Related Experiment Video
Updated: May 12, 2026
Detection and Isolation of Campylobacter spp. from Raw Meat
Published on: February 23, 2024
Air samplings in a Campylobacter jejuni positive laying hen flock
Marwa Fawzy El Metwaly Ahmed1, Jochen Schulz, Joerg Hartung
1Institute for Animal Hygiene, Animal Welfare and Farm Animal Behaviour, University of Veterinary Medicine Hannover, Foundation, Germany. mrw_fwzy@yahoo.com
Abstract:
The air in laying hen houses contains high concentrations of airborne bacteria. The numbers of these bacteria can be influenced by the efficiency of the chosen sampling method. In the presented study, AGI-30 Impingers and the Coriolis(®)µ air Sampler were compared in terms of their efficiency in sampling aerobic mesophilic bacteria in a laying hen house. Measurements were conducted in a laying hen flock with high prevalences of C. jejuni in order to investigate if culturable cells of this organism can also be detected by the applied methods. Airborne dust was also analyzed for the presence of C. jejuni specific DNA to assess the possible occurrence of non-culturable C. jejuni in the hen house air. The numbers of mesophilic airborne bacteria ranged from 8 × 10(4) - 2 × 10(6) CFU/m(-3) when sampled using AGI-30 Impingers, and from 2 × 10(5) - 4 × 10(6) CFU/m -3 when sampled using a Coriolis(®)µ air Sampler. The concentrations detected simultaneously by both devices correlated well (rPearson = 0.755), but the Coriolis(®)µ air Sampler showed a significantly higher sampling efficiency (p<0.001). Although, the within flock prevalence of C. jejuni was high during the experiments (between 70-93%), neither of the air sampling methods could detect culturable C. jejuni from the air. However, C. jejuni specific DNA was detected in 15 out of 18 airborne dust samples by mapA PCR. Based on the results, it can be concluded that airborne culturable C. jejuni were not detectable, even with an efficient air sampler, because of their low concentration. Therefore, the risk of airborne infection to poultry workers on inhaling airborne C. jejuni seems negligible. Also, the transmission of culturable C. jejuni to neighboring farms by the airborne route is unlikely. Otherwise, the detection of airborne C. jejuni specific DNA suggests that non-culturable cells could appear in the hen house air, and in future it should be verified whether sampling stress of the air sampling methods could induce the non-culturable state.
Insights
Comparing air sampling methods in laying hen houses revealed the Coriolis®µ sampler is more efficient for bacteria. Culturable Campylobacter jejuni was not detected in the air, suggesting negligible risk to workers and farms.
Area of Science:
- Environmental microbiology
- Poultry health
- Air quality monitoring
Background:
- Laying hen houses harbor high levels of airborne bacteria.
- Effective air sampling methods are crucial for accurate bacterial quantification.
- Campylobacter jejuni (C. jejuni) prevalence in flocks necessitates evaluating airborne transmission risks.
Purpose of the Study:
- To compare the efficiency of AGI-30 Impingers and Coriolis®µ air Sampler for sampling aerobic mesophilic bacteria.
- To investigate the detectability of culturable C. jejuni in laying hen house air.
- To assess the presence of C. jejuni DNA in airborne dust, indicating potential non-culturable forms.
Main Methods:
- Simultaneous air sampling using AGI-30 Impingers and Coriolis®µ air Sampler in a laying hen house.
- Quantification of aerobic mesophilic bacteria (CFU/m³).
- mapA PCR analysis of airborne dust for C. jejuni specific DNA.
Main Results:
- Coriolis®µ air Sampler demonstrated significantly higher sampling efficiency for airborne bacteria (p<0.001).
- Bacterial concentrations correlated well between samplers (rPearson = 0.755).
- Culturable C. jejuni was not detected by either method, despite high flock prevalence (70-93%).
- C. jejuni specific DNA was detected in 15 out of 18 airborne dust samples.
Conclusions:
- The Coriolis®µ air Sampler is more efficient for airborne bacteria in laying hen houses.
- Airborne culturable C. jejuni concentrations are too low for detection, posing negligible inhalation risk to poultry workers.
- Airborne transmission of culturable C. jejuni to neighboring farms is unlikely.
- Detection of C. jejuni DNA suggests the presence of non-culturable cells, warranting further investigation into sampling-induced stress.
