الفهرس 
CoverOnly 14 pages are availabe for public view
 |  | from | 65 |  |  |
| | | from | 65 | | |
Abstract
In the current study , 120 samples of meat and milk products of sheep and goat that raised in Matrouh were collected and were investigated to detect the occurrence of Klebsiella pneumoniae and the presence of S.aureus that have toxic effect on gastrointestinal tract among the analysed food samples.
Routine diagnostic and identification procedure for detection of S. aureus isolates includes:
Isolation of colonies on mannitol agar and paired-parker agar for 24-48 hrs at 37 followed by coagulase assay for suspicious colonies and further detection by biochemical tests including (catalase,oxidase ,Methylred test,Oxidation fermentation test ,Indole test ,Mannitol fermentation test,Citrate utilization test) were carried out.
Coagulase positive Staphylococci isolates are usually needed for additional tests .
Voges-Proskauer test was used to differenciate S.aureus from other coagulase positive species(S.hyicus,S.intermedius). Out of 28 suspected isolates ,The result was positive for the 5 isolates.
Confirmation of the results by genetic detection by making PCR for enterotoxins genes proved its positivity to enterotoxin B gene for one from the 5 suspected isolates.As antibiotics are still used extensively to control bacterial infections necessitated monitoring of the status of bacterial resistance. Antibiotic sensitivity test and methicillin resistance test were perfomed, the increase in resistance to the commonly used antibiotics.
Detection and identification of Klebsiella spp. is done as the following:
Isolation of the separate suspected colony ,which must be characterized by the high viscosity ,on MacConkey agar and incubated at 37 for 24hrs then biochemical tests are done after preparing bacterial film and staining with indian ink stain and detection under light microscope using oil immersion lens,bacteria seemed as dark bacilli surrounded by white capsule.
Biochemical tests include (catalase test, oxidase test ,M-R ,V-P ,Indole, citrate utilization, Hypermucoviscosity) test. The results of these tests increased the susceptibility of being the isolates Klebsiella pneumoniae which was confirmed molecular method.
In Antibiotic sensitivity test that was performed for the 5 isolates, it was found that 4 isolates(isolate 1,3,4,6) were resistant to 3 classes of antibiotics( betalatams,cephalosporins,macrolids) and 2 isolates(isolate 2,5) resist 6 classes of antibiotics,including(betalatams,cephalosporins,macrolids,tetracyclines,sulphona-mides, Amphenicols, carbapenemes).Interestingly,ESBL test showed that the 6 isolates(isolate 1,3,4,6,7,8), that were resistant to 3 classes of antibiotics,were negative ESBL producers and the 2 isolates(isolate 2,5), that resist 6 classes of antibiotics, were positive ESBL producers(pandrug resistant) .
PCR for genetic detection of aerobactin and fimbrya H virulence genes was performed for the isolates 2,5 ,the result showed positive result for presence of the 2 virulence genes in the 2 isolates.
In conclusion, the amazing antibiotic resistance of strains of the Gram +ve S. aureus and the Gram -ve K. pneumoniae contaminated milk, In this isolated geographical area, get us afraid one day the antibiotics will not be enough for treatments of bacterial infections.