Bovine pestiviruses, e.g., bovine viral diarrhea virus types 1 (BVDV-1 or Pestivirus A), BVDV-2 (Pestivirus B), and HoBi-like pestiviruses (HoBiPeV or Pestivirus H), have been shown to circulate in Brazilian cattle in varied proportions. In this study, we identified genetically pestiviruses circulating in beef cattle in Rio Grande do Sul, the southern most Brazilian state. Screening of serum of 15.584 beef calves destined to be export by an antigen capture ELISA and, subsequently, by reverse-transcription polymerase chain reaction (RT-PCR), revealed 135 containing pestivirus RNA. Genetic typing of these viruses based on nucleotide sequencing and phylogenetic analysis of the 5′ untranslated region (5′ UTR) of the viral genome allowed for the identification of 90 different viruses, being 38 BVDV-1 (42.2%), 31 BVDV-2 (34.4%), and 21 HoBiPeV (23.4%). Among BVDV-1, only subtypes BVDV-1a (n = 28, 31.1%) and BVDV-1b (n = 10, 11.1%) were identified. All 31 BVDV-2 isolates belonged to BVDV-2b subtype and the 21 HoBiPeV viruses clustered to subgroup 3a. Thus, this study provides an approximate genetic profile of pestiviruses circulating in beef cattle in a traditional Brazilian beef cattle-raising state.

The pestiviruses bovine viral diarrhea virus 1 and 2 (BVDV-1 and -2, respectively) and HoBi-like pestivirus (HoBiPeV) are important pathogens of cattle, and a number of reverse-transcription PCR (RT-PCR)-based assays have been developed for their detection in clinical specimens. We evaluated a newly designed set of pan-bovine pestivirus primers (BP189-389) in a gel-based RT-PCR screening test for pestiviruses in the sera of beef calves destined for export from southern Brazil. Serum samples positive for BVDV antigens by an antigen ELISA (n = 135) were submitted to RT-PCR assays using different sets of primers, followed by nucleotide sequencing of the amplicons. RT-PCR with pestivirus primers 324-326 detected 110 positive samples: BVDV-1 (n = 62), BVDV-2 (n = 38), and HoBiPeV (n = 10). A PCR using primers HCV90-368 detected 97 positive samples (64 BVDV-1; 33 BVDV-2). An additional RT-PCR round using BVDV-2-specific primers (2F-2R) detected 45 positive samples (including 38 detected by primers 324-326 and 33 by HCV90-368); whereas a RT-PCR using HoBiPeV-specific primers (N2-R5) detected 26 positive samples (including 10 detected by primers 324-326).The assay using the primers BP189-389 detected all 135 ELISA-positive samples, including the 26 HoBiPeV detected by primers N2-R5. Our results demonstrated that primers BP189-389 compare favorably against other primer sets in the detection of bovine pestiviruses, especially HoBiPeV. This conventional PCR may be useful for efficient detection of pestiviruses in bovine sera and other specimens as well, especially in laboratories without real-time PCR equipment.

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Sheep are considered less susceptible to leptospirosis than other livestock species, and reports of reproductive problems are scarce in scientific literature. Thus, our objective was to report an epidemic outbreak of leptospirosis in a flock in southern Brazil, causing economic impact represented by several numbers of abortions and barren ewes. From a flock of 602 sheep, 79 ewes had problems during gestational period. Blood samples were collected from 25 of these 79 ewes, 10 with confirmed abortion, 10 barren, and 5 ewes that delivered normally. Serum was separated and subjected to serological evaluation. Samples were examined for Leptospira antibodies by the microscopic agglutination test (MAT) as well as subjected to a differential diagnosis for toxoplasmosis and neosporosis. From the 25 sera analyzed, 19 (76 %) were positive while 6 (24 %) were negative, with single serovar response observed in 12/19 (63.16 %) while mixed serovar positivity was observed in 7/19 (36.84 %). Regarding to serovar prevalence, Hardjo titration was observed in 15/19 (78.95 %) and Wolffi in 9/19 (47.37 %). No samples were positive for toxoplasmosis or neosporosis. Therefore, based on the serological results reached by MAT, it is possible to strongly suggest the participation of Leptospira spp., especially serovars Hardjo and Wolffi, in the reproductive flaws reported in this short communication.