A genetic and virulence characterization of Brazilian strains of Mycoplasma hyopneumoniae.

Mycoplasma hyopneumoniae (M. hyopneumoniae) is considered the primary causative agent of porcine enzootic pneumonia (EP), a chronic contagious respiratory disease that causes economic losses. Obtaining new pathogenic isolates and studying the genome and virulence factors are necessary. This study performed a complete sequencing analysis of two Brazilian strains, UFV01 and UFV02, aiming to characterize the isolates in terms of the virulence factors and sequence type. The complete genome analysis revealed the main virulence genes (mhp385, mhp271, MHP_RS03455, p102, p97, p216, MHP_RS00555, mhp107) and ST-123, the presence of three toxin-related genes (tlyC, PLDc_2 and hcnC), and some genetic groups specific to these two isolates. Subsequently, the pathogenicity of the isolates was evaluated via an experimental infection conducted in a swine model. The study was divided into three groups, namely a negative control group (n = 4) and two test groups (n = 8), totaling 20 animals. They were challenged at 35 days of age with 107 CCU (Color Changing Units) M. hyopneumoniae via the intratracheal route. The UFV01 group showed earlier and higher seroconversion (IgG) (100%), while only 50% of the UFV02 group seroconverted. The same trend was observed when analyzing the presence of IgA in the bronchoalveolar lavage fluid (BALF) at 35 days post-infection (dpi). The UFV01 group had a mean macroscopic lesion score of 11.75% at 35 dpi, while UFV02 had 3.125%. Microscopic lesions were more severe in the UFV01 group. Based on laryngeal swab samples evaluated by qPCR, and the detection began at 14 days. The UFV01 group showed 75% positivity at 14 dpi. The UFV02 group also started excreting at 14 dpi, with a positivity rate of 37.5%. The results indicate that the UFV01 isolate exhibits higher virulence than UFV02. These findings may aid in developing new vaccines and diagnostic kits and establishing experimental models for testing.

Serosurvey of antibodies against zoonotic pathogens in free-ranging wild canids (Cerdocyon thous and Lycalopex gymnocercus) from Southern Brazil.

The expansion of urbanization on natural areas is increasing contact between human populations with wild animals. Wild carnivores can act as sentinel hosts or environmental health indicators. Thus, the aim of this work was to investigate the exposure of two major species of wild canids from Southern Brazil to selected pathogens. For that, we live-trapped free-ranging Cerdocyon thous and Lycalopex gymnocercus in five localities and determined the frequency of animals with antibodies against Toxoplasma gondii, Trypanosoma cruzi, Leishmania infantum, Neospora caninum, and Leptospira spp. Among the canids sampled, 23% (12/52) (95%CI: 13-36%) had antibodies against T. gondii, with titers ranging from 64 to 512. For T. cruzi, 28% (15/52) (95%CI: 18-42%) of sampled canids were seropositive, with titers ranging from 8 to 64. Concerning the protozoan pathogen N. caninum, a total of 5% (3/52) (95%CI: 2-15%) of wild canids had antibodies against it. None of the sampled canids showed the presence of antibodies against L. infantum. On the other hand, 44% (23/52) (95%CI: 31-57%) of the wild canids showed antibodies against Leptospira spp. The set of results presented here, show that free-ranging neotropical wild canids are exposed and have antibodies against to T. gondii, T. cruzi, Leptospira spp., and to a lesser degree to N. caninum. We found no evidence of L. infantum circulation among the studied populations. These results highlight some of the major pathogens which may represent risks for populations of these wild canids. DATA AVAILABILITY STATEMENT: The data that support the findings of this study are available from the corresponding author upon reasonable request.

Marine leech Ozobranchus margoi parasitizing loggerhead turtle (Caretta caretta) in Rio Grande do Sul, Brazil.

This paper reports the finding of several Ozobranchus margoi (Annelida: Hirudinea) parasitizing a loggerhead turtle (Caretta caretta) that was found in the municipality of Tavares, state of Rio Grande do Sul, southern Brazil. Since this parasite is considered to be a vector of chelonid herpesvirus 5 (ChHV-5), the leeches collected were tested for the presence of this virus. All the specimens were negative on PCR analysis. Although O. margoi is considered to be a common sea turtle parasite, this is the first official record describing collection of this parasite from a loggerhead turtle in southern Brazil, within the country's subtropical zone. This finding draws attention to the presence of this parasite and to the risk of leech-borne infectious diseases among turtles found along the coast of southern Brazil.

Marine leech Ozobranchus margoi parasitizing loggerhead turtle (Caretta caretta) in Rio Grande do Sul, Brazil / Sanguessugas Ozobranchus margoi parasitando uma tartaruga cabeçuda (Caretta caretta) no Rio Grande do Sul, Brasil

This paper reports the finding of several Ozobranchus margoi (Annelida: Hirudinea) parasitizing a loggerhead turtle (Caretta caretta) that was found in the municipality of Tavares, state of Rio Grande do Sul, southern Brazil. Since this parasite is considered to be a vector of chelonid herpesvirus 5 (ChHV-5), the leeches collected were tested for the presence of this virus. All the specimens were negative on PCR analysis. Although O. margoi is considered to be a common sea turtle parasite, this is the first official record describing collection of this parasite from a loggerhead turtle in southern Brazil, within the country's subtropical zone. This finding draws attention to the presence of this parasite and to the risk of leech-borne infectious diseases among turtles found along the coast of southern Brazil.

Este artigo relata a descoberta de vários exemplares de Ozobranchus margoi (Annelida Hirudínea) parasitando uma tartaruga cabeçuda (Caretta caretta) encontrada no município de Tavares, Rio Grande do Sul, sul do Brasil. Uma vez que esse parasito é considerado vetor do chelonid herpesvirus 5 (ChHV 5), as sanguessugas foram testadas para a presença deste vírus. Todas as amostras foram negativas pela análise de PCR. Embora o O. margoi seja considerado um parasito comum de tartarugas marinhas, este é o primeiro registro oficial que descreve a coleta deste parasita em uma tartaruga cabeçuda no sul do Brasil, dentro da zona subtropical do país. Este achado chama a atenção para a presença deste parasita e para o risco de sanguessugas transmitirem doenças infecciosas em tartarugas no litoral sul do Brasil.