A molecular survey using a validated real-time PCR assay finds no evidence of bovine alphaherpesvirus 2 in samples from animals with suspected vesicular disease in Brazil between 2014 and 2017.

Bovine alphaherpesvirus 2 (BoHV-2) is the etiologic agent of bovine mammillitis (BM) and pseudo-lumpy skin disease. BM is also important because its clinical presentation can be confused with foot-and-mouth disease (FMD), making it necessary to establish differential diagnoses and perform additional laboratory tests. The objective of this work was to use a validated real-time PCR assay to test for the presence of BoHV-2 in samples from cattle and buffalo with suspected vesicular disease in Brazil. The method could detect the virus at a concentration of 0.5 fg/µL and had 99.4% amplification efficiency, a repeatability error of only 4.1%, and good reproducibility with other reagents. No evidence of BoHV-2 causing vesicular disease in cattle and buffalo was found in this work. This study was able to validate a new methodology for detection of BoHV-2 and evaluate its usefulness for investigating outbreaks of vesicular disease Brazil. The importance of BoHV-2 in cases involving other clinical signs should still be studied using the qPCR developed in this work.

A common vaginal microbiota composition among breeds of Bos taurus indicus (Gyr and Nellore).

Describing the bovine vaginal microbiota is essential to better understand its physiology and its impact on health maintenance. Despite the economic importance of reproduction of these animals, bovine vaginal microbial community is still poorly described in comparison with rumen microbiome. Previous studies of our group described the vaginal microbiota of Nellore, an important Bos taurus indicus breed, using metagenomics. In order to better understand this microbiota, the present work aims to investigate another important breed, Gyr. Results have shown bacterial dominance over Archaea and Fungi was observed, with the most abundant bacterial phylum (Firmicutes) representing 40-50% of bacterial population, followed by Bacteroidetes, Proteobacteria, and Actinobacteria. The Fungi kingdom had the Mycosphaerella genus as its main representative, followed by Cladosporium. Archaea were observed at a very low abundance in all animals, with a high relative abundance of Methanobrevibacter genus. These results demonstrate a high microbial diversity on vaginal tract of Gyr, as demonstrated for Nellore and different from the previously described for other species. Our results indicate a great similarity between vaginal microbiota of Nellore and Gyr despite the differences in animal handling and genetic improvement. As observed for both breeds, individual variation is the largest source of microbial diversity between animals.

Role of the suppressor of cytokine signaling 2 (SOCS2) during meningoencephalitis caused by Bovine herpesvirus 5 (BoHV-5).

The role of suppressors of cytokine signaling (SOCS) in meningoencephalitis caused by Bovine herpesvirus 5 (BoHV-5) was evaluated by intracranial infection in C57BL/6 wild-type mice (WT) and SOCS2 deficient mice (SOCS2(-/-)). Both infected groups presented weight loss, ruffled fur and hunched posture. Additionally, infected SOCS2(-/-) mice showed swollen chamfer and progressive depression. Infected WT animals developed mild meningitis, characterized by infiltration of mononuclear cells. Moreover, viral DNA was detected in liver and lung from infected WT group. This group also showed elevated brain levels of IFN-γ, IL-10, CXCL1 and CCL5, when compared with non-infected WT animals. Brain inflammation was exacerbated in infected SOCS2(-/-) mice with widespread distribution of the virus and increased brain levels of TNF-α, IFN-γ, IL-10, IL-12, CXCL1 and CCL5, when compared with WT infected mice. Moreover, infected SOCS2 deficient mice exhibited reduced brain mRNA expression of IFNα and IFNß and increased expression of mRNA of SOCS1, compared with infected WT mice. Taken together, our study provides an insight into the role of SOCS2 in modulating the immune response to BoHV-5 infection.

Detection of multiple viral infections in cattle and buffalo with suspected vesicular disease in Brazil.

Vesicular diseases are of high importance for livestock, primarily because of foot-and-mouth disease (FMD), which is a high-morbidity disease that generates direct losses caused by low milk production, weight loss, and indirect losses because of the need for sanitary barriers. Other vesicular diseases are also of importance for livestock because of direct impacts or because their clinical signs may be confused with those of FMD. We report herein the detection of multiple infections in cattle with suspected vesicular disease in the Brazilian states of Amazonas (AM), Mato Grosso (MT), and Roraima. Thirty-seven epithelial samples from cattle and 1 sample from a buffalo were sent to the laboratory for testing for FMDV and similar disease agents. All samples from MT were positive for parapoxvirus (Pseudocowpox virus and Bovine papular stomatitis virus). In addition, 3 samples were positive for Bluetongue virus, and 5 samples were positive for Bovine herpesvirus 1 Among these samples, 1 was positive for all of these 3 agents. Only 2 samples from AM were negative for parapoxvirus. The molecular tests conducted in this study detected multiple infections, with a high prevalence of parapoxvirus.

Vaginal Microbiome Characterization of Nellore Cattle Using Metagenomic Analysis.

Understanding of microbial communities inhabiting cattle vaginal tract may lead to a better comprehension of bovine physiology and reproductive health being of great economic interest. Up to date, studies involving cattle microbiota are focused on the gastrointestinal tract, and little is known about the vaginal microbiota. This study aimed to investigate the vaginal microbiome in Nellore cattle, heifers and cows, pregnant and non-pregnant, using a culture independent approach. The main bacterial phyla found were Firmicutes (~40-50%), Bacteroidetes (~15-25%) and Proteobacteria (~5-25%), in addition to ~10-20% of non-classified bacteria. 45-55% of the samples were represented by only ten OTUs: Aeribacillus, Bacteroides, Clostridium, Ruminococcus, Rikenella, Alistipes, Bacillus, Eubacterium, Prevotella and non-classified bacteria. Interestingly, microbiota from all 20 animals could be grouped according to the respiratory metabolism of the main OTUs found, creating three groups of vaginal microbiota in cattle. Archaeal samples were dominated by the Methanobrevibacter genus (Euryarchaeota, ~55-70%). Ascomycota was the main fungal phylum (~80-95%) and Mycosphaerella the most abundant genus (~70-85%). Hormonal influence was not clear, but a tendency for the reduction of bacterial and increase of archaeal populations in pregnant animals was observed. Eukaryotes did not vary significantly between pregnant and non-pregnant animals, but tended to be more abundant on cows than on heifers. The present work describes a great microbial variability in the vaginal community among the evaluated animals and groups (heifers and cows, pregnant and non-pregnant), which is significantly different from the findings previously reported using culture dependent methods, pointing out the need for further studies on this issue. The microbiome found also indicates that the vaginal colonization appears to be influenced by the gastrointestinal community.

Bovine herpesvirus 6 in buffaloes (Bubalus bulalis) from the Amazon region, Brazil.

This study presents the first description of Bovine herpesvirus 6 (BoHV-6) that was isolated from buffaloes of Amazon region in Brazil. Phylogenetic analysis showed that the BoHV-6 Brazilian strains clustered with the sequence of BoHV-6 from elsewhere available at the GenBank. It was observed in some buffaloes with lymphoproliferative disease in one herd, thus the animals were also tested for Bovine leukemia virus (BLV), which has been associated to lymphoma in bovines. All animals were negative to BLV. These results indicate that BoHV-6 is present in buffaloes in Brazil, but the importance and impact of this infection and its association with any illness is still undefined.

Immune response of calves inoculated with proteins of Anaplasma marginale bound to an immunostimulant complex.

Despite our current knowledge of the immunology, pathology, and genetics of Anaplasma marginale, prevention in cattle is currently based on old standbys, including live attenuated vaccines, antibiotic treatment, and maintaining enzootic stability in cattle herds. In the present study, we evaluated the use of an immunostimulant complex (ISCOMATRIX) adjuvant, associated with a pool of recombinant major surface proteins (rMSP1a, rMSP1b, rMSP4 and rMSP5) to improve the humoral immune response triggered in calves mainly by IgG2. Ten calves were divided in three groups: 4 calves were inoculated with the ISCOMATRIX/rMSPs (G1); 2 calves were inoculated with ISCOMATRIX adjuvant (G2); and 4 calves received saline (G3). Three inoculations were administered at 21-day intervals. In G1, the calves showed significant increases in total IgG, IgG1 and IgG2 levels 21 days after the second inoculation, compared to the control group (p < 0.05), and G1 calves remained above the cut-off value 28 days after the third inoculation (p < 0.05). The post-immunized sera from calves in G1 reacted specifically for each of the rMSPs used. In conclusion, the ISCOMATRIX/rMSPs induced antigen-specific seroconversion in calves. Therefore, additional testing to explore the protection induced by rMSPs, both alone and in conjunction with proteins previously identified as subdominant epitopes, is warranted.

Immune response of calves inoculated with proteins of Anaplasma marginale bound to an immunostimulant complex / Resposta imune de bezerros inoculados com proteínas de Anaplasma marginale ligadas a um complexo imunoestimulante

Despite our current knowledge of the immunology, pathology, and genetics of Anaplasma marginale, prevention in cattle is currently based on old standbys, including live attenuated vaccines, antibiotic treatment, and maintaining enzootic stability in cattle herds. In the present study, we evaluated the use of an immunostimulant complex (ISCOMATRIX) adjuvant, associated with a pool of recombinant major surface proteins (rMSP1a, rMSP1b, rMSP4 and rMSP5) to improve the humoral immune response triggered in calves mainly by IgG2. Ten calves were divided in three groups: 4 calves were inoculated with the ISCOMATRIX/rMSPs (G1); 2 calves were inoculated with ISCOMATRIX adjuvant (G2); and 4 calves received saline (G3). Three inoculations were administered at 21-day intervals. In G1, the calves showed significant increases in total IgG, IgG1 and IgG2 levels 21 days after the second inoculation, compared to the control group (p < 0.05), and G1 calves remained above the cut-off value 28 days after the third inoculation (p < 0.05). The post-immunized sera from calves in G1 reacted specifically for each of the rMSPs used. In conclusion, the ISCOMATRIX/rMSPs induced antigen-specific seroconversion in calves. Therefore, additional testing to explore the protection induced by rMSPs, both alone and in conjunction with proteins previously identified as subdominant epitopes, is warranted.

Apesar dos avanços da imunologia, patologia e genética de Anaplasma marginale, a prevenção em bovinos ainda é baseada nas vacinas vivas atenuadas, na terapia com antibiótico e estabilidade enzoótica dos rebanhos bovinos. No presente estudo, avaliou-se o uso de um complexo imunoestimulante (ISCOMATRIX), associado às proteínas recombinantes de superfície (rMSP1a, rMSP1b, rMSP4 e rMSP5) para melhorar a resposta imune humoral desencadeada em bezerros, principalmente por IgG2. Dez animais foram divididos em três grupos: 4 bezerros foram inoculados com o ISCOMATRIX/rMSPs (G1), 2 bezerros foram inoculados com ISCOMATRIX adjuvante (G2) e 4 bezerros receberam salina (G3). Três doses vacinais foram administradas em intervalos de 21 dias. No G1, os bezerros apresentaram aumentos significativos nos níveis de IgG total, IgG1 e IgG2 21 dias após a segunda inoculação, em comparação com o grupo de controle (p <0,05). Nos bezerros do G1 esses níveis de anticorpos permaneceram acima do ponto de corte 28 dias após a terceira inoculação (p < 0,05). Os soros pós-imunização de bezerros do G1 reagiram especificamente com cada uma das rMSPs utilizadas. Em conclusão, o ISCOMATRIX/rMSPs induziu soroconversão antígeno-específica em bezerros. Portanto, se justifica a realização de ensaios adicionais para explorar a proteção induzida pela rMSPs, tanto sozinhas como em conjunto com novas proteínas identificadas com epítopos subdominantes.

Induced immune response of Escherichia coli BL21 expressing recombinant MSP1a and MSP1b proteins of Anaplasma marginale

This work aims to evaluate the potential of immunization with E. coli BL21 expressing the recombinant rMSP1a and rMSP1b proteins of Anaplasma marginale. E. coli BL21 was transformed with recombinant plasmids pET102/msp1α and pET101/msp1β, and rMSP1a and rMSP1b were expressed after induction by IPTG. BALB/c mice were vaccinated with formolized BL21/rMSP1a and BL21/rMSP1b, and the production in mice sera of whole IgG was determined by ELISA. The mice immunized with BL21/rMSP1a showed a better humoral response for whole IgG when compared to the mice immunized with BL21/rMSP1b; these mice exhibited a small response after the second vaccination. Sera of mice immunized with BL21/rMSP1a reacted via western blot with BL21 and rMSP1a, with molecular masses varying from 70 to 105 kDa. Sera of mice immunized with BL21/rMSP1b reacted with BL21 and rMSP1b with a molecular mass of 100 kDa. These results demonstrate that BL21 containing rMSP1a and rMSP1b in the outer membrane were able to produce an immune response in mice, reinforcing its use in vaccine models against bovine anaplasmosis.

Esse trabalho avaliou o potencial de imunização de Escherichia coli BL21 expressando as proteínas recombinantes rMSP1a e rMSP1b de Anaplasma marginale. A E. coli BL21 foi transformada com os plasmídios recombinantes pET102/msp1α e pET101/msp1β e as proteínas rMSP1a e rMSP1b foram expressas após indução com IPTG. Camundongos BALB/c foram vacinados com BL21/rMSP1a e BL21/rMSP1b formolisadas, e a produção de IgG total foi determinada pelo teste de ELISA nos soros dos camundongos imunizados. Os camundongos imunizados com a BL21/rMSP1a mostraram uma melhor resposta humoral para IgG total, comparada à resposta apresentada pelos camundongos imunizados com BL21/rMSP1b; estes camundongos exibiram uma menor resposta após a segunda vacinação. Soros de camundongos imunizados BL21/rMSP1a reagiram pelo western blot com BL21 e rMSP1a, com massa molecular variando de 70 a 105 kDa. Soro de camundongos imunizados com BL21/rMSP1b reagiram com BL21 e rMSP1b com massa molecular de 100 kDa. Esses resultados demonstram que BL21 contendo rMSP1a e rMSP1b na membrana externa foram capazes de produzir resposta imune em camundongos, reforçando o seu uso em modelos de vacina contra a anaplasmose bovina.