Identification of animal rabies in Inner Mongolia and analysis of the etiologic characteristics

Abstract

Objective: To perform pathological observation and etiological identification of specimens collected from dairy cows, beef cattle and dogs which were suspected of rabies in Inner Mongolia in 2011, and analyze their etiological characteristics.

Methods: Pathological observation was conducted on the brain specimens of three infected animals with Hematoxylin-Eosin staining, followed by confirmation using immunofluorescence and nested RT-PCR methods. Finally, phylogenetic analysis was conducted using the virus N gene sequence amplified from three specimens.

Results: Eosinophilic and cytoplasmic inclusion bodies were seen in neuronal cells of the CNS; and rabies non-characteristic histopathological changes were also detected in the CNS. The three brain specimens were detected positive. N gene nucleotide sequence of these three isolates showed distinct sequence identity, therefore they fell into different groups in the phylogenetic analysis. N gene in the cow and dog had higher homology with that in Hebei isolate, but that in the beef cattle had higher homology with that in Mongolian lupine isolate and Russian red fox isolate.

Conclusion: Rabies were observed in the dairy cow, beef cattle and canine in the farm in Inner Mongolia, in 2011, which led to a different etiologic characteristics of the epidemic situation.

Keywords: Cow; Histopathology; Phylogeny; Rabies.