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The recently described atypical porcine pestivirus (APPV) has been associated with congenital tremor (CT) type A-II in piglets in different countries. Another important neurological pathogen of pigs is porcine teschovirus (PTV), which has been associated with non-suppurative encephalomyelitis in pigs with severe or mild neurological disorders. There have been no reports of APPV and/or PTV coinfection associated with CT or encephalomyelitis in Brazilian pig herds. The aim of this study was to describe the pathological and molecular findings associated with simultaneous infection of APPV and PTV in piglets with clinical manifestations of CT that were derived from a herd with high rates of CT-associated lethality. In 2017, three piglets from the same litter with CT died spontaneously. The principal pathological alterations in all piglets were secondary demyelination and hypomyelination at the cerebellum, brainstem and spinal cord confirmed by histopathology and luxol fast blue-cresyl violet stain. Additional significant pathological findings included multifocal neuronal necrosis, neuronophagia and gliosis found in the cerebral cortex and spinal cord of all piglets, while atrophic enteritis and mesocolonic oedema were observed in some of them. APPV and PTV RNA were detected in the central nervous system of affected piglets, and PTV was also detected in the intestine and faeces. The pathological alterations and molecular findings together suggest a dual infection due to APPV and PTV at this farm. Moreover, the combined effects of these pathogens can be attributed to the elevated piglet mortality, as coinfections involving PTV have a synergistic effect on the affected animals.

Porcine group A rotavirus (PoRVA) is a major cause of neonatal diarrhea in suckling and recently weaned piglets worldwide. The involvement of non-group A rotavirus in cases of neonatal diarrhea in piglets are sporadic. In Brazil there are no reports of the porcine rotavirus group C (PoRVC) as etiologic agent of the diarrhea outbreaks in piglets. The aim of this study was to describe the identification of rotavirus group C in single and in mixed infection with rotavirus groups A and B in three neonatal diarrhea outbreaks in suckling (≤21-day-old) piglets, with 70% to 80% and 20% to 25% of morbidity and lethality rates, respectively, in three pig herds located in the state of Santa Catarina, Brazil. The diagnosis of PoRV in the diarrheic fecal samples was performed using polyacrylamide gel electrophoresis (PAGE) to identify the presence of porcine rotavirus groups A, B (PoRVB), and C, and by RT-PCR (PoRVA and PoRVC) and semi-nested (SN)-PCR (PoRVB) to partially amplify the VP4 (VP8*)-VP7, NSP2, and VP6 genes of PoRVA, PoRVB, and PoRVC, respectively. One RT-PCR (PoRVA and PoRVC) and SN-PCR (PoRVB) product of each group of rotavirus of each diarrhea outbreak was submitted to nucleotide (nt) sequence analysis. Based on the PAGE technique, 4 (25%) and 1 (6.25%) of the 16 diarrheic fecal samples evaluated in the first outbreak presented PoRVA and PoRVC electropherotype, respectively, and 11 (68.75%) were negative. In the second outbreak, 3 (42.85%) of the 7 fecal samples evaluated presented PoRVA electropherotype, and in 3 (42.85%) and in 1 (14.3%) fecal samples were detected inconclusive and negative results, respectively. Three (30%) of the 10 fecal samples of the third outbreak presented PoRVC electropherotype; 5 (50%) and 2 (20%) samples showed negative and inconclusive results, respectively. Based on the RT-PCR and SN-PCR assays in the first neonatal diarrhea outbreak, PoRVC was detected in 13 (81.2%) of the 16 diarrheic fecal samples evaluated. PoRVC single infection was identified in 4 (25%) of these samples and mixed infections with PoRVA and PoRVB in 9 (56.2%) fecal samples. All of the seven diarrheic fecal samples evaluated from the second neonatal diarrhea outbreak were positive for PoRVC, whereas its mixed infection with other PoRV groups was detected in 4 (57.2%) samples. In the third outbreak, PoRVC in single infection was detected in all of the 10 diarrheic fecal samples analyzed. In the nt sequence analysis, the PoRVA strains of the first and second outbreaks demonstrated higher nt identity with G4P[6] and G9P [23] genotypes, respectively. The PoRVB strains (first and second outbreaks) and the PoRVC

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The aim of this study was to investigate the genetic diversity of the VP6, VP7, and VP4 genes of 15 Brazilian wild-type porcine RVC strains identified in diarrheic fecal samples. The VP6 gene analysis demonstrated heterogeneity between the 15 RVC strains, which clustered in three distinct genotypes (I1, I5, and I6). In the VP7 and VP4 gene analysis, the genotype combination G6P[4] was detected in only one strain (UEL-77), while G6P[5] was the most commonly (n = 14) detected in RVC strains identified in the Brazilian pig herds evaluated, indicating its probable predominance in this country, mainly in 2014.

Porcine group C rotavirus (RVC) is recognised as an enteric pathogen in piglets worldwide. The VP6 gene of RVC is divided into seven I-genotypes. Genotypes I2 and I3 are found in human and bovine strains, respectively; the porcine strains are divided into the other five genotypes (I1, I4-I7). In this study, molecular analysis of nearly the full length of the VP6 gene was performed in 11 Brazilian wild-type porcine RVC strains identified in diarrhoeic faecal samples, which were collected from eight pig farms located in five Brazilian states from piglets of 1-4 weeks of age. The nucleotide sequences of the VP6 gene showed 82.9-100 % identity between the Brazilian strains, 84.9-93.1 % with the prototype Cowden strain, and 82.4-92.2 % with other porcine RVC strains. In the 11 diarrhoeic faecal samples analysed in this study, three distinct porcine RVC genotypes (I1, I5, and I6) were identified and none were predominant. The results presented in this study revealed a high nucleotide diversity of the VP6 gene in porcine RVC field strains circulating in Brazil, which highlights the importance of further epidemiological and molecular surveys worldwide.

We investigated the porcine lymphotropic herpesvirus (PLHV) DNA presence in multiple organs of pigs. Biological samples (n = 136) included tissue fragments of the central nervous system, heart, kidney, liver, lungs, spleen, urinary bladder, and urine. Sixty-eight (50%) organs were PLHV DNA-positive. None of the urine samples were detected with the virus genome. Although the presence of the PLHV DNA in the urinary bladder and kidney has been detected, it was not possible to show whether urine can be considered an effective route of virus shedding. This study warns to the risk of PLHV zoonotic transmission by xenotransplantation of tissues of porcine origin.

2020) Molecular characterization of Brazilian wild-type strains of bovine respiratory syncytial virus reveals genetic diversity and a putative new subgroup of the virus, Veterinary Quarterly, 40:1, 83-96, ABSTRACT Background: Bovine orthopneumovirus, formerly known as bovine respiratory syncytial virus (BRSV), is frequently associated with bovine respiratory disease (BRD). Aim: To perform the molecular characterization of the G and F proteins of Brazilian wildtype BRSV strains derived from bovine respiratory infections in both beef and dairy cattle. Materials and Methods: Ten BRSV strains derived from a dairy heifer rearing unit (n ¼ 3) in 2011 and steers of three other feedlots (n ¼ 7) in 2014 and 2015 were analyzed. For the BRSV G and F partial gene amplifications, RT-nested-PCR assays were performed with sequencing in both directions with forward and reverse primers used. Results: The G gene-based analysis revealed that two strains were highly similar to the BRSV sequences representative of subgroup III, including the Bayovac vaccine strain. However, the remaining seven Brazilian BRSV strains were diverse when compared with strains representative of the BRSV I to VIII subgroups. The central hydrophobic region of the Brazilian BRSV G gene showed the replacement of conserved cysteines and other residues of importance to antibody reactivity. The deduced F gene amino acid sequences from the Brazilian BRSV strains showed changes that were absent in the representative sequences of the known subgroups. Viral isolation on the nasopharyngeal swab suspensions failed to isolate BRSV. Conclusion: Results suggest that these strains represent a putative new subgroup of BRSV with mutations observed in the immunodominant region of the G protein. However, further studies on these Brazilian BRSV strains should be performed to establish their pathogenic potential. ARTICLE HISTORY