Occurrence of extended-spectrum beta-lactamase-producing Enterobacteriaceae, microbial loads, and endotoxin levels in du
- PDF / 928,431 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 9 Downloads / 168 Views
RESEARCH ARTICLE
Open Access
Occurrence of extended-spectrum betalactamase-producing Enterobacteriaceae, microbial loads, and endotoxin levels in dust from laying hen houses in Egypt Marwa F. E. Ahmed1,2, Hazem Ramadan2, Diana Seinige3, Corinna Kehrenberg4, Amr Abd El-Wahab5, Nina Volkmann1, Nicole Kemper1 and Jochen Schulz1*
Abstract Background: Poultry houses are often highly contaminated with dust, which might contain considerable amounts of microorganisms and endotoxins. The concentrations of microorganisms and endotoxins in dust from laying hen houses in Egypt are unknown. However, to estimate the risks for birds, the environment, and people working in laying hen houses, it is important to gather information about the composition of these dusts. Here we report the microbial loads, the occurrence of antimicrobial-resistant bacteria, and endotoxin concentrations in dust samples from 28 laying hen farms in Dakahliya Governorate, Egypt, and discuss the results relevant to the literature. Results: Pooled settled dust samples (n = 28) were analyzed for total viable counts of bacteria and fungi (CFU/g), the occurrence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, Salmonella spp., and methicillinresistant Staphylococcus aureus (MRSA), and endotoxin concentrations (ng/g). The means and standard deviations of total viable counts were 7.10 × 108 ± 2.55 × 109 CFU/g for bacteria and 5.37 × 106 ± 7.26 × 106 CFU/g for fungi. Endotoxin levels varied from 2.9 × 104 to 6.27 × 105 ng/g. None of the tested samples contained Salmonella spp. or MRSA. In contrast, by direct plating, Enterobacteriaceae were found frequently (57%; n = 16), and suspected ESBLproducing Enterobacteriaceae occurred in 21% (n = 6) of the sampled barns. Using an enrichment method, the detection of Enterobacteriaceae and suspected ESBL-producing Enterobacteriaceae increased to 20 and 16 positive barns, respectively. Taking results from both methods into account, Enterobacteriaceae and suspected ESBL-producing Enterobacteriaceae were detected in 23 barns Overall, 100 ESBL suspected isolates (Escherichia coli, n = 64; Enterobacter cloacae, n = 20; and Klebsiella pneumoniae n = 16) were identified to species level by MALDI-TOF MS. Isolates from 20 barns (71% positive barns) were confirmed as ESBL producing Enterobacteriaceae by the broth microdilution test. Conclusions: Dust in Egyptian laying hen houses contains high concentrations of microorganisms and endotoxins, which might impair the health of birds and farmers when inhaled. Furthermore, laying hens in Egypt seem to be a reservoir for ESBL-producing Enterobacteriaceae. Thus, farmers are at risk of exposure to ESBL-producing bacteria, and colonized hens might transmit these bacteria into the food chain. Keywords: Laying hens, Settled dust, Bacteria, Fungi, ESBL, Enterobacteriaceae, Endotoxins
* Correspondence: [email protected] 1 Institute for Animal Hygiene, Animal Welfare and Farm Animal Behaviour, University of Veterinary Medicine Hannover, Foundation, Hannover
Data Loading...
