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Erysipelothrix sp. isolates obtained from a deadly outbreak in farmed turkeys were sequenced and compared to representatives of the genus. Phylogenetic trees—supported by digital DNA:DNA hybridization and Average Nucleotide Identity—revealed a novel monophyletic clade comprising isolates from pigs, turkeys, and fish, including isolates previously described as E. sp. Strain 2. Genes coding for the SpaC protein, typically found in E. sp. Strain 2, were detected in all isolates of the clade. Therefore, we confirm E. sp. Strain 2 represents a unique species that may be isolated from a broad host range, and the name “Erysipelothrix takahashiae” is suggested. Core genome analysis showed that the pathogenic species of this genus, E. rhusiopathiae and the clade E. sp. Strain 2, are enriched in core functionalities related to nutrient uptake and transport, but not necessarily homologous pathways. For instance, whereas the aerobic DctA transporter may uptake C4-dicarboxylates in both species, the anaerobic DcuC transporter is exclusive of the E. sp. Strain 2. Remarkably, the pan-genome analysis uncovered that genes related to transport and metabolism, recombination and repair, translation and transcription in the fish isolate, within the novel clade, have undergone a genomic reduction through pseudogenization. This reflects distinct selective pressures shaping the genome of species and strains within the genus Erysipelothrix while adapting to their respective niches.

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An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Leptospirosis is a zoonotic disease of world importance, and its transmission depends on the interaction between humans and animals. Given the necessity to investigate potential hosts of Leptospira spp., this study verified the prevalence of different serovars in the species of Rhipidomys spp., a widespread sigmodont rodent in Brazil. The studied population originates from a semi-evergreen forest located in the county of Uberlândia, in the state of Minas Gerais. The microscopic agglutination test (MAT) was performed with 14 serovars. Thirteen out of the 43 wild rodents captured showed a positive agglutination reaction, with a greater prevalence of the serovars Pyrogenes, Copenhageni, and Canicola. This study found a prevalence of 30.3% anti-Leptospira spp. antibodies; all positive animals were reactive to more than one serovar.

A Leptospirose é uma doença cosmopolita de grande relevância para a Medicina Veterinária por ocorrer em diversas espécies domesticas e silvestres, podendo causar prejuízos nos setores produtivos e preocupações para a saúde pública. Assim, o objetivo do trabalho foi avaliar a frequência de bovinos, bubalinos, caninos selvagens, caninos, caprinos, equinos, felinos, ovinos, roedores e suínos sororeagentes ao teste para leptospirose e quais sorogrupos foram mais prevalentes. Para tal, foram compilados os resultados dos exames de leptospirose obtidos pelo teste de Soroaglutinação Microscópica realizados no Laboratório de Doenças Infectocontagiosas da Faculdade de Medicina Veterinária da Universidade Federal de Uberlândia, entre os anos de 2011 a 2014. A espécie que apresentou maiores índices de soropositividade foi a bovina, o sorogrupo mais prevalente foi o Sejroe.

Leptospirosis is a disease with worldwide distribution and with risk to human health. In addition, it affects farm animals, and consequently, causes economic losses to farmers. Therefore, understanding the epidemiological profile of the disease in each geographical region is essential. This study was conducted in the rural properties of the municipality of Ipameri, state of Goiás, Brazil, where leptospirosis has not been reported in dairy farming. The objective of this study was to determine the seroprevalence of leptospirosis in dairy cattle, identify the serovars present, and correlate these results with factors that could favor the appearance of the disease. For this purpose, 285 blood samples were collected from dairy cows and microscopic agglutination tests were conducted to identify the 15 serovars of Leptospira interrogans. A structured questionnaire was applied during the visits to the properties to assess the factors associated with leptospirosis. The prevalence was found to be 18.9%, and the serovars present in the region included Hardjo, Wolffi, Canicola, Hebdomadis, Australis, and Icterohaemorrhagiae. The variables associated with leptospirosis were the presence of reproductive changes in the herd, presence of rodents, increased daily production of milk, hired labor, and lower level of education of the producers. Key words: Leptospira. Reproduction. Microscopic agglutination test. Production systems. ResumoA leptospirose é uma doença de distribuição mundial, que oferece riscos à saúde humana e acomete os animais de produção, gerando perdas econômicas ao produtor rural, sendo importante conhecer o perfil epidemiológico da doença em cada região. Esse estudo foi realizado em propriedades rurais do município de Ipameri, estado de Goiás, onde não existia nenhum relato sobre a leptospirose na pecuária leiteira. O objetivo desta pesquisa foi determinar a soroprevalência de leptospirose nos bovinos leiteiros, os soravares presentes e correlacionar os resultados com variáveis que podem favorecer o aparecimento da doença. Para isso foram coletadas 285 amostras de sangue de vacas em lactação e realizado o teste diagnóstico de soroaglutinação microscópica em campo escuro (SAM) contra 15 sorovares de Leptospira interrogans. Aplicou-se um questionário estruturado durante a visita para avaliar os fatores associados à ocorrência da leptospirose. A prevalência encontrada foi de 18,9%, e os

Background: Leptospirosis is a zoonosis that affects many species of mammals and occurs endemically in Brazil. The biofilm matrix provides structure and protection to the biofilm cells working as a physical barrier to antibiotic agents, which are attached or consumed by the matrix components. However, this attribute varies according to the matrix, antimicrobial agent and biofilm age. Leptospira may change morphologically according to environmental conditions, including cell aggregation and biofilm formation. Leptospira can colonize the ducts of kidney from hosts for a long time, forming a biofilm, which is believed to be an important factor for their maintenance in animals and in the environment. Thus, the objective of this research was to determine the biofilm formation capacity of four strains of Leptospira interrogans.Materials, Methods & Results: The strains were typified by WHO/FAO/OIE and National Collaborating Center for Reference and Research on Leptospirosis (Kit Biomedical Research, Amsterdam, Netherlands). Leptospira interrogans strains, two isolated from cattle and two isolated from dogs were biofilms tested for adhesion on polystyrene plates, extracellular matrix composition and confocal microscopy. In the plating adhesion test, the suspension was inoculated into 96-well sterile polystyrene microplates with flat bottom at a ratio of 1:200 in EMJH medium, followed by 24 h incubation at 28°C, with medium renewal after 12 h. After this period the wells were washed three times with sterile PBS and following incubation; the plates were dried in the oven at 60°C for 30 min and added 200 μL of 1% violet crystal for five min. Subsequently, the plates were washed with distilled water, after complete removal, 200 μL of acetic acid 33% was added and the readings were performed at 570 nm in the ELISA reader. The proteins and polysaccharides were quantified in a scraped pooled sample diluted in 0.85% sterile saline solution to achieve an optimal amount for testing used reagents of the BCA kit. The polysaccharide content was determined by adding into a tube, an aliquot of 0.5 mL from the pooled sample, 0.5 mL of phenol and then immediately 2.5 mL of sulfuric acid. The solution was homogenized and left to react for 15 min at room temperature. The reading was performed at 490 nm in ELISA reader. The strains were compared regarding polysaccharides and protein matrices using analysis of variance (ANOVA) and Tukey test. At confocal microscopy the strains were incubated with the tested polypropylene material for 24 h. The materials were washed with sterile phosphate buffer and stained with propidium iodide. The reading was performed using a Laser Scanning Confocal Microscope (Zeiss 710) with laser excitation (488 nm) and 580-680 nm emission filters for propidium iodide (red marking). All strains displayed strong adherence on microplate and the amount of polysaccharides in biofilm was not statistically different among the studied strains, but the amount of protein was significantly different in strain 4 (P > 0.5). The confocal microscopy showed the adherence of the Leptospira spp. strains to polypropylene material after washing.Discussion: Biofilm production plays an important role in the maintenance of a chronic infection by Leptospira interrogans with renal colonization. The exopolysaccharide (EPS) has various functions, such as checking insolubility in water; giving the three-dimensional conformation of the biofilm; protecting cells from physical (mechanical action, irradiation and temperature variations), chemical.