In the present study, a nested-PCR system, targeting the TbD1 region, involving the performance of conventional PCR followed by real-time PCR, was developed to detect Mycobacterium bovis in bovine/bubaline tissue homogenates. The sensitivity and specificity of the reactions were assessed with DNA samples extracted from tuberculous and non-tuberculous mycobacteria, as well as other actinomycetales species and DNA samples extracted directly from bovine and bubaline tissue homogenates. In terms of analytical sensitivity, the DNA of M. bovis AN5 was detected up to 1.56 ng with conventional PCR, 97.6 pg with real-time PCR, and 1.53 pg with nested-PCR in the reaction mixture. The nested-PCR exhibited 100% analytical specificity for M. bovis when tested with the DNA of reference strains of environmental mycobacteria and closely-related Actinomycetales. A clinical sensitivity value of 76.0% was detected with tissue samples from animals that exhibited positive results in the comparative intradermal tuberculin test (CITT), as well as from those with lesions compatible with tuberculosis (LCT) that rendered positive cultures. A clinical specificity value of 100% was detected with tissue samples from animals with CITT- results, with no visible lesions (NVL) and negative cultures. No significant differences were found between the nested-PCR and culture in terms of detecting CITT+ animals with LCT or with NVL. No significant differences were recorded in the detection of CITT- animals with NVL. However, nested-PCR detected a significantly higher number of positive animals than the culture in the group of animals exhibiting LCT with no previous records of CITT. The use of the nested-PCR assay to detect M. bovis in tissue homogenates provided a rapid diagnosis of bovine and bubaline tuberculosis.

Although a complete characterization of the immune response elicited by rChi/adjuvant in hamsters is required, it is believed that the construction of chimeric genes is an important attempt towards the generation of an effective vaccine against leptospirosis.

The aim of this study was to investigate the occurrence of Hepatozoon species infecting dogs in the municipality of Campo Grande, Mato Grosso do Sul (MS), Brazil, using blood samples (n = 165) drawn from dogs. The species Hepatozoon canis was identified in 3.63% of the tested animals using molecular tools. Further studies are needed to determine the clinical relevance of this infection and the main arthropod vectors involved in its transmission.Keywords: Dogs, epidemiology, Hepatozoon canis, midwestern Brazil, PCR. ResumoO objetivo deste estudo foi identificar a frequência e espécies de Hepatozoon infectando cães no município de Campo Grande, Mato Grosso do Sul, Brasil. Uma amostragem de 165 animais foi utilizada e, por meio do uso de ferramentas moleculares, a espécie Hepatozoon canis foi identificada em 3,63% dos animais. Mais estudos são necessários para identificar a relevância clínica e os principais vetores envolvidos na transmissão desse protozoário na região.Palavras-chave: Cães, epidemiologia, Hepatozoon canis, centro-oeste do Brasil, PCR.

Leptospirosis is a zoonotic disease caused by Leptospira and domestic dogs can act as host of some serovars. In order to analyze the transmission dynamics in a dog population, with and without immunization, a longitudinal study was carried out with a focus to evaluate antibody response and to identify serovars. Blood samples were collected in three consecutive years (2015 to 2017) from 331, 373 and 347 dogs respectively. The dog seroprevalence in each year was 11%, 7% and 14%, respectively, and the incidence in 2016 was 5% and in 2017, 14%. The most frequent serovars were Cynopteri and Butembo in 2015, Cynopteri, Butembo and Hardjoprajitno in 2016, and Canicola and Butembo in 2017. Dogs can play a role as sentinel animals and hosts of Leptospira serovars. The percentage of seropositive dogs due to vaccination was higher than the previous years without immunization and lower than in previous years for other serovars, which we interpret as evidence for the importance of immunization. These parameters associated with active canine population control are important for prevention and control of leptospirosis not only in dogs but alsoto inhibit the transmission between dogs and humans.

Objectives The present study assessed the sensitivity and biosafety of the FTA Elute Card® (FTA) (GE Healthcare) as an alternative preservation method of gross lesions for bovine tuberculosis diagnosis, that can endure large distances and high environmental temperatures, which are found in the Brazilian territory. Results The FTA card was compared to the freezing and sodium borate solution methods to preserve 134 gross lesions samples from slaughterhouses located in three Brazilian states. The calculated value for the sensitivity of sodium borate solution (SBS) stored for 30 days was higher than those estimated for the methods of freezing and SBS stored for 60 days, when the PCR and isolation results were interpreted in parallel (0.55). The FTA cards presented the lowest diagnostic sensitivity and did not inactivate all mycobacteria. Given the rush of a slaughterhouse routine, the quantity of lesions with different pathological stages cannot be measured on each FTA card. Thus, as a preservation method of gross tuberculosis lesions, the FTA cards can present infection risks for people who have direct or indirect contact with them.