carbapenem-resistant Acinetobacter baumannii. Microbial Genomics, 5(10), e000306. [DOI:10.1099/mgen.0.000306] [PMID]
Hasso, S. A. (2018). Epidemiological study of thermophlic Campylobacter isolated from diarrheic and non diarrheic cows in Baghdad governorate: Abdulameer Jawad Aldrajii 1 and Saleem Amin Hasso2. The Iraqi Journal of Veterinary Medicine, 42(1), 105-113. [DOI:10.30539/iraqijvm.v42i1.39]
Holmström, T. C. H., David, L. A., Motta, C. C., Rocha-de-Souza, C. M., Maboni, G., & Coelho, I. S., et al. (2022). Acinetobacter calcoaceticus-Acinetobacter baumannii complex in animals: Identification and antimicrobial resistance profile. Pesquisa Veterinária Brasileira, 42, Article e07043. [DOI:10.1590/1678-5150-PVB-7043
Hussein, S. H., & Mahdi, M. S. (2024). Molecular detection of arr2 gene of rifampcin resistant Acinetobacter baumannii isolated from patients referring Baghdad hospitals. Iraqi Journal of Biotechnology, 23(1). [Link]
Jasim, S., & Hayyawi, S. M. (2025). Isolation and detection of biofilm producing Pseudomonas aeruginosa from suspected urinary tract infections in dogs and its resistance to antibiotics. The Iraqi Journal of Veterinary Medicine, 49(1), 45-54. [Link]
Karen, C. C., & Patel, J. B. (2015). Standard procedures for microbiological identification. In Manual of Clinical Microbiology. Washington: ASM Press. [Link]
Lafta, I. J., & Sadeq, Z. (2024). Pseudomonas aeruginosa is an effective indicator for screening of quorum sensing inhibition by plant extracts. The Iraqi Journal of Veterinary Medicine, 48(1), 54–62. [Link]
Lal, S., Yadav, A., & Khare, R. (2019). Phenotypic and genotypic characterization of Acinetobacter spp. from clinical samples. Journal of Laboratory Physicians, 11(2), 116–121.
Leelapsawas, C., Yindee, J., Nittayasut, N., Chueahiran, S., Boonkham, P., & Suanpairintr, N., et al. (2022). Emergence and multi-lineages of carbapenemase-producing Acinetobacter baumannii-calcoaceticus complex from canine and feline origins. The Journal of Veterinary Medical Science, 84(10), 1377–1384. [DOI:10.1292/jvms.22-0276] [PMID]
Li, J., Rayner, C. R., Nation, R. L., Owen, R. J., Spelman, D., & Tan, K. E., et al. (2006). Heteroresistance to colistin in multidrug-resistant Acinetobacter baumannii. Antimicrobial Agents and Chemotherapy, 50(9), 2946–2950. [DOI:10.1128/aac.00103-06] [PMID]
Lysitsas, M., Triantafillou, E., Chatzipanagiotidou, I., Antoniou, K., & Valiakos, G. (2023). Antimicrobial Susceptibility Profiles of Acinetobacter baumannii Strains, Isolated from Clinical Cases of Companion Animals in Greece. Veterinary Sciences, 10(11), 635. [DOI:10.3390/vetsci10110635] [PMID]
MacFaddin, J. F. (2000). Biochemical tests for identification of medical bacteria. Philadelphia: Williams and Wilkins. [Link]
Momtaz, H., Seifati, S. M., & Tavakol, M. (2015). Determining the prevalence and detection of the most prevalent virulence genes in Acinetobacter Baumannii isolated from hospital infections. International Journal of Medical Laboratory, 2(2), 87-97. [Link]
Noor Alhuda A. K, & S. S Mahmood. (2024). The prevalence of (ompa, csue) genes among biofilm producer acinetobacter baumannii isolates. Iraqi journal of Agricultural Sciences, 55(5), 1720-1727. [DOI:10.36103/c5bw0g67]
Olaitan, A. O., Morand, S., & Rolain, J. M. (2014). Mechanisms of polymyxin resistance: Acquired and intrinsic resistance in bacteria. Frontiers in Microbiology, 5, 643. [DOI:10.3389/fmicb.2014.00643] [PMID]
Peleg, A. Y., Seifert, H., & Paterson, D. L. (2008). Acinetobacter baumannii: Emergence of a successful pathogen. Clinical Microbiology Reviews, 21(3), 538–582. [DOI:10.1128/cmr.00058-07] [PMID]
Qader, M. (2021). Molecular study of Acinetobacter baumannii using 16S rRNA and bla OXA-51 gene isolated from hospitals in Duhok-Kurdistan Region, Iraq. Journal of University of Duhok, 24(1), 19–25. [DOI:10.26682/sjuod.2021.24.1.3]
Saikia, S., Gogoi, I., Oloo, A., Sharma, M., Puzari, M., & Chetia, P. (2024). Co-production of metallo-β-lactamase and OXA-type β-lactamases in carbapenem-resistant Acinetobacter baumannii clinical isolates in North East India. World Journal of Microbiology & Biotechnology, 40(6), 167. [DOI:10.1007/s11274-024-03977-1] [PMID]
Sungar, S., Toragall, M. M., Abdul Mujeeb, M., Puranik, S. I., Akbar, A. A., Aladkatti, R. H., & Ghagane, S. C. (2024). Phytochemical analysis, antimicrobial and anti-inflammatory efficacy of Leucas aspera Leaf extracts. Archives of Razi Institute, 79(4), 761–768. [DOI:10.32592/ari.2024.79.4.761] [PMID]
van der Kolk, J. H., Endimiani, A., Graubner, C., Gerber, V., & Perreten, V. (2019). Acinetobacter in veterinary medicine, with an emphasis on Acinetobacter baumannii. Journal of Global Antimicrobial Resistance, 16, 59–71. [DOI:10.1016/j.jgar.2018.08.011] [PMID]
Wareth, G., Neubauer, H., & Sprague, L. D. (2019). Acinetobacter baumannii–a neglected pathogen in veterinary and environmental health in Germany. Veterinary Research Communications, 43(1), 1-6. [DOI:10.1007/s11259-018-9742-0]
