الفهرس | Only 14 pages are availabe for public view |
Abstract Breeds (Elmandra, Gimmizah, Sinai, Dandarawi, Anshase, Fayoumi, Golden Montazah , Matrouh, Beheri, Dokki) ,SPF Lohmann, High line, Bovans and Rhode island tested by PCR for the presence of resistant gene for marek’s disease (CHB6) in Egypt and revealed that positive for 10 out of 14 breeds (Gimmizah, Sinai, Dandarawi, Fayoumi, Golden Montazah , Matrouh, Beheri, Dokki) also in SPF Lohmann and High line while negative for Bovans, Elmandra, Anshase and Roodiland). The purified positive PCR products were subjected to sequence and Phylogenetic analysis. Positive breeds containing CHB6 gene were experimentally infected by 0.5 ml of 103 PFU of MDV via subcutaneous route under the skin on the back of the neck in one day old unvaccinated chicks. Spleen samples were collected at 20th, 25th, 30th, 35th and 40th weeks revealed negative for the presence of challenged MDV by PCR in those mentioned 10 breeds and positive in Bovans breed. Transmission electron microscope (TEM) is used to confirm MDV infection in Bovans group which demonstrated tumors. Histopathological pictures of brain, sciatic nerve, proventriculus, liver, spleen and kidney confirmed the negativity and positivity of the tested breeds for resistance to MDV infection. Indeed, the study reports the existence of ChB6 gene which found high related to the resistance to develop tumors in MDV-challenged 10 native breeds in Egypt. |