Bovine viral diarrhea virus type 1 current taxonomy according to palindromic nucleotide substitutions method

Congenital Cataracts and Microphakia with Retinal Dysplasia and Optic Nerve Hypoplasia in a Calf

Case Description. A two-month-old, female, Aberdeen-Angus calf was presented for congenital cataracts and blindness in both eyes (OU). The dam had a reported history of visual defects (not specified) and had produced other affected calves (per owner history). Ophthalmic examination revealed mature bilateral cataracts, attenuation of the iridic granules, persistent pupillary membranes, and dyscoric pupils. Additionally, the calf had a poor body condition, prognathism, dome-shaped head, excessive nasal drainage, limb contracture, and fever. Histopathology of both eyes revealed lenticular degeneration (congenital cataracts), retinal dysplasia, and optic nerve hypoplasia. BVDV IHC detected antigen within only the left eye (OS), consisting of intrahistiocytic and endothelial immunoreactivity within the ciliary body, iris, and choroid. No BVDV immunoreactivity could be detected in the right eye (OD). This case highlights the unique ocular changes present in in utero BVDV infection of cattle with a different immunohistochemical staining profile than previously described.

Genomic characteristics of classical swine fever virus strains of bovine origin according to primary and secondary sequence-structure analysis

Background:

Classical swine fever virus (CSFV), species member of the family Flaviviridae, is generally considered restricted to domestic and wild suids. The circulation of CFSV has been detected in cattle herds in China and India. Natural infection appeared associated with clinical signs in some cases.

Aim:

The secondary structures of the internal ribosome entry site in the 5′ untranslated region (UTR) were used for the genomic characterization of bovine strains.

Methods:

Sequences have been compared to the representative CSFV strains isolated from pigs, vaccines, and contaminants from porcine cell lines and an ovine strain isolated in Spain.

Results:

The observed sequences from cattle showed a genetic relatedness with live-attenuated vaccine strains used in pigs. Sequence characteristics of the Chinese strain S171 are genetically distant from the previously reported CSFV genotypes, suggesting a new outgroup in the species, described for the first time, and named CSFV-d. Other Chinese strains were genetically closely related to CSFV genotype a2 (Alfort type) pig strains. Indian strains, reported from the states of Tamil Nadu and Meghalaya, were genetically closely related to CSFV genotype a1 (Brescia type) and a5 pig strains, respectively.

Conclusion:

These preliminary observations are new and relevant in countries, where CSFV control and eradication strategies are applied.

Characterization of internal ribosome entry sites according to secondary structure analysis to classify border disease virus strains

Applying palindromic nucleotide substitutions (PNS) method, variable loci of the internal ribosome entry site (IRES) secondary structure in the 5' untranslated region (UTR) of Border disease virus sequences were analysed allowing their allocation into ten IRES classes within the species. Sequence characteristics of Turkish and Chinese strains were highly divergent from other genogroups, indicating geographic segregation and micro-evolutive steps within the species. Observed heterogeneity in the BDV species has to be considered for potential implications on diagnostic tests, control and preventive measures.

Pathogen spread and globalization: The case of Pestivirus heterogeneity in southern Italy

Pestiviruses are responsible for widespread diseases affecting cattle, pigs and other ruminants, presenting a wide range of clinical manifestations, with significant impact on animal production. Given the recent various reports of a relatively high number of new strains and atypical genomic variants, in the present study, ninety-seven genomic sequences from southern Italy have been evaluated applying the palindromic nucleotide substitutions method, based on 5'-UTR secondary structure alignment and computing genetic distance among strains in the internal ribosome entry site. Sequence analysis revealed a highly heterogeneous virus population, indicating the introduction of virus variants of Bovine viral diarrhea virus and Border disease virus species from foreign countries. The application of different analytical procedures was useful to avoid interpretation difficulties. Circulation of heterogeneous virus populations showed the need for more accurate epidemiological investigations and stringent veterinary controls to protect animal health and welfare.