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This report investigated the possible participation of canine distemper virus (CDV) in an eight-year-old, male, Akita dog with neuromuscular disease. Clinically, there was tetraparesis, muscular atrophy, generalized weakness, intolerance to exercise, and diminished or absent spinal reflexes. The dog was serologically negative for Toxoplasma gondii. Necropsy confirmed generalized muscular atrophy. Histopathology revealed white matter demyelinating encephalitis, generalized atrophy and fibrosis of skeletal muscle fibers, myocardial atrophy and fibrosis, loss and demyelination of peripheral nerve fibers, axonal degeneration, endoneural fibrosis, and interstitial pneumonia. Immunohistochemistry identified CDV antigens within the cerebellum, spinal cord, skeletal muscle, lungs, and spleen. RT-PCR and direct sequencing amplified the CDV nucleoprotein gene from the cerebellum and sciatic nerves. Collectively, these findings suggest that this dog demonstrated systemic canine distemper that also affected the muscular system and probably triggered the manifestations of the neuromuscular disease observed in this case. [ABSTRACT FROM AUTHOR]

Sheep Associated-Malignant Catarrhal Fever (SA-MCF) is severe, frequently lethal, lymphoproliferative disease predominantly of ruminants, that is caused by ovine gammaherpesvirus-2 (OvHV-2), a member of the MCF virus (MCFV) complex. However, SA-MCF in sheep is a rare entity with few demonstrations of natural diseases worldwide. This report documents the clinical, radiographical, pathological, immunohistochemical, and molecular findings of SA-MCF in a sheep. A 4-year-old, female, mixed-breed sheep with progressive emaciation for at least one month was humanely euthanized due to poor prognosis. Clinically, the animal had tachypnea, ruminal hypomotility, productive coughing with bilateral muffling sounds during pulmonary auscultation. Radiographical evaluation revealed alveolar opacity of the cranioventral pulmonary region. Grossly, there were distinct rib impressions on the pleural surface of the lungs, suggestive of interstitial pneumonia. Histopathologic evaluation of the lungs revealed several disease patterns including 1) chronic interstitial pneumonia with vasculitis and proliferating vascular lesions, and thrombosis; 2) pulmonary abscesses associated with embolic dissemination of Corynebacterium pseudotuberculosis from superficial lymph node due to caseous lymphadenitis, CLA; 3) granulomatous pneumonia associated with pulmonary nematodes; and 4) chronic pleuritis, probably due to caseous lymphadenitis. Additional significant histologic findings included widespread lymphocytic vasculitis and proliferating vascular lesions in multiple tissues, atrophic enteritis, segmental degeneration of myocardial fibers with lymphocytic pericarditis, lymphocytic interstitial nephritis, and non-suppurative encephalitis. An immunohistochemistry (IHC) assay, based on the monoclonal antibody 15A (MAb-15A), that is specific to all MCFV known to cause MCF, revealed positive, intracytoplasmic, intralesional immunoreactivity, predominantly within bronchial and bronchiolar epithelial cells of the lungs and cryptal epithelial cells of the small intestine, followed by the renal tubular epithelium, cardiomyocytes, and with patchy immunolabelling within neurons of the cerebral cortex. Molecular testing done to detect a wide range of bacterial and viral agents of ruminant diseases, only amplified OvHV-2 DNA from fresh tissue fragments of the lungs, kidney, liver, spleen, and cerebrum. Direct sequencing confirmed that the PCR amplicon derived from the pulmonary fragments had 99.2–99.7% nucleotide sequence identity with OvHV-2 reference strains and strains of OvHV-2 from Brazil. The clinical, radiographical, gross, histopathologic, IHC, and molecular findings in the lungs are consistent with chronic interstitial pneumonia associated with infection by OvHV-2. Furthermore, the non-detection of other viral agents associated with pulmonary diseases in ruminants suggest that OvHV-2 was directly associated with the development of chronic pneumonia in this sheep. Additionally, the dental alterations, CLA, and the pulmonary nematode may have contributed towards the reduced immunological statue of the animal and facilitated the occurrence of SA-MCF. These findings may indicate that OvHV-2 may be a major participant in the pathogenesis of pulmonary disease of sheep under special conditions. Moreover, the proliferating vascular lesions identified in multiple tissues are additional evidence of chronic manifestations of OvHV-2 infections as described in chronic SA-MCF of cattle, while the widespread vasculitis is consistent with SA-MCF. Additionally, the IHC findings using the MAb-15A confirmed that this diagnostic approach is efficient to identify intralesional antigens of OvHV-2. • This report documents the unique manifestation of chronic SA-MCF in a sheep. • OvHV-2 associated with widespread vasculitis and proliferating vascular lesions are described. • OvHV-2 can cause pulmonary disease in the reservoir host of SA-MCF under specific conditions. • Immunohistochemistry using the monoclonal antibody 15A is an efficient in situ diagnostic method for SA-MCF. [ABSTRACT FROM AUTHOR]

Seneca Valley virus (SVV) is the causative agent of an emerging infectious vesicular disease in swine that is clinically indistinguishable from other vesicular diseases of swine. This study utilized healthy suckling piglets (control) and SVV-naturally infected suckling piglets to determine the effects of SVV on lymphoid tissues and determined the SVV RNA load by quantitative RT-PCR (qRT-PCR). Furthermore, immunohistochemistry (IHC) analyses were performed to quantify the expression of T and B cell lymphocytes, natural killer cells, cleaved caspase 3, and ki-67. The main histopathologic finding in the infected group was severe lymphoid depletion. The highest average of SVV RNA load by qRT-PCR (Log10 genomic copies/g of tissue) occurred at the spleen (8.54 ± 0.8), followed by the tonsils (8.04 ± 1.42), and mesenteric lymph nodes (6.90 ± 1.42). The IHC analyses revealed that there was an increased in cellular apoptosis with concomitant reduction in the proliferation of B cells. The results from this study have demonstrated that SVV-infected piglets exhibited decreased lymphocyte density probably due to lymphoid apoptosis, affecting particularly B-cells lymphocytes. • Seneca Valley virus (SVV) induces lymphocytic density reduction and immunodepression in piglets • SVV replicates efficiently in piglet tonsils, mesenteric lymph nodes and spleen. • SVV induces selective apoptosis of B lymphocytes of suckling piglets [ABSTRACT FROM AUTHOR]

• BALF is a good biological sample for the molecular diagnosis of BRD in dairy calves. • Mixed infections of viruses and bacteria were frequent in dairy calves with respiratory disease. • BVDV 1d in BALF samples of dairy heifer calves in a BRD outbreak was characterized. • The calf rearing unit without prophylactic measures for respiratory infections represent a risk factor for BRD. The etiological agents involved in a bovine respiratory disease (BRD) outbreak were investigated in a dairy heifer calf rearing unit from southern Brazil. A battery of PCR assays was performed to detect the most common viruses and bacteria associated with BRD, such as bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV), bovine alphaherpesvirus 1 (BoHV-1), bovine coronavirus (BCoV), bovine parainfluenza virus 3 (BPIV-3), Mannheimia haemolytica , Pasteurella multocida , Histophilus somni , and Mycoplasma bovis. Bronchoalveolar lavage fluid (BALF) samples were taken from 21 heifer calves (symptomatic n = 15; asymptomatic n = 6) that, during the occurrence of the BDR outbreak, were aged between 6 and 90 days. At least one microorganism was detected in 85.7 % (18/21) of the BALF samples. Mixed infections were more frequent (72.2 %) than single infections (27.7 %). The interactions between viruses and bacteria were the most common in coinfections (55.5 %). The frequencies of BRD agents were 38.1 % for BRSV, 28.6 % for BVDV, 33.3 % for BCoV, 42.85 % for P. multocida, 33.3 % for M. bovis , and 19 % for H. somni. BoHV-1, BPIV-3, and M. haemolytica were not identified in any of the 21 BALF samples. Considering that BALF and not nasal swabs were analyzed, these results demonstrate the etiological multiplicity that may be involved in BRD outbreaks in dairy calves. [ABSTRACT FROM AUTHOR]

Bovine respiratory disease (BRD) is a significant global health issue in cattle farming, leading to substantial economic losses. This study analyzed the microbiological profiles of BRD outbreaks in nine dairy cattle herds in southern Brazil. We examined 36 biological samples, including 24 deep nasopharyngeal swabs (NS) and 12 lung tissue, from 29 suckling and 7 weaned heifer calves with acute BRD. PCR and RT-PCR techniques were used to partially amplify the genes of five viruses and four respiratory bacteria. A total of 8 different microorganisms, 4 viruses (bovine viral diarrhea virus, n = 5; bovine coronavirus, n = 3; bovine alphaherpesvirus 1, n = 3; and bovine parainfluenza virus 3, n = 2), and 4 bacteria ( Pasteurella multocida , n = 16; Mycoplasma bovis , n = 8; Histophilus somni , n = 7; and Mannheimia haemolytica , n = 4) were identified in 29 (80.5%) samples. Seven samples (four lung tissue and three NS) were negative for all the microorganisms. Mixed infections were more common (62.1%) than single infections (37.9%). Bacterial nucleic acids were more commonly co-detected in NS than in lung tissue. Nucleic acids from a single pathogen were more frequently detected in lung tissues than in NS. M. bovis was the only bacterium detected in the lower respiratory tract. Understanding the microbiological profiles of the respiratory tracts of dairy calves with clinical signs of BRD is crucial for implementing effective biosecurity measures to prevent BRD in suckling and weaned dairy heifer calves.

Although there are several studies that described the possible participation of Mycoplasmopsis bovirhinis (formerly, Mycoplasma bovirhinis) in respiratory disease in calves worldwide, none of these evaluated the effects of concomitant infections on the shedding of this organism. Accordingly, this study evaluated the effects of simultaneous respiratory infections in dairy calves on the nasal shedding of M. bovirhinis. A statistical two-step model, using univariable and multivariable with logistic regression was developed to investigate and predict the possible effects of simultaneous infections by Histophilus somni, Mannheimia haemolytica, Pasteurella multocida, bovine coronavirus (BCoV), and ovine gammaherpesvirus 2 (OvGHV2) in dairy calves on the nasal shedding of M. bovirhinis. The multivariable analysis demonstrated that dairy calves infected with OvGHV2 have 2.59 times likelihood of nasal shedding of M. bovirhinis relative to calves not infected by OvGHV2, while the odds of nasal shedding of M. bovirhinis was 3.46 times higher in dairy calves infected by M. haemolytica. In contrast, simultaneous respiratory infections in dairy calves by H. somni, P. multocida, and BCoV had no direct effect on the nasal shedding of M. bovirhinis. Consequently, infections by OvGHV2 and M. haemolytica may be possible risk factors for the nasal shedding of M. bovirhinis in dairy calves. These results demonstrated the importance of disease modeling in veterinary medicine to predict and understand the complex outcomes of associations in animals concomitantly infected by several disease pathogens., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Bovine respiratory disease (BRD) is a common global health problem in dairy cattle. The definitive diagnosis of BRD is complex because its etiology involves several predisposing and determining factors. This report describes the etiology of a BRD outbreak in a dairy herd in the mesoregion of Central Eastern Paraná, which simultaneously affected young (calves and heifers) and adult (cows) Holstein-Friesian cattle. Nine biological samples, consisting of five lung samples from two cows and three suckling calves, and four nasal swab samples from heifers, were used for etiological diagnosis. The nucleic acids extracted from lung fragments and nasal swabs were subjected to PCR and RT-PCR assays for partial amplification of the genes of five viruses [bovine viral diarrhea virus (BVDV), bovine alphaherpesvirus 1 (BoAHV1), bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus 3 (BPIV-3), and bovine coronavirus (BCoV)] and four bacteria (Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni) involved in the etiology of BRD. All nine biological samples from the animals with BRD tested negative for BoAHV1, BRSV, BPIV-3, BCoV, and H. somni. Therefore, the involvement of these microorganisms in the etiology of BRD outbreak can be ruled out. It was possible to identify the presence of BVDV and M. bovis in singular and mixed infections of the lower respiratory tract in cattle. BVDV was also identified in two nasal swabs: one as a single etiological agent and the other in association with two bacteria (P. multocida and M. haemolytica). The phylogenetic analysis conducted in the nucleotide sequence of the 5'UTR region and N pro gene of the BVDV amplicons demonstrated that the BVDV field strains of this BRD outbreak belong to subgenotype 2b. To the best of our knowledge, this is the first report of BVDV-2b involvement in the etiology of BRD in Brazil. Finally, it is necessary to highlight that the cattle were obtained from an open dairy herd with biannual vaccinations for BVDV-1a and - 2a., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Ovine gammaherpesvirus 2 (OvGHV2) is a member of Macavirus genus, subfamily Gammaherpesvirinae, family Herpesviridae, and causes sheep associated-malignant catarrhal fever (SA-MCF) in a wide range of ungulates. However, no descriptions of SA-MCF and/or infections due to OvGHV2 were identified in the wild boar (Sus scrofa). This study investigated the occurrence of OvGHV2 in the lungs (n = 44) of asymptomatic, free ranging wild boars captured in several regions of Paraná State, Southern Brazil. A PCR assay targeting the OvGHV2 tegument protein gene amplified OvGHV2 DNA in 4.55% (2/44) of the pulmonary tissues evaluated. Sequence analysis confirmed that the OvGHV2 strains herein identified have 98.4% deduced amino acid (aa) sequence identity with the prototype strain of OvGHV2 and 96.4-100% aa identity with similar strains of OvGHV2 detected in several animal species from diverse countries. These findings confirmed that these two wild boars were infected by OvGHV2, represent the first description of this infection in these animals, and add to the number of pathogens identified in this animal species. Furthermore, these findings contrast earlier descriptions of OvGHV2 in swine since in all previous reports the infected pigs demonstrated clinical manifestations of disease. Consequently, these wild boars from Southern Brazil were subclinically infected or suffered asymptomatic infections by OvGHV2., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Porcine rotavirus (RV) is a major viral agent associated with severe diarrhea in newborn piglets. RVA, RVB, RVC, and RVH are RV species that have already been identified in pigs. RVA is considered the most prevalent and relevant virus in pig production worldwide. This study aimed to evaluate the frequency of RV infection associated with diarrhea in suckling piglets from regular RVA-vaccinated Brazilian pig herds between 2015 and 2021. Therefore, 511 diarrheic fecal samples were collected from suckling piglets aged up to 3 weeks from 112 pig farms located in three main Brazilian pork production regions. All piglets were born to RVA-vaccinated sows. The nucleic acids of RVA, RVC, and RVH were investigated by RT-PCR assays and RVB by semi-nested RT-PCR assay. Of the diarrheic fecal samples analyzed, 221/511 (43.3%) were positive for at least one of the RV species. Regarding the distribution of RV species among the positive fecal samples that presented with only one RV species, 99 (44.8%), 63 (28.5%), and 45 (20.4%) were identified as RVB, RVC, and RVA, respectively. RVH was not identified in diarrheic piglets with a single infection. More than one RV species was identified in 14/221 (6.3%) of the diarrheic fecal samples evaluated. Co-detection of RVB + RVH (11/221; 5.0%), RVA + RVB (1/221; 0.4%), RVA + RVC (1/221; 0.4%), and RVB + RVC (1/221; 0.4%) was identified in fecal samples. The results demonstrated a significant increase in the RVC and, mainly, RVB detection rates in single infections. This study allowed us to characterize the importance of other RV species, in addition to RVA, in the etiology of neonatal diarrhea in piglets from pig herds with a regular vaccination program for RVA diarrhea control and prophylaxis., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

The role of Mycoplasma bovirhinis in the development of pulmonary disease in cattle is controversial and was never evaluated in cattle from Latin America. This study investigated the respiratory infection dynamics associated with M. bovirhinis in suckling calves from 15 dairy cattle herds in Southern Brazil. Nasal swabs were obtained from asymptomatic ( n = 102) and calves with clinical manifestations ( n = 103) of bovine respiratory disease (BRD) and used in molecular assays to identify the specific genes of viral and bacterial disease pathogens of BRD. Only M. bovirhinis , bovine coronavirus (BCoV), ovine gammaherpesvirus 2 (OvGHV2), Histophilus somni , Pasteurella multocida , and Mannheimia haemolytica were detected. M. bovirhinis was the most frequently diagnosed pathogen in diseased (57.8%; 59/102) and asymptomatic (55.3%; 57/103) calves at all farms. BCoV-related infections were diagnosed in diseased (52%; 53/102) and asymptomatic (51.4%; 53/103) calves and occurred in 93.3% (14/15) of all farms. Similarly, infectious due to OvGHV2 occurred in diseased (37.2%; 38/102) and asymptomatic (27.2%; /28/103) calves and were diagnosed in 80% (12/15) of all farms investigated. Significant statistical differences were not identified when the two groups of calves were compared at most farms, except for infections due to OvGHV2 that affected five calves at one farm. These results demonstrated that the respiratory infection dynamics of M. bovirhinis identified in Southern Brazil are similar to those observed worldwide, suggesting that there is not enough sufficient collected data to consider M. bovirhinis as a pathogen of respiratory infections in cattle. Additionally, the possible roles of BCoV and OvGHV2 in the development of BRD are discussed.

Bovine viral diarrhea virus (BVDV), bovine alphaherpesvirus 1 (BoAHV1), bovine respiratory syncytial virus (BRSV), and bovine parainfluenza virus 3 (BPIV-3) are involved in bovine respiratory disease. These viruses can infect the respiratory system and cause considerable economic losses to beef and dairy cattle herds. This study aimed to determine the serological profiles of steers for BVDV, BoAHV1, BRSV, and BPIV-3 upon their arrival at Brazilian feedlot facilities. A total of 1,282 serum samples from unvaccinated steers were obtained on the first day of feeding. Samples were collected from 31 beef cattle herds reared in an extensive rearing system in six Brazilian states. Antibodies against BVDV, BoAHV1, BRSV, and BPIV-3 were detected using a virus neutralization test. The steers were distributed in agreement with their age and the Brazilian state of origin. The highest seropositivity was for BoAHV1 and BPIV-3 at 92.1% (1,154/1,253) and 86.6% (1,100/1,270), respectively. The seropositivity of BRSV was 77.1% (959/1,244). BVDV presented a lower rate, at slightly more than 50% (51.8%; 656/1,266). Age was a risk factor for the presence of antibodies against BVDV, BoAHV1, and BPIV-3 but not BRSV. A positive correlation was identified between BoAHV1 and BPIV-3 (P = 0.85) and between BRSV and BPIV-3 (P = 0.47). The high rate of seropositive steers for these four respiratory viruses on the first day of confinement identified in this serological survey provides important epidemiological information on respiratory infections, as the seropositivity of the four main bovine respiratory viruses in Brazilian beef cattle herds in an extensive rearing system., (© 2023. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Bovine respiratory disease (BRD) is a multifactorial and predominantly multietiological disease that affects dairy cattle herds worldwide, being more frequent in young animals. The occurrence of BRD was investigated in lactating cows from two high-yielding dairy herds in southern Brazil. To determine the etiology of the clinical cases of acute respiratory disease, nasal swab samples were collected from cows with clinical signs of BRD and evaluated using PCR and RT-PCR for nucleic acid detection of the main BRD etiological agents, including Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, bovine respiratory syncytial virus, bovine coronavirus, bovine viral diarrhea virus, bovine alphaherpesvirus 1, and bovine parainfluenza virus 3. Only three microorganisms (M. bovis, H. somni, and P. multocida) were identified in both single and mixed infections. We concluded that 40.0% of the cows were infected with M. bovis and 75.0% with H. somni in herd A. Considering both single and mixed infections, the analyses performed in herd B showed that 87.5%, 25.0%, and 50.0% of the cows were infected with M. bovis, H. somni, and P. multocida, respectively. M. bovis and H. somni are considered fastidious bacteria and laboratory diagnosis is neglected. Subsequently, most clinical cases of mycoplasmosis and histophilosis in cattle remain undiagnosed. This study demonstrates the importance of M. bovis and H. somni infections in adult cows with BRD. These results highlight the importance of including these bacteria in the group of etiological agents responsible for the occurrence of BRD in cattle, especially in adult cows with unfavorable immunological conditions, such as recent calving and peak lactation., (© 2023. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

We evaluated the presence of antibodies against CaHV-1, CDV, and CPV-2 in serum samples from Brazilian wild carnivore species. Nine maned wolves and six crab-eating foxes were tested for CaHV-1 and CDV by virus neutralization test and CPV-2 by hemagglutination inhibition assay. Antibodies to CaHV-1, CDV, and CPV-2 were detected in serum samples of 1 (6.7%), 5 (33.3%), and 10 (66.7%) wild carnivores, respectively. Two maned wolves and one crab-eating fox were seropositive simultaneously for CDV and CPV-2. Antibodies against all viruses were detected in one crab-eating fox. This is the first report of CaHV-1 antibody detection in crab-eating foxes., (© 2023. EcoHealth Alliance.)

This report investigated the cause of cattle mortality in two farms in Southern Brazil. The tissues of one animal from each farm (animals #1 and #2) respectively were used in pathological and molecular investigations to determine the possible cause of death. The principal pathological findings observed in animal #1 were pulmonary, myocardial, and encephalitic hemorrhages with vasculitis, and lymphoplasmacytic interstitial pneumonia with proliferative vascular lesions (PVL). The main pathological findings observed in animal #2 were purulent bronchopneumonia, hemorrhagic myocarditis, and lymphoplasmacytic interstitial pneumonia with PVL. An immunohistochemical assay detected intralesional antigens of a malignant catarrhal fever virus (MCFV) from multiple tissues of animal #2 while PCR confirmed that the MCFV amplified was ovine gammaherpesvirus 2 (OvGHV2), genus Macavirus, subfamily Gammaherpesvirinae; OvGHV2 was also amplified from multiple tissues of animal #1. Furthermore, PCR assays amplified Histophilus somni DNA from multiple fragments of both animals. However, the nucleic acids of Mannheimia haemolytica, Pasteurella multocida, Mycoplasma bovis, bovine respiratory syncytial virus, bovine alphaherpesvirus virus 1 and 5, bovine coronavirus, and bovine parainfluenza virus 3 were not amplified from any of the tissues analyzed, suggesting that these pathogens did not participate in the development of the lesions herein described. These findings demonstrated that both animals were concomitantly infected by H. somni and OvGHV2 and developed the septicemic and encephalitic manifestations of H. somni. Furthermore, the interstitial pneumonia observed in cow #2 was more likely associated with infection by OvGHV2., (© 2023. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Seneca Valley virus (SVV) is the only representative member of the Senecavirus genus of the Picornaviridae family. Since 2014, SVV has been identified as a causative agent of vesicular disease outbreaks in pigs of different ages from Brazil, the USA, Canada, China, Thailand, Colombia, Vietnam, and India. From May 2020, several pig herds, from the Brazilian states Parana and Santa Catarina reported vesicular disease in different pig categories. This study aimed to report the third wave of SVV outbreaks in pig herds in southern Brazil. A total of 263 biological samples from 150 pigs in 18 pig herds were evaluated. The samples were obtained from pigs with clinical signs of vesicular disease (n = 242) and asymptomatic animals (n = 21). Seneca Valley virus RNA was detected in 96 (36.5%) of the biological samples evaluated, with 89 samples from symptomatic and 7 from asymptomatic pigs. The data show that asymptomatic pigs, but in viremia, are possible sources of infection and can act as carriers and possibly spreaders of SVV to the herd. In this study, we report the third wave of vesicular disease outbreaks caused by SVV in different categories of pigs from herds located in southern Brazil., (© 2022. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Bovine respiratory disease (BRD) is considered a major cause of morbidity and mortality in young calves and is caused by a range of infectious agents, including viruses and bacteria. This study aimed to determine the frequency of viral and bacterial pathogens detected in calves with BRD from high-production dairy cattle herds and to perform the molecular characterization of N and S1 genes in identified bovine coronavirus (BCoV) strains. Nasal swabs were collected from 166 heifer calves, namely, 85 symptomatic and 81 asymptomatic calves aged between 5 and 90 days, from 10 dairy cattle herds. Nasal swabs were evaluated using molecular techniques for the identification of viruses (BCoV, bovine alphaherpesvirus 1, bovine viral diarrhea virus, bovine parainfluenza virus 3, and bovine respiratory syncytial virus) and bacteria ( Pasteurella multocida, Mannheimia haemolytica, Histophilus somni , and Mycoplasma bovis ). In addition, five and two BCoV-positive samples were submitted to N and S1 gene amplification and nucleotide sequencing, respectively. The frequency of diagnosis of BCoV was higher (56%, 93/166) than the frequency of P. multocida (39.8%, 66/166) and M. haemolytica (33.1%, 55/166). The three microorganisms were identified in the calves of symptomatic and asymptomatic heifer calve groups. All other pathogens included in the analyses were negative. In the phylogenetic analysis of the S1 gene, the Brazilian strains formed a new branch, suggesting a new genotype, called # 15; from the N gene, the strains identified here belonged to cluster II. This study describes high rates of BCoV, P. multocida , and M. haemolytica in heifer calves from high-production dairy cattle herds with BRD. Additionally, the molecular characterization provides evidence that the circulating BCoV strains are ancestrally different from the prototype vaccine strains and even different BCoV strains previously described in Brazil., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Frucchi, Dall Agnol, Bronkhorst, Beuttemmuller, Alfieri and Alfieri.)

Feline Morbillivirus (FeMV) was first detected in 2012 in domestic cats from Hong Kong and was found to be associated with tubulointerstitial nephritis and chronic kidney disease. In subsequent studies in other countries, FeMV was detected in asymptomatic cats. However, it is not clear whether FeMV plays a role as a pathogen in the kidney diseases of cats, and other epidemiological data are still unknown. To date, studies have reported the presence of FeMV exclusively in domestic cats. This study is the first molecular detection of the FeMV RNA associated with pathological and immunohistochemical findings in a synanthropic marsupial, the white-eared opossum (Didelphis albiventris), inhabiting peri-urban areas of north-central Parana, Southern Brazil. Molecular techniques identified the viral RNA in the lungs and kidneys. Histopathologic evaluation of these tissues revealed interstitial pneumonia in the lungs with lymphocytic nephritis and tubular necrosis in the kidneys. Immunohistochemistry assays detected positive intralesional immunoreactivity to N protein of FeMV within the lungs and kidneys. A FeMV opossum strain was isolated in Crandell Rees feline kidney lineage cells, resulting in syncytia formation and cell death. Therefore, these results support the ability of FeMV to infect other mammal species and reinforce the possibility of the opossum to be a disseminator of this virus among domestic and wild animals., (© 2021 Wiley-VCH GmbH.)

This study describes the etiological diversity observed in a severe neonatal diarrhea outbreak with morbidity and mortality rates of 80 and 20%, respectively, with detection of mixed infections with viral, bacterial, and protozoan disease agents in a dairy calf rearing unit. Diarrheic fecal samples were collected from eight 5 to 18 days of age calves and were submitted to the investigation of the presence of rotavirus A (RVA), bovine coronavirus (BCoV), bovine kobuvirus (BKV), bovine viral diarrhea virus 1 and 2 (BVDV-1 and BVDV-2), enteropathogenic Escherichia coli (ETEC), Salmonella sp., and Cryptosporidium spp. Fragments of the small intestine of one calf with diarrhea that spontaneously died were submitted for histopathological analyses. The most frequent infectious agent detected in diarrheic fecal samples was BKV (8/8-100%), followed by RVA (5/8-62.5%), BVDV (5/8-62.5%), Cryptosporidium parvum (5/8-62.5%), ETEC (4/8-50%), and Cryptosporidium ryanae (1/8-12.5%). These etiological agents were found in mixed infections with two or more pathogens per diarrheic fecal sample. The association of viral and protozoan pathogens was the most frequently identified (37.5%) in these samples, followed by viral and bacterial (25%); viral, bacterial, and protozoan (25%); and only viral agents (12.5%). BCoV and Salmonella sp. were not identified in the diarrheic fecal samples analyzed. Additionally, histopathology of the small intestine diagnosed chronic lymphocytic enteritis. In conclusion, in calf rearing units, the adoption and strict monitoring of health management practices are critical to the success of this calf creation system., (© 2021. Sociedade Brasileira de Microbiologia.)

Background: Suid gammaherpesvirus 3 , 4 , and 5 (porcine lymphotropic herpesvirus - PLHV-1, -2, and -3) are viruses that infect domestic and feral pigs., Objectives: This study examined the presence of PLHV DNA in biological samples from free-living wild boars circulating in a Brazilian geographical region with a high density of commercial domestic pigs., Methods: Lung samples of 50 free-living wild boars were collected by exotic wildlife controller agents between 2017 and 2019 in the state of Paraná, southern Brazil. Lung and spleen fragments were obtained from six fetuses collected by hysterectomy post mortem from a pregnant sow. A polymerase chain reaction (PCR) assay using consensus primers (pan-herpesviruses) was performed to detect PLHV DNA. The samples showing positive results for PLHV DNA were submitted to single-round PCR assays with the specific primers for identifying PLHV-1 (213-S/215-As), PLHV-2 (208-S/212-As), and PLHV-3 (886s/886As). The specificity of the species-specific PCR products was assessed by nucleotide sequencing of the amplicons., Results: Forty-eight (96%) of the 50 lung samples analyzed were positive for PLHV by PCR using pan-herpesvirus primers. In 33 (68.75%) of the positive samples, at least two PLHV species were identified simultaneously. The DNA of PLHV-1, -2, and -3 was found in free-living wild boars of all ages, but not in the fetuses, even though they were from a sow that tested positive for all three viruses., Conclusion: These viruses are endemic to the population of feral pigs in the Brazilian region evaluated, as well as in domesticated pigs., Competing Interests: The authors declare no conflicts of interest., (© 2021 The Korean Society of Veterinary Science.)

We describe the molecular analysis of a wild-type field strain of bovine viral diarrhea virus (BVDV) identified in a mummified fetus from a small Brazilian dairy cattle herd. Nucleic acids extracted from samples of the lung, liver, heart, spleen, and kidney were tested by PCR assays for bovine alphaherpesvirus 1, Neospora caninum , Leptospira spp., Histophilus somni , and Brucella abortus , a nested PCR assay for Mycoplasma bovigenitalium and Ureaplasma diversum , and a RT-PCR assay for BVDV. Amplicons were only obtained in the RT-PCR assay for the partial amplification of the BVDV 5'UTR (288 bp) in kidney and spleen samples and the N pro (438 bp) gene in the kidney sample. Nucleotide sequencing of the amplified products and phylogenetic analyses based on the 2 BVDV genomic regions enabled the BVDV strain to be classified as subgenotype 1a.

Bovine viral diarrhea virus (BVDV) is a major pathogen in cattle herds. Considering the epidemiological importance of pestiviruses and the process of wild boar invasion in Brazil, this study aimed to investigate the presence of BVDV in free-living boars. Forty-nine free-living wild boars were collected by exotic wildlife controller agents in 2017 and 2018. The presence of BVDV antibodies was evaluated in 42 serum samples using the virus neutralization test, and the detection of BVDV RNA was performed from the 5'UTR genomic region by RT-PCR assay in 49 lung tissue samples followed by sequencing of amplicons. BVDV neutralizing antibodies in serum were not identified in any of the evaluated samples. However, 3/49 (6.12%) lung samples were positive for BVDV RNA and classified one as BVDV-1a and two as 1d subgenotype. This report identified BVDV RNA in free-living wild boars and these results should be considered in BVDV control programs, especially in extensive beef cattle rearing systems.

This study is aimed at detecting Feline paramyxovirus (FPaV) and Feline morbillivirus (FeMV) in 35 urine samples from domestic cats, collected in 2019, with or without clinical signs of uropathies using a reverse transcription-polymerase chain reaction (RT-PCR) followed by semi-nested polymerase chain reaction (SN-PCR) assays to amplify a partial paramyxovirus L gene. Eight (22.9%) out of the 35 urine samples were positive for paramyxoviruses. Sequencing and phylogenetic analyses revealed that three samples were positive for FPaV, four samples were positive for FeMV, and it was not possible to determine which virus was present in one RT-SN-PCR positive urine sample. FPaV strains showed 100% nucleotide (nt) identity with each other and 97% nt identity with a Japanese 163 FPaV strain. The FeMV strains showed 85.9% nt identity with each other; three strains were similar to previously described Brazilian FeMV strains, and one strain clustered in a different branch of the phylogenetic tree together with the first described Chinese FeMV strain. This study provides the first description of FPaV strains in cats from Brazil and provides new information about the molecular characteristics of FPaV and FeMV strains circulating in domestic cats in Brazil.

Bovine papillomavirus types 2 and 13 can induce tumors in both the cutaneous and mucosal epithelia of cattle. These viral types are associated with the development of benign cutaneous papillomas and malignant lesions in the urinary bladders of cattle, with the latter being known as bovine enzootic hematuria. Among the viral oncoproteins encoded by Deltapapillomavirus DNA, the E6 oncoprotein has an important role in cell proliferation and might be related to cancer initiation and promotion. The aim of this study was to present a standardized SYBR Green-based quantitative PCR for detection and quantification of the bovine papillomavirus 2 and 13 E6 oncogenes in urinary bladder samples from cattle. Twenty-four urinary bladders from cattle displaying tumors ( n = 12) and normal bladder mucosa ( n = 12) were tested by quantitative PCR. Of the 12 urinary bladders with tumors, six presented bovine papillomavirus 2 DNA concentrations ranging from 1.05 × 10 4 to 9.53 × 10 3 copies/μL, while two had bovine papillomavirus 13 DNA amplified at concentrations of 1.30 × 10 4 to 1.23 × 10 4 copies/μL. The healthy bladder mucosa samples were negative for both bovine papillomaviruses. Once the results were confirmed by conventional PCR and direct sequencing, the quantitative PCR assay developed in this study was shown to be a sensitive and specific tool for detecting and quantifying the E6 ORF of bovine papillomavirus 2 and 13 in a variety of clinical samples. Our findings of identification of bovine papillomavirus 2 and 13 DNA in urothelial tumors from cattle suffering from bovine enzootic hematuria agree with data from previous studies, representing the first detection of bovine papillomavirus 13 DNA in malignant bladder lesions of cattle from Brazil., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Alcântara, Lunardi, Agnol, Alfieri and Alfieri.)

The crab-eating fox (Cerdocyon thous) is a small wild mammal present in all Brazilian biomes and in some countries of South America. This study aimed to verify the involvement of viral infectious agents in the death of a wild crab-eating fox pup (Cerdocyon thous) in Brazil. The Center for Medicine and Research of Wild Animals of the Universidade Estadual Paulista received a free-living crab-eating fox aged approximately 21 days and apparently healthy. After 13 days, the animal presented anorexia, diarrhea, fever, prostration, and neurological signs progressing to death with an inconclusive diagnosis. In a retrospective study, tissue fragments stored at - 80 °C were used to identify nucleic acids from major canine viruses, such as canine parvovirus-2 (CPV-2), canine adenovirus A types 1 and 2, canid alphaherpesvirus 1, and canine distemper virus. The amplified product with the expected length for CPV-2 was obtained from the heart fragment. After performing nucleotide (nt) sequencing of the amplicon, it was possible to demonstrate that the crab-eating fox strain exhibited high (99.8%) nt identity with the CPV-2b prototype (CPV-39 strain). Additionally, deduced amino acid (aa) sequence analysis showed the GAT codon for the aa Asp (D) at position 426 of the CPV-2 viral protein VP2, which characterizes the subtype 2b. To the best of the authors' knowledge, this report describes the first detection of CPV-2b DNA in tissue fragments from a crab-eating fox.

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 wild-type 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  = 3) in 2011 and steers of three other feedlots ( n  = 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.

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.

The reports of rotavirus C (RVC) involvement in diarrhea outbreaks in newborn piglets have been increasing in recent years. This longitudinal study, conducted over a 37-day period, aimed to evaluate the frequency of RVC infection in piglets aged up to 7 days obtained from a pig herd with a previous diagnosis of RVC infection in this age group. Piglets from 50 different litters were monitored daily for the occurrence of diarrhea, and all litters were classified into the following categories: sow parity order (PO) 1 to 5; litter size (LS) ≤ 10 piglets and > 10 piglets; and piglet birth weight (BW) 1.2 to 1.3 kg and > 1.3 to 1.4 kg. Two hundred six diarrheic fecal samples were collected and classified according to the fecal consistency score (pasty, semiliquid, liquid). Ten fecal samples were collected from asymptomatic piglets (control group). Fecal samples were screened for rotavirus (RV) by silver stained-polyacrylamide gel electrophoresis (ss-PAGE), and samples with inconclusive and negative-ss-PAGE results were submitted to RVC VP6 gene amplification by RT-PCR. RVC was identified in 71 (34.5%) samples, in 1 (10%) sample of the control group, and in piglets from 33 (66%) litters. The electrophoretic profile of RV species A was identified in only two samples. Of the 72 RVC-positive samples, 51 (70.8%) presented semiliquid or liquid consistency. There was no significant difference in either group regarding the production parameters (PO, LS, BW) evaluated. An analysis of the whole VP6 gene of three RVC field strains collected on the first, fifteenth, and last day of the experiment enabled us to identify genotype I6. This report describes the first longitudinal study examining epidemiological aspects of RVC infection in newborn piglets.

Canine parvovirus type 2 (CPV-2) is classified into three subtypes (CPV-2a, CPV-2b, and CPV-2c) and is the main cause of enteritis and myocarditis in young domestic and wild animals. This study aimed to evaluate the presence of CPV-2 in the feces of asymptomatic free-living coatis from Garden Forest Reserve, Palmital city, SP, Brazil. Fecal samples from 21 coatis (both sexes, different ages, and different aspects of feces) were collected in August 2014 and March 2015. The nucleic acid extracted was submitted to a polymerase chain reaction (PCR) assay to amplify a fragment of the VP2 gene of CPV-2. Eight (38%) fecal samples were positive in the PCR assay and were confirmed by sequencing. The 7 nucleotide (nt) sequences analyzed showed 100% nt identity with the prototype strain of CPV-2b (CPV-39 strain). The analysis of the deduced amino acid (aa) sequence revealed the presence of the GAT codon (aa D-Asp) at position 426 of the VP2 viral protein (subtype 2b). This study describes for the first time the identification of CPV-2b in asymptomatic free-living coatis (Nasua nasua) and suggests that coatis are susceptible to Carnivore protoparvovirus 1 infection and are important as a reservoir and an asymptomatic carrier to other wild and domestic animal species.

Among reproductive disorders in dairy and beef cattle worldwide, embryonic mortalities stand out as one of the most frequent. Because of the multifactorial etiology, the clinical and laboratory diagnoses of embryonic mortality causes in cattle are quite complex. Often, infectious causes may account for up to 50% of bovine embryonic mortality rates after 30 days of conception. This review will address the main causes of early and late embryonic mortality, with emphasis on infectious causes and, particularly, those more frequent in the Brazilian cattle herds. In addition, we will discuss ways of controlling and prophylaxis including those related to reproductive and sanitary management, with emphasis on immunoprophylaxis of the three most frequent reproductive infectious diseases in Brazilian dairy and beef cattle herds., Competing Interests: Conflict of interest
The authors declared no potential conflicts of interest relative to the research, authorship, and/or publication of this article., (Copyright © The Author(s). Published by CBRA.)

Currently, bovine papillomavirus types are divided into five genera, namely, Deltapapillomavirus, Epsilonpapillomavirus, Xipapillomavirus, Dyoxipapillomavirus, and Dyokappapapillomavirus. In the recent decades, the characterization of numerous putative and novel bovine papillomavirus types from cattle in several geographic regions, has revealed the occurrence of a high viral diversity. In this study, we describe the identification and characterization of a putative new bovine papillomavirus type within species Xipapillomavirus 1 of Xipapillomavirus genus. The detection of the viral types identified in the skin warts was obtained by polymerase chain reaction assays targeting the L1 gene, followed by direct sequencing of the generated amplicons. The partial L1 sequences revealed that bovine papillomavirus types 6, 10, and 11, the putative new bovine papillomavirus type designated BPV/CHI-SW2, and an unreported putative new bovine papillomavirus type (named BPV/BR-UEL08) were associated with cutaneous papillomatosis in the cows from the dairy herd investigated. Phylogenetic reconstruction based on the L1 gene revealed that the BPV/BR-UEL08 isolate clustered with other bovine papillomaviruses classified in the Xipapillomavirus genus, being closely related to representatives of the species Xipapillomavirus 1. Investigations focusing on the molecular epidemiology of bovine papillomaviruses related to clinical outcomes in cattle are of fundamental importance to determine the actual genetic diversity and prevalent viral types to be included in vaccines for cattle.

Canine kobuvirus (CaKV) is a member of the Picornaviridae family and the Kobuvirus genus. CaKV was first described in fecal samples from diarrheic dogs in the USA in 2011, with subsequent reports in the UK, Italy, South Korea, China, Tanzania, and Japan. CaKV is frequently identified in feces of animals with or without clinical signs of gastroenteritis. The present study investigated the presence of CaKV in fecal samples from 53 diarrheic dogs from Londrina, southern Brazil. Using a RT-PCR assay, CaKV RNA was identified in three dogs, resulting in an overall occurrence rate of 5.7%. In addition, coinfection with canine parvovirus subtype 2b was detected in all CaKV-positive diarrheic fecal samples. Using a phylogenetic analysis based on the VP1 gene sequence, the Brazilian CaKV field strains were found to be very similar to a previously identified CaKV strain from Brazil that was found in the tissue of a puppy and were also found to be clustered with other CaKV strains detected worldwide and other kobuvirus strains identified in mouse, feline, and human hosts.

Equid gammaherpesvirus 2 (EHV-2) and 5 (EHV-5) are members of the Herpesviridae family and have been reported in horse populations worldwide. This study aimed to evaluate the presence of herpesvirus DNA in the upper respiratory tract of horses. Twenty-six nasal swabs were collected from asymptomatic adult horses of two different horse farms (A, n = 18; B, n = 8), both located in Southern Brazil. The EHV-1, EHV-2, EHV-4, and EHV-5 DNA analyses were performed using nested PCR assays targeting the glycoprotein B gene. Four (15.3%) and 12 (46.1%) of the 26 nasal swab samples were positive for the EHV-2 and EHV-5, respectively. Four (15.3%) horses were detected with both viruses simultaneously. DNA of EHV-2 and EHV-5 in both single and mixed infections was identified in horses from both herds. All swab samples were negative for EHV-1 and EHV-4. This study reports the first detection of EHV-2 and EHV-5 in the upper respiratory tracts of horses in Brazil. The high detection rate of EHV-2 and EHV-5 in asymptomatic adult horses demonstrates that these gammaherpesviruses are circulating in Brazil.

Neonatal diarrhea is the main cause of morbidity and mortality in calves up to 30 days old, and rotavirus A (RVA) is the main viral etiology. RVA vaccines are one of the main tools for diarrhea control in neonates. The aim of this cross-sectional study was to monitor by RT-PCR the G and P genotypes of RVA strains identified in dairy cattle herds regularly vaccinated with the RVA UK strain (G6P[5]). Of the 14 randomly selected herds, two were excluded because no calf was diagnosed with diarrhea on the day of fecal collection. Another six herds were also excluded from the study because all 20 diarrheic fecal samples evaluated were RT-PCR-negative. In the remaining six herds, 17 (25.4%) of the 67 diarrheic samples were RVA-positive. One G and P amplicon from each herd were selected for nucleotide sequencing. In the phylogenetic analysis, five RVA strains presented the G6P[11] genotype, and one presented the G10P[11] genotype. The G6 genotype present in all RVA field strains clustered into a distinct phylogenetic arrangement (lineage III) of the UK vaccine strain (lineage IV), characterizing the emergence of a phylogenetically distant G6 strain. In addition, we observed the emergence of strains with G10 and P[11] genotypes characterizing failure in heterologous immune protection. These results show the epidemiological importance of constant monitoring of RVA strains in vaccinated cattle herds and the low frequencies of diarrhea and diagnosis of RVA suggest that a regular vaccination program reduces the frequency and severity of RVA diarrhea in suckling calves.

Fecal samples from 27 pigs were longitudinally analyzed for Teschovirus A (TV-A), Sapelovirus A (SV-A), and Enterovirus G (EV-G) RNA presence. Suckling piglet fecal samples were negative for the three enteric picornaviruses. However, these picornaviruses were detected in 22/27 weaned pig fecal samples. This study provides new data on TV-A, SV-A, and EV-G infection dynamics.

Dairy calf rearing unit is a management system that is only recently being implemented by some milk producer's cooperatives in southern Brazil. However, aspects related to the health profile of the heifer calves that arrive in the rearing unit as well as about biosecurity practices and microbiological challenges have not yet been evaluated in this rearing system in a tropical country. Diarrhea is the main and most frequent consequence of enteric infections in newborn calves. This study, through some etiological and epidemiological characteristics of an outbreak of neonatal diarrhea, has the aim to alert to the possibility of pathogenic microorganism spread in a dairy heifer calf rearing unit. The diarrhea outbreak presented some non-regular characteristics observed in bovine coronavirus (BCoV) enteric infections in dairy calves. The spread of infection was extremely rapid (1 week); the attack rate (> 50%) was much higher than that observed in calves subjected to conventional rearing; and the age range (5 to 90 days) of the affected heifer calves was much broader than that often observed in the BCoV diarrhea worldwide. These unusual epidemiological characteristics observed in this BCoV diarrhea outbreak raise awareness of the health threat present in calf rearing units as well as of the easy and rapid viral spread in a population of young animals from different dairy herds and, therefore, with very distinct immunological status.

Serological studies have characterized the presence of the bovine viral diarrhea virus (BVDV) infection in water buffalo herds worldwide. However, the molecular characterization of BVDV strains circulating in this animal species is uncommon. The aim of this study was to identify young water buffalo with acute infection and characterize the subgenotype of the infecting wild-type BVDV strain. Two dairy water buffalo herds from Northeastern Brazil were selected based on the results of virus neutralization test which showed high titers of anti-BVDV antibodies. To identify viremic animals, the BVDV RNA was assessed by RT-PCR assay in serum samples from 44 asymptomatic young water buffalos, where 31 serum samples from herd A and 13 from herd B. Amplicons with 288 bp of BVDV 5'UTR region were obtained in 7 (15.9%) serum samples (herd A, n = 5; herd B, n = 2). One good-quality amplicon from each herd was selected for nucleotide sequencing. The phylogenetic analysis demonstrated that the two BVDV wild-type strains clustered with BVDV strains of the subgenotype 1b. This study identified for the first time the active infection by BVDV subgenotype 1b in two dairy water buffalo herds from Brazil. These results highlight the importance of that, as well as in cattle herds, also in water buffalo herds prophylaxis measures to control BVDV infection should be intensified, mainly because these species clearly coexist in buffalo farms within Brazil.

Histophilus somni is a Gram-negative bacterium that is associated with a disease complex (termed histophilosis) that can produce several clinical syndromes predominantly in cattle, but also in sheep. Histophilosis is well described in North America, Canada, and in some European countries. In Brazil, histophilosis has been described in cattle with respiratory, reproductive, and systemic disease, with only one case described in sheep. This report describes the occurrence of Histophilus somni-associated disease in sheep from Southern Brazil. Eight sheep with different clinical manifestations from five farms were investigated by a combination of pathological and molecular diagnostic methods to identify additional cases of histophilosis in sheep from Brazil. The principal pathological lesions were thrombotic meningoencephalitis, fibrinous bronchopneumonia, pulmonary abscesses, and necrotizing myocarditis. The main clinical syndromes associated with H. somni were thrombotic meningoencephalitis (n=4), septicemia (n=4), bronchopneumonia (n=4), and myocarditis (n=3). H. somni DNA was amplified from multiple tissues of all sheep with clinical syndromes of histophilosis; sequencing confirmed the PCR results. Further, PCR assays to detect Pasteurella multocida and Mannheimia haemolytica were negative. These findings confirmed the participation of H. somni in the clinical syndromes investigated during this study, and adds to the previous report of histophilosis in sheep from Brazil., (Copyright © 2018 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.)

Canine parvovirus (CPV) is a fast-evolving single-stranded DNA virus that causes one of the most significant infectious diseases of dogs. Although the virus dispersed over long distances in the past, current populations are considered to be spatially confined and with only a few instances of migration between specific localities. It is unclear whether these dynamics occur in South America where global studies have not been performed. The aim of this study is to analyze the patterns of genetic variability in South American CPV populations and explore their evolutionary relationships with global strains. Genomic sequences of sixty-three strains from South America and Europe were generated and analyzed using a phylodynamic approach. All the obtained strains belong to the CPV-2a lineage and associate with global strains in four monophyletic groups or clades. European and South American strains from all the countries here analyzed are representative of a widely distributed clade (Eur-I) that emerged in Southern Europe during 1990-98 to later spread to South America in the early 2000s. The emergence and spread of the Eur-I clade were correlated with a significant rise in the CPV effective population size in Europe and South America. The Asia-I clade includes strains from Asia and Uruguay. This clade originated in Asia during the late 1980s and evolved locally before spreading to South America during 2009-10. The third clade (Eur-II) comprises strains from Italy, Brazil, and Ecuador. This clade appears in South America as a consequence of an early introduction from Italy to Ecuador in the middle 1980s and has experienced extensive local genetic differentiation. Some strains from Argentina, Uruguay, and Brazil constitute an exclusive South American clade (SA-I) that emerged in Argentina in the 1990s. These results indicate that the current epidemiological scenario is a consequence of inter- and intracontinental migrations of strains with different geographic and temporal origins that set the conditions for competition and local differentiation of CPV populations. The coexistence and interaction of highly divergent strains are the main responsible for the drastic epidemiological changes observed in South America in the last two decades. This highlights the threat of invasion from external sources and the importance of whole-genome resolution to robustly infer the origin and spread of new CPV variants. From a taxonomic standpoint, the findings herein show that the classification system that uses a single amino acid to identify variants (2a, 2b, and 2c) within the CPV-2a lineage does not reflect phylogenetic relationships and is not suitable to analyze CPV evolution. In this regard, the identification of clades or sublineages within circulating CPV strains is the first step towards a genetic and evolutionary classification of the virus.

Serological evidence shows that the bovine viral diarrhea virus (BVDV) infections are present in Brazilian dairy and beef water buffalo herds. As few reports describe the BVDV infection profile the aim of this study was to evaluate the dynamics of BVDV circulation in Brazilian dairy water buffalo herds through analysis of the seropositivity rate and the titer range of anti-BVDV neutralizing antibodies in a group of animals that are considered sentinels. Blood samples (n = 305) were obtained from unvaccinated, asymptomatic young water buffalos from four dairy herds randomly identified as A (n = 106), B (n = 62), C (n = 119), and D (n = 18). The detection and titration of anti-BVDV neutralizing antibodies were evaluated by the virus neutralization test according to the World Organization for Animal Health. Analysis of the results revealed two distinct epidemiological conditions. The first is represented by herds A and C where high rates of seropositive animals (A = 39.6%; C = 51.3%) and high and very variable antibodies titers suggested active BVDV infection. The other condition is represented by herds B and D with low rates of seropositive animals (B = 8.1%; D = 11.1%) and low and little variable antibodies titers suggesting an epidemiological condition of infection stability. Some variables were observed in herds with a distinct BVDV infection profile. Herds with active infection were big, open herds, and had more management practices. In contrast, the herds with infection stability were small, closed herds with few management practices. These results highlight the importance of evaluation, monitoring, and control of BVDV infection also in dairy water buffalo herds.

Rotaviruses (RVs), a common cause of viral gastroenteritis in humans and animals, are classified into 9 established groups/species (RVA-RVI). Although RVB has been found in several countries, genetic variation among RVB field strains remains poorly characterized. RVB strains can be classified into G genotypes based on a nucleotide (nt) homology that exceeds a cutoff value of 80% for the gene that encodes the structural protein VP7. In this study, we determined the VP7 nt and deduced amino acid sequences of one RVB strain (RB62) identified in a diarrheic fecal sample obtained from a piglet in Brazil in 2012. Comparative analysis of this strain and the strains of the other 21 previously identified VP7 ge-notypes showed that the highest nt identity (71.2%) was found with the porcine PB-70-H5 strain within the G4 genotype. However, when compared with the nonclassified Vietnamese RVB G genotype 14177_18 strain, the nt sequence identity was of 82.9%. These results led us to conclude that the Brazilian strain BR62 and the Vietnamese strain 14177_18 belong to a novel G genotype (G22)., (© 2018 S. Karger AG, Basel.)

Seneca Valley virus (SVV) is the etiological agent of vesicular disease in pigs, clinically indistinguishable of classical viral vesicular infections, including foot-and-mouth disease. The first outbreaks of SVV infection in Brazil were reported in 2014. However, it was not known whether the virus was circulating in Brazilian pig herds before this year. This study is a retrospective serological investigation of porcine health status to SVV in Brazil. Serum samples (n = 594) were grouped in before (2007-2013, n = 347) and after (2014-2016, n = 247) SVV outbreaks in Brazil. Twenty-three pig herds were analyzed, of which 19 and 4 were sampled before and after the beginning of SVV outbreaks, respectively. Two herds sampled after 2014 presented animals with SVV-associated clinical manifestations, while the other two housed asymptomatic pigs. Anti-SVV antibodies were evaluated by virus neutralization test. The results demonstrated that pig herds of different Brazilian geographical regions and distinct pig categories were negative to anti-SVV antibodies in sera obtained before 2014. Antibodies to SVV were detected only in serum samples obtained after 2014, particularly in herds with the presence of pigs with SVV-clinical signs. These results present robust serological evidence that the SVV was not present in the major Brazilian pig producing regions prior to 2014.

This report describes the identification of an unusual G26P[13] genotype combination in a porcine group A rotavirus (RVA) strain. In a retrospective study, the VP7 (G type) and VP4 (P type) genes of porcine RVA Brazilian field strains identified in two diarrheic suckling piglets were amplified by RT-PCR and subjected to sequencing. The sequence analysis revealed the G26P[13] RVA genotype in one strain (BRA381) and G26P[X] in the other (BRA382). This study presents evidence of porcine RVA G26 genotype circulating in a Brazilian pig herd.

Worldwide diarrhea outbreaks in cattle herds are more frequently detected in calves being that diarrhea outbreaks in adult cattle are not common. Winter dysentery (WD) is a bovine coronavirus (BCoV) enteric infection that is more reported in Northern hemisphere. Seasonal outbreaks of WD in adult cattle occur mainly in dairy cows. WD has not been described in beef cattle herds of tropical countries. This study describes the molecular detection of BCoV in a diarrhea outbreak in beef cattle steers (Nellore) raised on pasture in Parana, southern Brazil. During the outbreak, the farm had about 600 fattening steers. Watery and bloody diarrhea unresponsive to systemic broad-spectrum antibiotic therapy reveals a morbidity rate of approximately 15 %. The BCoV N gene was identified in 42.9 % (6/14) of the diarrheic fecal samples evaluated by semi-nested polymerase chain reaction (SN-PCR) technique. Other enteric microorganisms occasionally identified in adult cattle and evaluated in this study such as bovine groups A, B, and C rotavirus, bovine viral diarrhea virus, bovine torovirus, aichivirus B, and Eimeria sp. were not identified in the fecal samples. To the best knowledge of the authors, this is the first description of the BCoV diagnosis in fecal samples collected in a diarrhea outbreak in adult beef cattle grazing in the grass in a tropical country.

This study aimed to evaluate the natural infection by SaV in pigs of different categories of production cycle in an important Brazilian pig-producing region. Faecal samples (n = 169) of suckling, post-weaning, finisher and breeder pig categories were analysed. Animals were from five farrow-to-weaning and nine grower-to-finish commercial pig farms. The RT-PCR assay was performed targeting the partial RNA-dependent RNA polymerase (RdRp) gene of porcine SaV genome. The virus was detected in 23.7% (40/169) of faecal samples and in 10/14 (5/5 farrow-to-weaning; 5/9 grower-to-finish) of pig farms evaluated. Porcine SaV was most frequently (p < 0.05) detected in pigs at post-weaning than in grower-to-finish and breeder categories. The phylogenetic analysis revealed that the porcine SaV strains belong to the GIII and GIX? genogroups. This study showed that the porcine SaV GIII genogroup has spread in the pig herds and provides the first evidence of GIX? genogroup circulation in South America.

Listeriosis is a disease primarily of ruminants caused by the Gram-positive bacterium Listeria monocytogenes. Ruminants either demonstrate manifestations of the encephalitic, septicemic, or reproductive form of listeriosis. The pathological and molecular findings with encephalitic listeriosis in a 5.5-month-old, male, mixed-breed goat and a 3-year-old Texel-crossed sheep from northern Paraná, Brazil are described. Clinically, the kid demonstrated circling, lateral protrusion of the tongue, head tilt, and convulsions; the ewe presented ataxia, motor incoordination, and lateral decumbency. Brainstem dysfunctions were diagnosed clinically and listeriosis was suspected. Necropsy performed on both animals did not reveal remarkable gross lesions; significant histopathological alterations were restricted to the brainstem (medulla oblongata; rhombencephalitis) and were characterized as meningoencephalitis that consisted of extensive mononuclear perivascular cuffings, neutrophilic and macrophagic microabscesses, and neuroparenchymal necrosis. PCR assay and direct sequencing, using genomic bacterial DNA derived from the brainstem of both animals, amplified the desired 174 base pairs length amplicon of the listeriolysin O gene of L. monocytogenes. Phylogenetic analyses demonstrated that the strains associated with rhombencephalitis during this study clustered with known strains of L. monocytogenes lineage I from diverse geographical locations and from cattle of the state of Paraná with encephalitic listeriosis. Consequently, these strains should be classified as L. monocytogenes lineage I. These results confirm the active participation of lineage I strains of L. monocytogenes in the etiopathogenesis of the brainstem dysfunctions observed during this study, probably represent the first characterization of small ruminant listeriosis by molecular techniques in Latin America, and suggest that ruminants within the state of Paraná were infected by the strains of the same lineage of L. monocytogenes.

The aim of this study was to evaluate the frequency of Aichivirus C infection in the three major industrial pig-producing regions of Brazil. This retrospective study evaluated 63 faecal samples that were collected between 2004 and 2011 from suckling piglets (1 to 3 weeks old) belonging to 46 pig herds located in the South, Southeast and Central-west regions of Brazil. The presence of Aichivirus C in the samples was evaluated by reverse transcription-polymerase chain reaction assay. A 216-bp fragment of the aichivirus RNA-dependent RNA polymerase gene was amplified from 48 out of 63 (76.2 %) faecal samples. Aichivirus C was identified in all the evaluated regions, and variations in the frequency of virus detection among the different Brazilian regions were observed. Aichivirus C was detected at significantly higher rates in 2-week-old (18/20; 90.0 %) and 3-week-old (19/22; 86.4 %) piglets than in 1-week-old piglets (11/21; 52.4 %) (P < 0.05). The nucleotide sequences of three amplicons clustered together with other sequences previously isolated in Brazil, revealing that there were no phylogenetic differences in the strains of Aichivirus C by region or age. This study demonstrated that Aichivirus C has been present in Brazilian pig herds for years and has spread to the major pig-producing regions of the country.

Torque teno sus virus (TTSuV) is responsible for the infection of pig herds around the world. The aim of this study was to analyse the presence of natural infection by both species of TTSuV in suckling piglets from major pig-producing regions of Brazil. Faecal samples (n = 135) from 1 to 3-week-old suckling piglets from the Southern, Southeast and Midwest regions of Brazil were analysed by PCR assay to detect TTSuV1 and 2. TTSuV1 and 2 DNA was identified in 65 (48.1 %) and 23 (17 %) of piglet faecal samples, respectively. Co-infection by both species of TTSuV was detected in 17 (12.6 %) samples. Detection of TTSuV1 was significantly higher than that of TTSuV2 in the three Brazilian regions together (p < 0.05). Based on age of animals, TTSuV1 infection was statistically higher than TTSuV2 in each age group (p < 0.05). For all of the age groups together, no statistical difference was detected in the number of TTSuV1 and 2 positive results (p > 0.05). These findings revealed that TTSuV infection has disseminated in pig herds from different geographic Brazilian regions, and the presence of TTSuV in suckling piglet faecal samples suggested the early infection by the virus and the potential of these animals in spreading the virus.

Bovine coronavirus (BCoV) is one of the main causes of neonatal calf diarrhoea. Several diagnostic assays have been employed to detect the presence of the virus in stool samples from calves. Despite this, the frequency of BCoV infection among Brazilian and even South American cattle herds has yet to be well characterised. This study describes the occurrence of BCoV infection among calves from dairy and beef herds in four Brazilian states. A total of 282 stool samples from 1 to 60-day-old calves were evaluated for the presence of BCoV by a semi-nested (SN) PCR assay. The animals were from herds (n = 23) located in three geographical regions in Brazil (south, southeast, and center-west). The specific BCoV amplicon was detected in 15.6% (44/282) of the faecal specimens examined, of which 95.4% (42/44) were from diarrhoeic and 4.6% (2/44) from asymptomatic calves. The specificity of the SN-PCR amplicons was evaluated by restriction fragment length polymorphism (RFLP) analysis. The results show that the BCoV is widespread, mainly among calves from 16 to 30-days-old (p = 0.0023), and verify the association between BCoV infection and clinical signs of diarrhoea (p = 0.005). These findings emphasise the importance of this virus in enteric infections of Brazilian cattle herds.