الفهرس 
Chapter I : IntroductionOnly 14 pages are availabe for public view
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Abstract
C. perfringens is anaerobic organism ables to produce spores which are
also able to survive normal cooking temperatures, these spores can grow rapidly
in cooked food, particularly meat which has been cooled slowly and stored in a
worm places.
C. perfringens has an important role as one of food poisoning
microorganism thus the present study was directed to measure its counting,
incidence and heat resisting in fresh meat after slaughter and processed meat.
A total of 165 meat samples were collected from Cairo abattoirs,
butchers and supermarkets, 90 were from fresh meat obtained after slaughtering
(30 cattle meat, camel meat and chicken meat) and 75 processed meat 45
sausages and 30 luncheons.
The total anaerobic count in the examined cattle, camel, chicken meat
samples with a mean value of 2.17 x 103 ± 1.2 x 103 & 8.7 x 103 ± 3.9 x 103 and
1.5 x 103 ± 6.8 x 102 & 5.7 x 103 ±1.2 x 103 organisms /g for fore and hind
quarter, respectively and 3.9 x 104 ± 1.7 x 103 and 6.1 x 103 ±2.7 x 103
organisms /g for breasts and thighs, respectively. In cattle, camel and chicken
the mean value of T.A.C. in sausages samples was 8.7 x 102 ± 2.5 x 102 , 8.9 x
103 ± 6.1 x 103 and 1.8 x 103 ± 1.6 x 103, while in cattle and chicken luncheon
was 6.5 x 103 ± 2.1 x 103 and 1.3 x 104 ± 1.2 x 104 , respectively.
The mean value of C. perfringens count in cattle and camel (fore and hind
quarter ) was 1.7 x 102 ± 3.5 x 10, 2.1 x 103 ± 1.1 x 103, 2.2 x 103 ± 9.03 x 102,
2.4 x 103 ± 6.7 x 102, respectively.
In chicken meat (breasts and thighs) the mean value was 6.6 x 103 ±5.4 x 103
and 2.1 x 103 ± 1.4 x 103, respectively, while the mean value of C. perfringens
count in cattle, camel and chicken sausages was 1.8 x 102 ± 1.5 x 102, 3.9 x 103
± 2.3 x 103 and 3.3 x 102 ± 2.2 x 102, respectively but in both cattle and chicken
luncheon was 1.1 x 103 ± 5.09 x 102 and 9.6 x 102 ± 5.15 x 102, respectively.
Clostridial species other than C. perfringens could be isolated and
identified from the different examined samples such as C. bifermentans, C.
sporogens, and C. subterminal and C. tertium.
The percentage of isolation in cattle, camel, chicken meat were 0%, 3.33 %, 10
% and 66.7 % ; 3.33 %, 6.66 %, 6.66 % and 3.33 %, ; 10 %, 10 %, 16.7 % and
6.66 %, while in cattle, camel, chicken sausages were 6.67 %, 13.33 %, 33.33
%, and 6.67 %, ; 6.67 %, 6.67 %, 6.67 % and 0 % ; 13.33 %, 13.33 %, 26.67 %
and 6.67 %, wlile in cattle and chicken luncheon the percentage were 6.67 %,
20 %, 20 % and 26.67 % ; 26.67 %, 13.33 %, 6.67 % and 6.67 %, respectively.
The isolation rate of C. perfringens in raw cattle and camel meat samples
were 20 % , 33.4 %, 46.7 % and 60 % for fore and hind quarters respectively,
while in raw chicken meat samples were 60 % and 73.33 % for breasts and
thighs, respectively. In cattle, camel and chicken sausages the percentage of
isolation were 20 %, 20 % and 13.4 %. respectively. While in cattle and chicken
luncheon were 46.7 % and 33.4 %, respectively.
The toxigenicity of C. perfringens isolated from examined cattle, camel,
chicken meat and their meat product samples were 64 samples (38.78 %) 41
strains (24.84 %) proved to be toxigenic, while 23 (13.9 %) were not
toxigenic.
Typing of C. perfringens strain showed that C. perfringens type A was
superior to other types isolated from all examined samples. Between 41 strain of
C. perfringens isolated from fresh and processed meat 8 strains were type D, the
rest were type A (33 strain), type B and C failed to be detected in all examined
samples.
The isolated strains were examined for heat resistance , the results showed
that 33 out of 64 isolates of C. perfringens recovered from cattle, camel and
chicken meat and their products were heat resistance (3 strains resist boiling for
one hour, 10 strains resist boiling up to 45 min and all strain resist boiling up to
15 min ).
The C. perfringens type A isolates collected from fresh and processed
meat samples were tested by mouse bioassay to determine their
enterotoxigenicity. The percentages of enterotoxigenic C. perfringens type A
were 33.4 %, 30 % and 63.6 % for cattle, camel and chicken meat & their
products, respectively.