الفهرس 
Part 1 : Introduction
Morphological characters of Clostridia speciesOnly 14 pages are availabe for public view
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Abstract
C. perfringens was recovered from 98 sample (93.3%) out of 105 different minced meat samples regarding to traditional methods and confirmed by real time PCR. In our study C. perfringens isolates revealed double zone of haemolysis on sheep blood agar and black zone on TSC agar (Tryptose sulphite cyclosyrine agar). Total count of viable C. perfringens in the examined minced meat (98)were less than 10 CFU/g in 75 samples and more than 20 colonies in the remaining (23) samples.
These 23 samples showed total countof 2.0 ×102 to 4.5 ×102 with a mean value 3.7×102± 1.07 ×102CFU/g.In our study the lecithinase activity represented the action of C. perfringens alpha toxin on Lecithin of egg yolk which appeared as pearly opalescence zone surrounded the colonies was detected in 33 (33.7%) strains of C. perfringens in the examined minced meat.Moreover, toxin typing of lecithinase positive C. perfringens based on dermonecrotic reactions in albino guinea pig displayed that 33 (33.7%) strains were determined as C. perfringenstype A, while other strains were regarded as non-toxigenic strains (65, 66.3%).In the present study, C. perfringens isolates derived from minced meat isolates were tested against 15 antimicrobial agents .
The C. perfringens isolates were highly sensitive to penicillin (88, 89.8%), followed by erythromycin, tetracycline (65, 66.3%, each), then doxycycline and amoxicillin (64, 65.3 % each). In contrast, C. perfringens isolates were resistance to ofloxacin (96,97.95%), streptomycin, cloxacillin (94, 95.9% each amikacin (90, 91.8%), trimethoprime sulphamethazole (85, 86.7%), oxytetracycline (83,84.7%), cephalothin, cefeprime (80, 81.6% each) and kanamycin(78,79.6%). The Real Time-PCR showed that all 33 tested C. perfringens type A (100%) harbored alpha toxin gene (cpa) and enterotoxin gene (cpe) on the other hand they were negative to beta,epsilon and iota toxin genes.