Pathological and Molecular Investigations on Foot and Mouth Virus Outbreaks Among Cattle Herds in Dakahlia Governorate, Egypt

The present study represents an extensive field survey of the pathological affections caused by local Food and Mouth Disease (FMD) virus throughout Dakahlia governorate, North Egypt. The study included 670 cattle belonging to local and Frisian breeds. The age of the examined animals ranged from ten days to four years and they were of both sexes. The morbidity rates among the investigated cattle herds of either Frisian or native origin were 100% and 5% respectively. We observed early mortality in infected calves aging ten days old and older calves. This was concurrently associated with lesions of severe myocarditis which appeared to be responsible for the death. On the other hand, adult cattle showed vesicular lesions, erosions and ulcers on the mucous membrane of the mouth and skin on the feet and udder. In addition, fever, anorexia, and pstyalism were observed. Histopathological examination of both young calves and adult cattle revealed multitude of inflammatory and necrotic lesions in the myocardium, liver, lung, intestine and udder. Molecular examination and gene sequencing revealed the presence of RNA belonging to FMD virus ‘type A' in the affected tissues. The nucleotide sequence of the isolated virus strain was submitted to the gene bank (accession number: BankIt1911105FMD/A/EGY/Dakahlia/ KX083565). In conclusion, the study emphasized the importance of FMD as a viral disease induced relatively high mortality and morbidity especially in young calves and gives an account on the associated pathological lesions.