van der Meer, Franciscus JohannesDow, Natalie2013-09-162013-11-122013-09-162013http://hdl.handle.net/11023/983Bovine viral diarrhea virus (BVDV) is an economically significant pathogen of cattle worldwide. The primary propagators of the virus are immunotolerant persistently infected (PI) cattle, which constantly shed large quantities of virus throughout life. The current study has characterized the viral variability in multiple body compartments of PI cattle through analysis of E2 and NS5B sequences. Phylogenetic analysis demonstrated that BVDV exists as a quasispecies distribution within PI cattle. Viral variants were not strictly compartmentalized, although the central nervous system was implicated as an important viral reservoir that may play a role in the emergence of neurovirulent strains. Additionally, vertical transmission of PI resulted in a genetic bottleneck, which is likely followed by generation of diversity by polymerase infidelity and selection processes thereafter. The identification of quasispecies within PI cattle exemplifies the role of this host in viral propagation and highlights the complex dynamics of BVDV pathogenesis, transmission, and evolution.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.VirologyBVDVMolecularEpidemiologymaster thesis10.11575/PRISM/26272