Skip to main content
Download PDF
  • Research note
  • Open access
  • Published:

Prevalence and antimicrobial resistance profiles of Salmonella species and Escherichia coli isolates from poultry feeds in Ruiru Sub-County, Kenya

BMC Research Notes volume 14, Article number: 41 (2021) Cite this article

Abstract

Objectives

Contaminated poultry feeds can be a major source of E. coli and Salmonella infections in poultry. This study aimed at determining microbial load, prevalence and antimicrobial resistance profiles of Salmonella sp. and E. coli and associated resistance genes among isolates from poultry feeds.

Results

A total of 150 samples of different poultry feed types were randomly collected from selected sites within Ruiru Sub-County. The microbial load was determined, Salmonella sp. and Escherichia coli were isolated and antimicrobial susceptibility test carried out. Antimicrobial resistance genes were also screened among the resistant isolates. Out of analyzed samples, 58% and 28% contained Escherichia coli and Salmonella sp. respectively. Bacterial load ranged between 3.1 × 105 and 3.0 × 106 cfu/g. Highest resistance was against ampicillin (41%) for Salmonella sp. and (62%) for E. coli isolates. Ampicillin resistant isolates carried TEM and SHV genes. In addition, strB and Dfr resistance genes associated with streptomycin and cotri-moxazole were detected. All the isolates were susceptible to chloramphenicol and ciprofloxacin. The study reveals high bacterial contamination, presence of beta-lactamase, aminoglycoside and sulphonamide resistance genes across isolates from poultry feeds. Therefore, contaminated poultry feeds with bacteria are likely to lead to increase in antimicrobial resistant strains across the community.

Introduction

Poultry feeds are contaminated with microbes during harvesting, preparation and sale of the produced feeds [1]. Poultry feed contamination has been associated with Escherichia coli and Salmonella species [2]. Antimicrobial resistance is a concern with medical and veterinary sciences due to its effects on public health [3]. Indiscriminate use of antimicrobials may increase antibiotic resistance in nonpathogenic and pathogenic bacteria [4].

Antibiotics, enzymes, pigments and antifungals are non-nutritive additives in feed formulations that help in maintaining health status of the poultry [5, 6]. The intensive use of antibiotics in poultry production [7] has led to antibiotic resistance in almost all common class of antibiotics [8]. Antibiotics in poultry promote growth, treat, control, and prevent infectious diseases [5, 9, 10]. However, the beneficial uses of antibiotics in poultry have been affected by emergence of resistant strains of bacteria [11]. Different studies have been carried out to determine the existence of Salmonella and E. coli in domestic fowl feeds and antibiotic resistance patterns on isolates from poultry feed [12,13,14]. Nonetheless, measures to control use of antibiotics in food animals and investigations on associated resistant genes in poultry feed are minimal in developing countries.

In Kenya, increased poultry rearing has increased the demand for feeds leading to more feed companies. Microbiological health controls during preparation of poultry feeds are important to minimize contamination of poultry feeds [15]. However, there are minimal reports on bacterial load, profiles of antimicrobial resistance, associated resistance genes and potential source of Salmonella and E. coli contamination in poultry feeds in Kenya.

This research determined the bacterial load, prevalence of Salmonella sp. and Escherichia coli, the antimicrobial resistance patterns and assessed presence of resistance genes in poultry feed in Ruiru Sub-County Kenya.

Main text

Methods

Sampling

A cross-sectional study was carried out between January and April 2019. A total of 150 poultry feed samples was picked up randomly from selected outlets in Biashara, Gitothua, Gatong’ora, Kiuu and Mwihoko in Ruiru Sub County, Kenya. Different types of poultry feed that had been produced recently were selected; these included grower mash, layer mash, starter mash, finisher mash, kienyeji mash, chick mash, maize germ and sunflower. Estimated 400 g of each sample was collected aseptically in collection bags and taken to Kenyatta University Microbiology laboratory for analysis.

Before commencement of this study, permission was sort and granted from Commissions for Science Technology and Innovation and County Commissioner, Kiambu County.

Bacteriological analysis

One gram of feed sample was homogenized in 9 ml sterile deionized water, thoroughly mixed to form a ratio of 1:10 and a fourfold serial dilutions were made. Aliquot of 0.1 ml of the serial dilution was drawn and inoculated into nutrient agar (Oxoid) using the spread plate method. The inoculants were then incubated at 37 °C for 18–24 h. Colonies were counted using colony counter and total bacterial count calculated; CFU/g = level of Dilution plated x number of colonies counted/ amount plated [16]. Bacterial counts below 30 and above 300 were excluded since they were not within the statistically proven range of colonies to be considered when determining total count of bacteria [17].

Isolation and identification of Salmonella sp. and Escherichia coli

Samples were enriched in selenite F broth and peptone water (Oxoid) and incubated at 37 °C for 18 h. Thereafter, Samples enriched in selenite F broth were inoculated onto Xylose Lysine Deoxycholate (XLD) agar and Salmonella-Shigella (SS) agar (Oxoid) for selection of Salmonella sp. Samples enriched in peptone water were inoculated onto sorbitol MacConkey agar (Oxoid). The inoculated cultures were then incubated at 37 °C for 24 h and biochemical tests employed to confirm suspected Salmonella sp. and Escherichia coli as previously described [18, 19].

Antimicrobial susceptibility test

Kirby–Bauer disc diffusion technique was applied to establish the susceptibility of isolates to antibiotics [20]. Antimicrobial agents; ampicillin (10 µg), ceftriaxone (30 µg), co-trimoxazole (25 µg), tetracycline (30 µg), chloramphenicol (50 µg), ciprofloxacin (30 µg) (Oxoid) were evaluated using Escherichia coli ATCC 25,922 as control organism. Antimicrobial susceptibility results were elucidated according to Clinical and Laboratory Standard Institute guidelines [21].

Extraction of bacteria genomic DNA

Bacteria DNA was extracted using boiling method as earlier described [22, 23]. One milliliter of overnight bacterial culture of the pooled 34 bacterial resistant isolates were suspended in 1000 μl of sterile distilled water and then boiled for 18 min at 100 °C. The resulting suspension was then centrifuged for 5 min at 14,200 rpm to sediment the debris and the supernatant was stored at − 20 °C for subsequent use as the DNA template.

Amplifications of drug associated resistance genes

Resistance genes encoding resistance to betalactams; SHV (sulphydryl variable enzyme), TEM (temoneira), sulpnomide; Dfr (dihydroflavonol 4-reductase enzyme), aminoglycoside; strB (streptomycin) genes were assessed as previously described [19, 20]. Escherichia coli ATCC 25922 known to carry different antimicrobial resistance genes was used as the positive control. Polymerase Chain Reaction amplification products were validated by visualization using gel electrophoresis as previously described [24].

Data analysis

The prevalence was calculated as positive samples as a percentage of total samples collected. Data on antimicrobial resistance was interpreted as resistant, intermediate or susceptible. Analysis of variance was used to determine the variability of bacterial loads among the samples and Tukey’s HSD at a significance of 0.05 was used to separate the means.

Results

Microbial load in poultry feeds

A total of 150 samples were analyzed including layer mash, grower mash, chick mash, kienyeji mash, starter mash, finisher mash and maize germ/sunflower. Thirty seven samples were excluded since their colony count was not within the required range of 30–300 colonies. Bacterial load ranged from 3.1 × 105 to 3.0 × 106 cfu/g. The highest bacterial load was detected in layer mash (Table 1). There was a significant difference in bacterial load among the poultry feeds (p = 0.0001).

Table 1 Range of bacterial load in poultry feeds
Full size table

Prevalence of Salmonella sp. and E. coli

Out of the 150 samples, 58% were detected with Escherichia coli and 28% with Salmonella sp. The prevalence of Salmonella sp. in different poultry feeds ranged from 17 to 38% while the prevalence of Escherichia coli was between 33 and 100% among the different types of poultry feeds (Table 2).

Table 2 Prevalence of Salmonella sp. and Escherichia coli in different poultry feed
Full size table

Antimicrobial susceptibility profiles for Salmonella sp. and Escherichia coli

The Salmonella sp. showed diverse response to different antibiotics used. All Salmonella sp. were susceptible to ciprofloxacin, chloramphenicol and streptomycin. However, among the tested isolates, 41% were resistant to ampicillin, 2% to co-trimoxazole, 5% to ceftriaxone and tetracycline. Intermediate ranged between 0 and 19% (Table 3).

Table 3 Antimicrobial susceptibility profiles of Salmonella sp.
Full size table

Escherichia coli isolates showed highest resistance against ampicillin (71%). Resistance to other antibiotics ranged from 1 to 10% with no isolate showing resistance to ciprofloxacin. Escherichia coli isolates were 100% susceptible to ciprofloxacin, followed by chloramphenicol (98%), co-trimoxazole (89%), tetracycline and streptomycin (86%) and ceftriaxone (78%). The highest intermediate was observed in ampicillin with 21% (Additional file 1: Table S1).

Antimicrobial resistance genes among the isolates

The total number of isolates screened for resistance genes was 34. Among the screened isolates, TEM, SHV, Dfr and strB genes were detected (Additional file 2: Figure S1, Additional file 3: Figure S2, Additional file 4: Figure S3, Additional file 5: Figure S4). The TEM gene dominated with 24%, followed by Dfr 21%, SHV 12% and strB 9% (Additional file 6: Table S2).

Discussion

The recorded prevalence of 28% of Salmonella sp. in poultry feeds was similar to previous prevalence of 29% of Salmonella isolates reported in Tanzania [25] and Bangladesh [26]. Nevertheless, studies in Africa have continued to show varying results on prevalence of Salmonella in poultry feeds. A prevalence of 38% and 31% was reported in Nigeria [27, 28] and a prevalence of 71%, 55% and 29% in Bangladesh [15, 19, 26]. The prevalence of Salmonella sp. from different poultry feeds was 38%, 37%, 19% and 17% in layer mash, grower mash, starter mash and finisher mash, respectively, contrary to previous studies that recorded prevalence of 20%, 0%, 40% and 25% in layer mash, grower mash, starter mash and finisher mash, respectively [14] and prevalence of 21%, 38%, 31% and 33% in layer mash, grower mash, starter mash and finisher mash respectively in Tanzania [25]. The disparities of Salmonella prevalence could be due to differences in sampling, testing methods and difficulties in Salmonella detection methods [25].

The prevalence of 58% of Escherichia coli obtained was similar to a related study carried out in Bangladesh that reported prevalence of 57% of Escherichia coli [26]. Other related studies reported different prevalence of 16% in Iraq [1] and in Nigeria 10.6% and 11% [27, 29]. Prevalence of bacteria varies considerably depending on nature of production, country and detection methods applied [30]. Microbial contamination of poultry feeds of plant and animal origin has also been associated with harvesting, manufacturing and climatic conditions encountered [12]. Therefore, it is important to reinforce hygienic handling of feeds and preventive control measures to minimize the danger of potential animal and human health hazards.

The different types of poultry feeds recorded varied bacterial load. The varying results in this study could be attributed to methods of harvesting raw materials, different climatic conditions, food formulation, and storage and transportation technologies [12, 27]. The high bacteria count in layer mash could be due to use of fish wastes as animal proteins which harbors heavier bacterial growth [14]. The differences in bacterial load in different types of poultry feed could also be as a result of mixed infections with other microbes and different management practices [31]. Findings in this study indicates that contaminated poultry feed could be source of infections and thus not fit for animal consumption [32, 33].

The current study recorded different antimicrobial resistance patterns of Salmonella sp. and E. coli. Both isolates of Salmonella and E. coli registered the highest resistance to ampicillin, 41% and 71% respectively, and highest susceptibility to ciprofloxacin, 83% and 100% respectively. The isolates of E. coli indicated highest resistance to ampicillin 71%, followed by tetracycline 10%, co-trimozaxole and ceftriazone 7% and ciprofloxacin 0%. This was similar to a previous study in Bangladesh that recorded ciprofloxacin as the most effective antibiotic against E. coli isolates from poultry feeds [34]. Contrary to previous related study in Bangladesh that reported resistance of 30% to ciprofloxacin, 20% to gentamicin, 60% to nalidixic acid and 0% to ceftriaxone among Salmonella isolates from poultry feeds, the current study recorded the highest resistance to ampicillin 41%, tetracycline and ceftriaxone 5%, co-trimoxazole 2% and ciprofloxacin 0% [35]. In Kenya, a study on antimicrobial resistance in Salmonella and E. coli isolates from poultry wastes reported high resistance to amoxicillin which is a beta-lactam, followed by tetracycline and co-trimoxazole [36]. High resistance to co-trimoxazole, beta-lactams and tetracycline among bacterial isolates from chicken in Kenya was also reported [37, 38]. This suggests possible transmission of antibiotic resistant bacteria through poultry feed to poultry.

The resistant isolates of Salmonella sp. and Escherichia coli carried TEM and SHV genes. Dfr and strB genes were also carried among the resistant isolates of Salmonella sp. and Escherichia coli. Most of studies on poultry feeds have not reported on antimicrobial resistance genes [26, 35, 39]. Nevertheless, a study in India on antimicrobial resistance reported absence of major extended spectrum beta-lactamase in Salmonella isolates from poultry feeds [40].

Therefore, poultry feeds are potential source of antimicrobial resistant genes that can be transferred to poultry and humans and pose a health threat to the society.

Conclusion

This study found out that poultry feeds harbor bacteria and resistance genes. This indicated a threat to public health including humans and animals. It’s important for poultry feeds to be assessed for microbial quality by manufacturers and health authorities to facilitate feed safety.

Limitation

This study never assessed the source of the resistant genes. The acquisition of the resistance genes could be from humans during processing of the feeds or prior contamination of raw materials of the feeds with microorganisms.

Availability of data and materials

The data sets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Abbreviations

SHV :

Sulphydryl variable enzyme

Dfr :

Dihydrofolate reductase

TEM :

Temoneira

strB :

Streptomycin resistant gene

References

  1. Al-Musawi ML, Hussein SB, Gatoof MJ, Hanash NA, Abdulkareem BZ. Bacterial contamination of imported poultry feed in Iraq. Pharm Biol Eval. 2016;3(5):495–9.

    Google Scholar 

  2. Adyanju GT, Ishola O. Salmonella and Escherichia coli contamination of poultry meat from a processing plant and retail markets in Ibadan, Oyo State, Nigeria. Springerplus. 2014;3(1):139.

    Article  Google Scholar 

  3. Maqsood A. Salmonella prevalence in the poultry feed industry in Pakistan. 2012.

  4. Tahir MF, Afzal F, Athar M. Prevalence and antimicrobial susceptibility patterns of Salmonella Enteritidis and Salmonella Typhimurium isolates from commercial poultry in Punjab, Pakistan. Iproceedings. 2018;4(1):e10639.5.

    Google Scholar 

  5. Denli M, Demirel R. Replacement of antibiotics in poultry diets. CAB Rev. 2018;13(035):1–9.

    Article  Google Scholar 

  6. Mehdi Y, Létourneau-Montminy MP, Gaucher ML, Chorfi Y, Suresh G, Rouissi T, Brar SK, Côté C, Ramirez AA, Godbout S. Use of antibiotics in broiler production: global impacts and alternatives. Anim Nutr. 2018;4(2):170–8.

    Article  Google Scholar 

  7. Van Boeckel TP, Brower C, Gilbert M, Grenfell BT, Levin SA, Robinson TP, Teillant A, Laxminarayan R. Global trends in antimicrobial use in food animals. Proc Natl Acad Sci. 2015;112(18):5649–54.

    Article  Google Scholar 

  8. Butaye P, Devriese LA, Haesebrouck F. Antimicrobial growth promoters used in animal feed: effects of less well known antibiotics on gram-positive bacteria. Clin Microbiol Rev. 2003;16(2):175–88.

    Article  CAS  Google Scholar 

  9. Akinbowale OL, Peng H, Barton MD. Antimicrobial resistance in bacteria isolated from aquaculture sources in Australia. J Appl Microbiol. 2006;100(5):1113.

    Article  Google Scholar 

  10. Diaz-Sanchez S, Moscoso S, Solis de los Santos F, Andino A, Hanning I. Antibiotic use in poultry: a driving force for organic poultry production. Food Prot Trends. 2015;35(6):440–7.

    Google Scholar 

  11. World Health Organization. Antimicrobial resistance: global report on surveillance. Geneva: World Health Organization; 2014.

    Google Scholar 

  12. Onyeze RC, Onah GT, Eluke OC. Bacterial contaminants associated with commercial poultry feeds in Enugu Nigeria. Int J Life Sci Biotechnol Pharma Res. 2013;2(3):432–7.

    Google Scholar 

  13. Kenneth IE, Itohan IM, Martha DJ, Gloria OO, Abdulkarim Y. Identification and antibiogram profile of bacteria associated with poultry feeds used in Wukari, Taraba State, North East, Nigeria. Agric Biosyst Eng. 2017;2(6):48–53.

    Google Scholar 

  14. Okoli C, Ndujihe G, Ogbuewu I. Frequency of isolation of Salmonella from commercial poultry feeds and their anti-microbial resistance profiles, Imo State, Nigeria. Online J Health Allied Sci. 2006;5(2):3.

    Google Scholar 

  15. Chowdhury A, Iqbal A, Uddin MG, Uddin M. Study on isolation and identification of Salmonella and Escherichia coli from different poultry feeds of Savar Region of Dhaka, Bangladesh. J Sci Res. 2011;3(2):403–11.

    Article  Google Scholar 

  16. Nkere CK, Ibe NI, Iroegbu CU. Bacteriological quality of foods and water sold by vendors and in restaurants in Nsukka, Enugu State, Nigeria: a comparative study of three microbiological methods. J Health Popul Nutr. 2011;29(6):560.

    PubMed  PubMed Central  Google Scholar 

  17. Hrizo SL, Kaufmann N. Illuminating cell signaling: using Vibrio harveyi in an introductory biology laboratory. Biochem Mol Biol Educ. 2009;37(3):164–9.

    Article  CAS  Google Scholar 

  18. Mohammed HI, Ibrahim AE. Isolation and identification of Salmonella from the environment of traditional poultry farms in Khartoum North. 2012.

  19. Islam MM, Islam MN, Sharifuzzaman FM, Rahman MA, Sharifuzzaman JU, Sarker EH, Shahiduzzaman M, Mostofa M, Sharifuzzaman MM. Isolation and identification of Escherichia coli and Salmonella from poultry litter and feed. Int J Nat Soc Sci. 2014;1(1):1–7.

    Google Scholar 

  20. Kebede A, Kemal J, Alemayehu H, Habte MS. Isolation, identification, and antibiotic susceptibility testing of Salmonella from slaughtered bovines and ovines in Addis Ababa Abattoir Enterprise, Ethiopia: a cross-sectional study. Int J Bacteriol. 2016;2016. https://doi.org/10.1155/2016/3714785.

  21. Clinical Laboratory Standards Institute. Performance standards for antimicrobial susceptibility testing: 16th informational supplement, M100-S24, 2014, Wayne, PA, USA.

  22. Silva GA, Bernardi TL, Schaker PD, Menegotto M, Valente P. Rapid yeast DNA extraction by boiling and freeze-thawing without using chemical reagents and DNA purification. Braz Arch Biol Technol. 2012;55(2):319–27.

    Article  Google Scholar 

  23. Sepp R, Szabo I, Uda H, Sakamoto H. Rapid techniques for DNA extraction from routinely processed archival tissue for use in PCR. J Clin Pathol. 1994;47(4):318–23.

    Article  CAS  Google Scholar 

  24. Lorenz TC. Polymerase chain reaction: basic protocol plus troubleshooting and optimization strategies. J Vis Exp. 2012;22(63):e3998.

    Google Scholar 

  25. Mdemu S, Mathara JM, Makondo ZE. Isolation of Salmonella in commercial chicken feeds in Ilala district. Am Sci Res J Eng Technol Sci (ASRJETS). 2016;19(1):1–8.

    Google Scholar 

  26. Sultana N, Haque MA, Rahman MM, Akter MR, Begum MD, Fakhruzzaman M, Akter Y, Amin MN. Microbiological quality of commercially available poultry feeds sold in Bangladesh. Asian J Med Biol Res. 2017;3(1):52–60.

    Article  Google Scholar 

  27. Matthew O, Chiamaka R, Chidinma O. Microbial analysis of poultry feeds produced in Songhai farms, Rivers State, Nigeria. J Microbiol Exp. 2017;4(2):00110.

    Google Scholar 

  28. Omololu J, Bamidele KF. Antimicrobial susceptibility pattern of S. aureus and Salmonella sp. isolated from poultry feed sold in Ile-Ife, Nigeria. Arch Clin Microbiol. 2017;8(3). https://doi.org/10.4172/1989-8436.100039.

  29. Okogun GR, Jemikalajah DJ, Ebhohimen EV. Bacteriological evaluation of poultry feeds in Ekpoma, Nigeria. Afr J Cell Pathol. 2016;6:6–9.

    Google Scholar 

  30. Agyare C, Boamah VE, Zumbi CN, Osei FB. Antibiotic use in poultry production and its effects on bacterial resistance. In: Antimicrobial resistance—a global threat. Rijeka: IntechOpen; 2018.

    Google Scholar 

  31. Ahmed NT. Bacterial contamination in poultry feed in Khartoum State, Master Theses. Omdurman Islamic University. 2002.

  32. Maciorowski KG, Herrera P, Jones FT, Pillai SD, Ricke SC. Effects on poultry and livestock of feed contamination with bacteria and fungi. Anim Feed Sci Technol. 2007;133(1–2):109–36.

    Article  CAS  Google Scholar 

  33. David OM, Ogunlade JT. Qualities of poultry feeds produced by local small-scale feed mills in Ekiti State, Nigeria: a public health and feed safety study. Res Opin Anim Vet Sci. 2013;3(9):297–302.

    Google Scholar 

  34. Mohanta MK, Islam MS, Saha AK, Khatun S, Khatun Z. Antibiogram profiles of bacterial isolates from poultry feeds and moribund hens in Rajshahi, Bangladesh. Imp J Interdiscip Res. 2016;2(5):41–6.

    Google Scholar 

  35. Roy CR, Ahmed T, Uddin MA. Microbiological analysis of poultry feeds along with the demonstration of the antibiotic susceptibility of the isolates and the antibacterial activity of the feeds. Bangladesh J Microbiol. 2017;34(2):103–7.

    Article  Google Scholar 

  36. Langata LM, Maingi JM, Musonye HA, Kiiru J, Nyamache AK. Antimicrobial resistance genes in Salmonella and Escherichia coli isolates from chicken droppings in Nairobi, Kenya. BMC Res Notes. 2019;12(1):1–6.

    Article  Google Scholar 

  37. Wesonga SM, Muluvi GM, Okemo PO, Kariuki S. Antibiotic resistant Salmonella and Escherichia coli isolated from indiginous Gallus domesticus in Nairobi, Kenya. East Afr Med J. 2010;87(5):205–10.

    CAS  PubMed  Google Scholar 

  38. Mutsami AN. A comparative study of antibiotic resistance profiles among enteric bacteria in broilers and traditional chicken from selected farms in Kericho, Kenya. Doctoral dissertation, Thesis from Kenyatta University, Kenya.

  39. Shilangale RP, Di Giannatale E, Chimwamurombe PM, Kaaya GP. Prevalence and antimicrobial resistance pattern of Salmonella in animal feed produced in Namibia. Vet Ital. 2012;48(2):125–32.

    PubMed  Google Scholar 

  40. Samanta I, Joardar SN, Das PK, Das P, Sar TK, Dutta TK, Bandyopadhyay S, Batabyal S, Isore DP. Virulence repertoire, characterization, and antibiotic resistance pattern analysis of Escherichia coli isolated from backyard layers and their environment in India. Avian Dis. 2014;58(1):39–45.

    Article  Google Scholar 

Download references

Acknowledgements

We would like to appreciate all the owners of the poultry feeds stores that participated in this study. We also wish to appreciate the laboratory technologists from the department of Microbiology, Kenyatta University for their support during the laboratory experiments.

Funding

Not applicable.

Author information

Authors and Affiliations

  1. Department of Microbiology, Kenyatta University, P.O Box 43844-00100, Nairobi, Kenya

    Dorica Gakii Ngai & Anthony Kebira Nyamache

  2. Department of Pant and Microbial Sciences, Kenyatta University, P.O Box 43844-00100, Nairobi, Kenya

    Omwoyo Ombori

Authors
  1. Dorica Gakii Ngai
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Anthony Kebira Nyamache
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Omwoyo Ombori
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

DGN was engaged in designing the study, sample collection, analysis of samples, interpretation of the data and drafting the manuscript. AKN and OO conceptualized the idea, helped in the planning of the experiment, and supervised sample analysis, interpretation of data and review of the article. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Dorica Gakii Ngai.

Ethics declarations

Ethics approval and consent to participate

Ethical clearance was not required. Poultry feeds were bought from the outlets. The study was approved by the Kenya National Commission for Science, Technology and Innovation and authorization given by County Commissioner, Kiambu County Kenya.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Additional file 1: Table S1.

Antimicrobial susceptibility profiles of Escherichia coli.

Additional file 2: Figure S1.

PCR amplification of TEM genes.

Additional file 3: Figure S2.

PCR amplification of SHV genes.

Additional file 4: Figure S3.

PCR amplification of strB genes.

Additional file 5: Figure S4.

PCR amplification of Dfr genes.

Additional file 6: Table S2.

Distribution of resistance genes.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ngai, D.G., Nyamache, A.K. & Ombori, O. Prevalence and antimicrobial resistance profiles of Salmonella species and Escherichia coli isolates from poultry feeds in Ruiru Sub-County, Kenya. BMC Res Notes 14, 41 (2021). https://doi.org/10.1186/s13104-021-05456-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s13104-021-05456-4

Keywords

BMC Research Notes

ISSN: 1756-0500

Contact us