Bacterial Detection and Antimicrobial Susceptibility Profiling in a Broiler Breeder Flock
,
Abstract
Background: The health of breeders is essential for the next generation of chicks. Bacterial agents, such as Escherichia coli, Salmonella enterica and Mycoplasma gallisepticum or Mycoplasma synoviae, are the leading causes of disease and mortality in breeder poultry. The widespread usage of antimicrobials in poultry, has raised concerns about the potential for spread of antimicrobial resistance. The present study aimed to identify bacterial infections and antibiotic resistance patterns in the case of breeder’s mortality.
Methods: Samples were collected from tissues and bone marrow of sixteen broiler breeders. The specimens were cultured onto blood agar, MacConkey agar and confirmatory biochemical media for the bacteriological examination. Sabouraud dextrose agar was used for fungal isolation. The specimens were cultured on Mueller-Hinton agar to assess their antibiotic resistance to gentamicin, ceftriaxone, tetracycline, penicillin, erythromycin, streptomycin, lincomycin, and amoxicillin
Results: The bacteria including Escherichia coli (93.8%), Staphylococcus (31.3%), Streptococcus (12.5%), Bacillus (12.5%) and Clostridium (6.3%) were isolated. Co-infection was observed in 50% of carcasses, most frequently involving E. coli and Staphylococcus. Isolates from 62.5% were resistant to all the antibiotics tested. Gentamicin was the most effective antibiotic.
Conclusion: Escherichia coli was the dominant isolate, and its detection in the bone marrow of 31.3% of cases confirms systemic dissemination. Consequently, enhanced biosecurity protocols are essential to prevent the spread of pathogens such as E. coli. Antimicrobial susceptibility testing revealed a multidrug-resistant pattern. Therefore, poultry farms should base antibiotic selection on specific laboratory results rather than relying on empirical broad-spectrum therapy.
2. Joseph J, Zhang L, Adhikari P, et al. Avian Pathogenic Escherichia coli (APEC) in Broiler Breeders: An Overview. Pathogens 2023; 12(11):1280.
3. Ghahramani Z, Mosleh N, Shomali T, et al. A study on selected responses and immune structures of broiler chickens with experimental colibacillosis with or without florfenicol administration. BMC Vet Res 2024; 20(1):371.
4. Murray CE, Varga C, Ouckama R, et al. Temporal study of Salmonella enterica serovars isolated from environmental samples from ontario poultry breeder flocks between 2009 and 2018. Pathogens 2023; 12(2):278.
5. Shoaib M, Riaz A, Hassan M, et al. Sero-prevalence and associated risk factors of Mycoplasma gallisepticum, Mycoplasma synoviae and Salmonella pullorum/gallinarium in poultry. Pak Vet J 2019; 40:253-6.
6. Matos M, Mitsch P, Liebhart D, et al. Co-Infection of Chickens with Staphylococcus lentus and Staphylococcus aureus from an Outbreak of arthritis, synovitis, and osteomyelitis argues for detailed characterisation of isolates. Animals 2024; 14(17):2574.
7. Ansari F, Bokaie S, Peighambari SM, et al. Survey of Salmonella infections in broiler farms in Iran during 2013-2014: a cross-sectional study. Iran J Microbiol 2020; 12(5):404-10.
8. Randall LP, Cooles SW, Coldham NC, et al. Modification of enrofloxacin treatment regimens for poultry experimentally infected with Salmonella enterica serovar typhimurium dt104 to minimize selection of resistance. Antimicrob Agents Chemother 2006; 50(12):4030-7.
9. Nemati M, Hermans K, Lipinska U, et al. Antimicrobial resistance of old and recent Staphylococcus aureus isolates from poultry: first detection of livestock-associated methicillin-resistant strain st398. Antimicrob Agents Chemother 2008; 52(10):3817-9.
10. Bhattarai RK, Basnet HB, Dhakal IP, et al. Antimicrobial resistance of avian pathogenic Escherichia coli isolated from broiler, layer, and breeder chickens. Vet World 2024; 17(2):480-99.
11. Kim SW, Kim K, Lee YJ. Comparative analysis of antimicrobial resistance and genetic characteristics of Escherichia coli from broiler breeder farms in Korea. Can J Animal Sci 2022; 102(2):342-51.
12. Talebiyan R, Kheradmand M, Khamesipour F, et al. Multiple antimicrobial resistance of Escherichia coli isolated from chickens in Iran. Vet Med Int 2014; 2014:491418.
13. Watts A, Wigley P. Avian Pathogenic Escherichia coli: An overview of infection biology, antimicrobial resistance and vaccination. Antibiotics 2024; 13(9):809.
14. Sun H, Liu P, Nolan LK, et al. Avian pathogenic Escherichia coli (APEC) infection alters bone marrow transcriptome in chickens. BMC Genom 2015; 16(1):690.
15. Alfifi A, Christensen JP, Hounmanou YMG, et al. Characterization of Escherichia coli and other bacteria isolated from condemned broilers at a Danish abattoir. Front Microbiol 2022; 13:1020586.
16. Chadfield M, Christensen J, Christensen H, et al. Characterization of streptococci and enterococci associated with septicaemia in broiler parents with a high prevalence of endocarditis. Avian Pathology 2004; 33(6):610-7.
17. Becker K, Skov RL, von Eiff C. Staphylococcus, Micrococcus, and other catalase‐positive cocci. Manual Clin Microbiol 2015:354-82.
18. Park S, Ronholm J. Staphylococcus aureus in agriculture: lessons in evolution from a multispecies pathogen. Clin Microbiol Rev 2021; 34(2):10.1128/cmr. 00182-20.
19. Zuo Z, Li Q, Guo Y, et al. Feed-borne Bacillus cereus exacerbates respiratory distress in chickens infected with Chlamydia psittaci by inducing haemorrhagic pneumonia. Avian Pathology 2020; 49(3):251-60.
20. Haque MA, Wang F, Chen Y, et al. Bacillus spp. contamination: a novel risk originated from animal feed to human food chains in south-eastern Bangladesh. Front Microbiol 2022; 12:783103.
21. Hustá M, Tretiak S, Ducatelle R, et al. Clostridium perfringens strains proliferate to high counts in the broiler small intestinal tract, in accordance with necrotic lesion severity, and sporulate in the distal intestine. Vet Microbiol 2023; 280:109705.
22. Crespo R, Franca M, Shivaprasad H. Ulcerative enteritis-like disease associated with Clostridium sordellii in quail. Avian Dis 2013; 57(3):698-702.
23. Adah B, Kwanashie C, Ameh J. Isolation and characterization of yeast associated with hatchery dead-in-shell embryos in Zaria. J Agriculture Vet Sci 2015; 9(1):12-7.
24. Wu Z, Ding L, Bao J, et al. Co-infection of Mycoplasma gallisepticum and Escherichia coli triggers inflammatory injury involving the IL-17 signaling pathway. Front Microbiol 2019; 10:2615.
25. Abdelaziz AM, Mohamed MH, Fayez MM, et al. Molecular survey and interaction of common respiratory pathogens in chicken flocks (field perspective). Vet World 2019; 12(12):1975.
26. Aberkane C, Messaï A, Messaï CR, et al. Antimicrobial resistance pattern of avian pathogenic Escherichia coli with detection of extended-spectrum β-lactamase-producing isolates in broilers in east Algeria. Vet World 2023; 16(3):449-54.
27. Roth N, Käsbohrer A, Mayrhofer S, et al. The application of antibiotics in broiler production and the resulting antibiotic resistance in Escherichia coli: A global overview. Poultry Sci 2019; 98(4):1791-804.
28. Mehdi Y, Létourneau-Montminy MP, Gaucher ML, et al. Use of antibiotics in broiler production: Global impacts and alternatives. Animal Nut 2018; 4(2):170-8.
| Files | ||
| Issue | Vol 14 No 1 (2026) | |
| Section | Original Articles | |
| Keywords | ||
| Antimicrobial resistance Bacterial infection Broiler breeder Escherichia coli. | ||
| Rights and permissions | |
|
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
