الفهرس 
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Abstract
Campylobacter is considered to be the most common cause of bacterial diarrheal illness and many cases are thought to be acquired from consumption of undercooked poultry or through cross-contamination of other foods during the preparation of poultry. The numbers of cases of human disease in Egypt with Campylobacter have increased but nothing is known about the specific source of infection in Egypt or about the incidence of Campylobacter in Egyptian reared poultry.
This study aimed to:
1) Enumerate Total Bacterial Counts (TBC) and campylobacters in soil and fecal samples collected from chicken farms.
2) Enumerate Total Bacterial Counts (TBC) and campylobacters in different chicken carcasses during processing.
3) Differentiate C. jejuni from C. coli isolates.
4) Enumeration of Total Bacterial Counts (TBC) and campylobacters after chickens cooking.
Therefore we achieved those objectives as follow:
1- We enumerated both campylobacters and total bacterial counts in the soil and fecal samples of four conventional chicken Egyptian flocks in North Sinai governorate.
2- We enumerated both campylobacters and total bacterial counts during process at the slaughterhouse. Samples were taken from chicken carcasses at six different stages during processing.
3- We studied the effect of post-slaughter chilling on the survival of campylobacters at 4°C and −20°C.
4- We studied the effect of cooking (frying, microwaving, boiling, and barbecuing) on the survival of campylobacters and total bacterial counts.
The results indicated that, all four flocks were infected with Campylobacter spp. before processing and these were also detected at the slaughterhouse on the chicken carcasses where C. jejuni was the dominant species. The highest Campylobacter counts, (mean 9.3 CFUg-1), were detected in the intestinal contents of live birds, but high levels of contamination were also found on fresh cooled and frozen chicken meat samples (7.4 CFUg-1 and 7.8 CFUg-1 respectively). This high level and the continuous presence of Campylobacter in the slaughterhouse constitute a risk for transmission to negative carcasses. Our findings indicate that chilling and freezing processes have a limited effect in reducing contamination of final products. As in other parts of the world, chickens in Egypt that enter the slaughterhouse contaminated with Campylobacter represent a risk to consumers’ health in cases of improper handling or cooking practices.
The results indicated that the values of TBC and Campylobacter counts, 10.6 and 8.5 log10 CFUg-1 respectively, were decreased to undetectable limit after cooking except with chicken parts after microwaving and after barbecuing (2.3 and 2.6 log10 CFUg-1 respectively). The structure of chicken skin is such that it could support the survival of Campylobacter for a long time, since it contains many folds and deep crevices projecting inward from the skin surface which can protect Campylobacter within microenvironments. Additionally, the insufficient cooking temperature may be is another reason for not killing the hidden campylobacters in the pores, folds and deep crevices in chicken skin surface.
Good practices during poultry processing such as decontamination of equipment, the use of counterflow multistage water systems during scalding and disinfecting the carcasses might reduce the poultry contamination with campylobacters
In conclusion, the findings indicate that the high rate of cecal carriage with Campylobacter at the time of slaughtering is a key factor in the occurrence of Campylobacter on chicken carcasses. The results also indicate that chilling process has a limited effect in the final products Campylobacter contamination because poultry enter the slaughter processing with high counts of contamination. As a result, high percentage of the chilled and frozen poultry carcasses leaving the slaughterhouses are Campylobacter contaminated and this may represent a health risk to consumers, if proper cooking practices are not employed. Consequently, monitoring Campylobacter contamination at different stages of chicken production would be helpful.