الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 114 |  |  |
| | | from | 114 | | |
Abstract
Mycoplasma gallisepticum (MG), a malicious avian pathogen that commonly causes chronic respiratory disease in chickens, is responsible for hurtful economic losses to poultry industries in Assiut governorate as well as the other Egyptian governorates. Fast detection, proper treatment and effective prevention of the problem is considered a main target.
In the current study, different methods for detection and identification of Mycoplasma gallicepticum (MG) in terms of serology, culture identification and molecular characterization were done on several samples taken from 21 locations in Assiut governorate.
The current work sought to detect the incidence of MG among different commercial broiler farms. About 180 serum and organ samples (lung tissues, air sacs, tracheal, heart and liver tissues) taken from 90 diseased freshly dead and slaughtered broiler chickens were collected for MG isolation. Most of the cases showed marked respiratory manifestations.
Serum samples (90) were tested by serum plate agglutination (SPA) in addition to culture identification. Positive bacteriological samples were subjected for molecular identification using polymerase chain reaction (PCR) to ensure presence of MG. The 16SRrna gene was searched for in the positive and suspected samples collected by PCR and this gene has been found in 9 samples representing percentage 10% of the total tested samples.
A complementary part for this investigation we evaluated the MICs of the most commonly used anti-mycoplasmas drugs in Egypt, (e.g. chlortetracycline,
doxycycline, erythromycin, tylosin, tilmicosin, tiamulin, and lincospectin) for MG isolates recovered in this study. The MICs testing showed that erythromycin and tylosin had the lowest MIC values while chlortetracycline had the highest one.