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SUMMARY: This study aims to characterize the environmental microbiota of an egg-producing farm situated in Rio Grande do Sul, Southern Brazil, spanning from the chick to the laying hen stages and encompassing the treatment of carcasses and manure. Metataxonomy analyses reveal the continuity of bacterial diversity across the production stages (chick, pullet, and laying hen). The presence of Fusobacteriota and Cyanobacteria in poultry environments before any manure or carcass treatments (named pre-treatment samples) are identified as indicative phyla markers for healthy animals. Nonetheless, alterations in the bacterial communities emerge during the treatment of manure and carcasses (treatment samples), revealing an increased abundance of Halanaerobiaeota. In summary, the study underscores the key phyla influencing the entire environment of the egg production process on a farm in South Brazil. Although our data is from a specific farm, it provides insights for a more robust and representative study of the egg chain.

Abstract The purpose of this study was to compare the composition and stability of bacteria and fungi communities during the propagation of sourdoughs prepared with organic or conventional whole wheat (Triticum aestivum) flours from South Brazil. Sourdoughs were prepared and samples were collected during different fermentation times (0 to 216 h). Total DNA of sourdough samples were extracted and the 16S rRNA gene and Internal Transcribed Spacer region were sequenced by MiSeq-Illumina. A total of 43 and 56 OTUs were identified and defined as core taxa in the bacterial and fungal communities, respectively. The analysis revealed increases in the relative abundances of the lactic acid (Pediococcus pentosaceus, Weissella hellenica and Limosilactobacillus pontis) and acetic acid bacteria (Gluconobacter frateurii and Acetobacter tropicalis) during the sourdough propagation. The filaments fungi, Alternaria tenuissima, Fusarium culmorum, Fusarium petersiae and Microdochium seminicola remained more stable in organic than conventional during propagation cycles. After 216 h of fermentation, both sourdoughs were dominated by acid- and salt-tolerant yeast Issatchenkia orientalis (syn Pichia kudriavzevii, and Candida glycerinogenes). In conclusion, there were no significant differences in microbial communities among the sourdough samples. This study revealed that both flours contain autochthonous LAB, AAB, and yeasts with biotechnological applications in sourdough bread-making.

Abstract Zika virus (ZIKV) infection during pregnancy was associated with microcephaly in neonates, but clinical and experimental evidence indicate that ZIKV also causes neurological complications in adults. However, the changes in neuron-glial communication, which is essential for brain homeostasis, are still unknown. Here, we report that hippocampal slices from adult rats exposed acutely to ZIKV showed significant cellular alterations regarding to redox homeostasis, inflammatory process, neurotrophic functions and molecular signalling pathways associated with neurons and glial cells. Our findings support the hypothesis that ZIKV is highly neurotropic and its infection readily induces an inflammatory response, characterized by an increased expression and/or release of pro-inflammatory cytokines. We also observed changes in neural parameters, such as adenosine receptor A2a expression, as well as in the release of brain-derived neurotrophic factor and neuron-specific enolase, indicating plasticity synaptic impairment/neuronal damage. In addition, ZIKV induced a glial commitment, with alterations in specific and functional parameters such as aquaporin 4 expression, S100B secretion and glutathione synthesis. ZIKV also induced p21 senescence-associated gene expression, indicating that ZIKV may induce early senescence. Taken together, our results indicate that ZIKV-induced neuroinflammation, involving nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor κB (NFκB) pathways, affects important aspects of neuron-glia communication. Therefore, although ZIKV infection is transient, long-term consequences might be associated with neurological and/or neurodegenerative diseases.

Summary: Background: Gut microbiota-derived short-chain fatty-acid (SFCA) acetate protects mice against RSV A2 strain infection by increasing interferon-β production and expression of interferon-stimulated genes (ISGs). However, the role of SFCA in RSV infection using strains isolated from patients is unknown. Methods: We first used RSV clinical strains isolated from infants hospitalized with RSV bronchiolitis to investigate the effects of in vitro SCFA-acetate treatment of human pulmonary epithelial cells. We next examined whether SCFA-acetate treatment is beneficial in a mouse model of RSV infection using clinical isolates. We sought to investigate the relationship of gut microbiota and fecal acetate with disease severity among infants hospitalized with RSV bronchiolitis, and whether treating their respiratory epithelial cells with SCFA-acetate ex-vivo impacts viral load and ISG expression. We further treated epithelial cells from SARS-CoV-2 infected patients with SCFA-acetate. Findings: In vitro pre-treatment of A549 cells with SCFA-acetate reduced RSV infection with clinical isolates and increased the expression of RIG-I and ISG15. Animals treated with SCFA-acetate intranasally recovered significantly faster, with reduction in the RSV clinical isolates viral load, and increased lung expression of IFNB1 and the RIG-I. Experiments in RIG-I knockout A549 cells demonstrated that the protection relies on RIG-I presence. Gut microbial profile was associated with bronchiolitis severity and with acetate in stool. Increased SCFA-acetate levels were associated with increasing oxygen saturation at admission, and shorter duration of fever. Ex-vivo treatment of patients’ respiratory cells with SCFA-acetate reduced RSV load and increased expression of ISGs OAS1 and ISG15, and virus recognition receptors MAVS and RIG-I, but not IFNB1. These SCFA-acetate effects were not found on cells from SARS-CoV-2 infected patients. Interpretation: SCFA-acetate reduces the severity of RSV infection and RSV viral load through modulation of RIG-I expression. Funding: FAPERGS (FAPERGS/MS/CNPq/SESRS no. 03/2017 - PPSUS 17/2551-0001380-8 and COVID-19 20/2551-0000258-6); CNPq 312504/2017-9; CAPES) - Finance Code 001.

The serum neutralization (SN) test is the gold standard method to measure neutralizing antibodies to bovine herpesviruses. However, in view of the further subdivisions of bovine herpesviruses in types/subtypes, defining which virus to use at challenge in SN tests may be difficult. In view of that, this study was carried out to re-evaluate (SN) sensitivity with different types/subtypes of bovine herpesviruses types 1 (BoHV-1) and 5 (BoHV-5) as challenge viruses. Bovine sera (n=810) were collected from two distinct geographic regions and tested by SN with three type 1 viruses (BoHV-1.1 strains "Los Angeles" and "EVI123/98"; BoHV-1.2a strain "SV265/96") and three type 5 viruses (BoHV-5a strain "EVI88/95"; BoHV-5b strain "A663" and BoHV-5c "ISO97/95"). SN tests were performed with a 1 hour incubation of the serum-virus mixtures at 37ºC against 100 TCID50 of each of the viruses. SN sensitivity varied greatly depending on the challenge virus used in the test. The highest sensitivity (327 positive/810 total sera tested; 40.37%) was attained when the positive results to the six viruses were added together. No association could be found between any particular type or subtype of virus and the sensitivity of the test. When positive results to each single strain were considered, SN sensitivity varied from 41.7% to 81.7%, depending on the virus and the geographic region of origin of the sera. Variation was detected even when challenge viruses belonged to the same subtype, where disagreement between positive results reached 41%. These results indicate that one hour incubation SN tests against single viruses, as performed here, may display a significantly low sensitivity (p=0.05); performing SN tests against a number of different viruses may increase considerably SN sensitivity. Furthermore, the choice of virus used for challenge is critical in SN tests. In addition, sera from different geographic regions may give rise to disagreeing results with different strains of BoHV-1 and BoHV-5. This might be particularly relevant for control programs and in international trade, were maximum sensitivity should be targeted.O teste de soroneutralização (SN) é o método padrão para a mensuração de anticorpos neutralizantes para herpesvírus bovinos. Entretanto, com as subdivisões propostas destes agentes em tipos e subtipos, a definição de qual amostra utilizar como virus de desafio à SN pode ser difícil. Em vista disso, este estudo foi realizado para re-avaliar a sensibilidade de testes de SN utilizando diferentes tipos e subtipos de herpesvírus bovinos tipos 1 (BoHV-1) e 5 (BoHV-5) como amostras de desafio. Soros bovinos (n=810) foram coletados de duas regiões geográficas distintas e testados frente a amostras do tipo 1 (BoHV-1.1: amostras "Los Angeles" e "EVI123/98", BoHV-1.2a: amostra "SV265/96") e três amostras do tipo 5 (BoHV-5a: "EVI88/95"; BoHV-5b: "A663" e BoHV-5c "ISO97/95"). Os testes de SN foram realizados com incubação de 1 hora a 37ºC da mistura soro-vírus, frente a 100 doses infectantes para 50% dos cultivos celulares (DICC50) de cada um dos vírus. A sensibilidade da SN variou grandemente em função do vírus utilizado no teste. A maior sensibilidade (327 soros positivos/810 soros testados; 40.37%) foi alcançada quando os resultados positivos frente aos seis diferentes vírus foram somados. Nenhuma associação foi detectada entre determinado tipo/subtipo de vírus e a sensibilidade do teste. Quando resultados positivos frente a cada vírus foram considerados isoladamente, a sensibilidade da SN variou entre 41,7% a 81,7%, dependendo do vírus de desafio e da região geográfica de origem das amostras de soro. Variação foi detectada mesmo quando as amostras de desafio pertenciam a um mesmo subtipo; a discrepância entre os resultados positivos atingiu até 41%. Estes resultados indicam que testes de SN contra amostras isoladas de vírus podem apresentar uma sensibilidade notadamente baixa; o emprego de diferentes amostras de vírus de desafio pode aumentar consideravelmente a sensibilidade da prova. Além disso, a escolha da amostra de vírus para a realização do teste é crítica. Outro achado importante é que sorors de diferentes regiões geográficas podem dar resultados discordantes frente a diferentes amostras de BoHV-1 e BoHV-5. Estes achados são particularmente relevantes para programas de controle destas infecções e para o comércio internacional, onde a sensibilidade deve ser maximizada.

Este estudo objetivou estimar a prevalência de anticorpos contra os herpesvírus bovinos tipos 1 e 5 (BoHV-1 e BoHV-5) no Estado do Rio Grande do Sul (RS), Brasil, frente a diferentes cepas de BoHV-1 e BoHV-5. As amostras de soro utilizadas foram extraídas de uma amostragem mais ampla, desenhada para estimar a prevalência de brucelose bovina no Estado. Todos os soros foram coletados de vacas com idade igual ou superior a 24 meses de idade, não vacinadas contra herpesvírus bovinos, de rebanhos de corte e leite. O cálculo amostral foi baseado em uma expectativa de prevalência média de infecção de 33%, considerando-se um erro padrão não superior a 1% e um intervalo de confiança de 95%. Com base nesse cálculo foram examinados 2.200 soros, provenientes de 390 propriedades e 158 municípios. Os soros foram analisados na busca de anticorpos contra BoHV-1 e BoHV-5 pela técnica de soroneutralização (SN), executada frente a quatro cepas de vírus distintas: EVI123/98 e Los Angeles (BoHV-1.1); EVI88/95 (BoHV-5a) e A663 (BoHV-5b). A prevalência média de anticorpos contra o BoHV-1 e BoHV-5 nos animais amostrados foi de 29,2% (642/2200); animais soropositivos foram identificados em 57,7% (225/390) dos rebanhos. As estimativas de prevalência variaram de acordo com a cepa e/ou vírus utilizado para o desafio nos testes de SN. A prevalência e a sensibilidade mais altas foram obtidas quando os resultados positivos à SN frente aos quatro vírus distintos foram somados. O uso de somente um vírus de desafio na SN levaria a redução de sensibilidade de 20,4% a 34,6% quando comparada com os resultados positivos combinados. Estes achados evidenciam que anticorpos contra BoHV-1 e BoHV-5 estão amplamente difundidos nos rebanhos do RS, embora a prevalência em distintas regiões geográficas seja bastante variada. Os resultados obtidos nas estimativas de prevalência foram fortemente afetados pelas diferentes amostras de vírus usadas nos testes de SN. Esse fato deve ser levado em consideração quando estudos sorológicos para BoHV-1 e BoHV-5 forem realizados. Como a SN não é capaz de discriminar as respostas de anticorpos para BoHV-1 e BoHV-5, a prevalência tipo-específica permanece desconhecida.This study was carried out to estimate the prevalence of antibodies to bovine herpesviruses types 1(BoHV-1) and 5 (BoHV-5) in the state of Rio Grande do Sul (RS), Brazil, by testing serum samples against different BoHV-1 and BoHV-5 strains. The sera examined were obtained from a larger sample designed to estimate the prevalence of bovine brucellosis within the state. All sera were collected from cows 24 months or older, not vaccinated to bovine herpesviruses, from both dairy and beef herds. The number of samples to be tested was calculated based on an estimated prevalence of infection of 33%, with an average standard deviation of £1% and a 95% limit of agreement. Sera from 2.200 cattle from 390 farms distributed in 158 counties were tested by serum neutralization (SN) tests in search for antibodies to the following strains: BoHV-1.1 (strains EVI123/98 and Los Angeles), BoHV-5a (strain EVI88/95) and BoHV-5b (strain A663). The overall seroprevalence to BoHV-1 and BoHV-5 in the sampled herds was 29.2% (642/2.200); seropositive animals were detected in 225 (57.7%) of the sampled farms. Prevalence estimates varied according to the virus used for challenge in SN tests. The highest prevalence and sensitivity were attained when positive SN results against the four different strains were added together. The use of only one virus for challenge in SN tests would lead to a loss in sensitivity from 20.4% to 34.6% when compared to the combined SN-positive results. These findings provide evidence that antibodies to BoHV-1 and BoHV-5 are largely spread in dairy and beef herds in RS, although prevalence in distinct geographic regions is quite variable. The results were strongly affected by the virus strains used for challenge in SN testing. This must be taken into account when performing serologic tests to detect BoHV-1 and BoHV-5 antibodies. As SN test is not capable of discriminating between antibody responses to BoHV-1 and BoHV-5, type-specific prevalence remains unknown.

The complete genome sequence of bovine papillomavirus 2 (BPV2) from Brazilian Amazon Region was determined using multiple-primed rolling circle amplification followed by Illumina sequencing. The genome is 7,947 bp long, with 45.9% GC content. It encodes seven early (E1, E2,E4, E5, E6,E7, and E8) and two late (L1 and L2) genes. The complete genome of a BPV2 can help in future studies since this BPV type is highly reported worldwide although the lack of complete genome sequences available.