الفهرس 
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Abstract
In this study, a total of ( 250 ) samples were collected from different ready to eat poultry meat products, 50 samples from each of (Chicken Pane, Chicken Shawarma, Chicken Fajita, Chicken Shish kebab, Chicken Zinger) from vending sites and restaurants of different localities of different level of hygienic measures in Cairo Governorate. These areas were selected because there are high auspices of street vended foods in a period from September 2019 till February 2020.The samples were prepared to detect and identify the specific Campylobacter species bacteriologically by direct plating and selective enrichment methods and molecularly by PCR technique.
As regards to the Bacteriological examination of 250 collected ready to eat poultry products meal, the obtained results revealed the isolation of Campylobacter spp. from only (8) samples out of 250 examined samples with a prevalence rate reached (3.2%) by studding the morphological identification on the selective culture media and microscopically identification as well as the biochemical reactions. The high detection rate of Campylobacter was observed in isolates from chicken Fajita, while the low detection rate of Campylobacter was observed in isolates from Chicken Pane, Chicken Shish kebab, Chicken Zinger.
On the other hand, the all isolated strains proved to be positive for C. jejuni by molecular identification (PCR assay) using specific primers.
For experimental challenge the isolated strains of Campylobacter jejuni which isolated from different sources from street vended poultry meat meal were cultured according to the method of Davis and Di Rita to provide bacteria to investigated the role of cross - contamination in disseminating Campylobacter from raw poultry within a food service operation specializing in poultry dishes. Accordingly, kitchen surfaces within a restaurant in Cairo were sampled between (April and May 2020).
In experimental study, Samples were collected weekly from environmental surfaces and various kitchen surfaces used at different stages of the preparation process from a retail poultry food service operation in Cairo Governorate during unannounced visits at different times of the day.
Confirmatory tests, including Gram’s stains, and biochemical tests (catalase, oxidase, and hippurate hydrolysis), were performed according to standard procedures, as described by Sanders.
Regarding to the experimental examination, the obtained results revealed that with use of an inoculum of 107 cells, viable C. jejuni could not be recovered from the stainless steel surface after 1 hrs. of drying. Also, Campylobacter spp. were not detected in any of the 125 restaurant samples collected.
Tests of the sampling method indicated that as few as 100 Campylobacter cells could be detected if sampling was done within 45 min of inoculation; however, Campylobacter spp. were not detected in 125 swabs of surfaces within the kitchens before heat treated of this food service operation, despite the reported high prevalence of Campylobacter spp. in ready to eat poultry meal, this organism was not detected on surfaces within a kitchen of a restaurant specializing in poultry dishes.
This inability to detect Campylobacter s may be related to routine cleaning of preparation surfaces, adequate preparation and storage of foodstuffs, good worker hygiene, and physical separation of raw foods from cooked foods, limiting cross-contamination. It is also likely that the lack of Campylobacters in samples from this high-volume retail food service operation may also be attributed to the sensitivity of Campylobacter spp. to drying conditions.
from present study, concluded that there is no evidence to suggest that the specific food products tested and premises sampled were acting as a source of Campylobacter for consumers, which the results proved that ready-to-eat foods supplied by retailers and a food service operations are associated with a very low rate of Campylobacter contamination. But, other sources of this organism are likely to be more important in the occurrence of enteric infection caused by Campylobacter spp.
The low prevalence rate of Campylobacter spp. were either not present in the majority of the foods tested, or were present below the detection limit of the method used, or were in a form that could not be detected (e.g., viable but non culturable). So, the use of a DNA-based molecular detection method, such as PCR, may provide some insight into whether the method used here was sensitive enough to detect small numbers of Campylobacter, and may enhance the prospects of recovery of Campylobacter spp. from the environment.
Alternatively, differences in Campylobacter contamination levels in street vended poultry meat meal or in sampling and detection methods may also contribute to the differences in isolation rate observed in this study. This may be partially responsible for the wide variation in isolation rates (0 to 100%) described worldwide