Suchergebnisse

Maedi-Visna (MV) is a chronic progressive multisystem disease that may be asymptomatic for several months or years, but progress rapidly, and may result in death, when signs and symptoms evolve. Viral elimination occurs mainly through direct contact with positive animal secretions. There is no vaccine or treatment, and prophylaxis is necessary for the health of the herd. The present study aimed to verify the seropositivity of MV and evaluate the factors associated with the risk in sheep herds in Paraná. A total of 1549 serum samples were collected from 90 properties. An epidemiological questionnaire was applied to each property, and the variables were analyzed using the Epi-info program and R environment. Of the 1549 samples analyzed, 22 were positive (1.4%) for the micro-AGID test in 13.3% of the properties. Our study demonstrated variables associated with the prevention and the risk of seropositivity to MVV. Conducting a breeding season, supplying concentrated feed, and separating the breeding stock before birth were factors associated with protection, whereas the previous occurrence of problems with lice, breeding on pasture, and keeping cats close to the flock were factors associated with risk. The seropositivity observed in the present study suggests the circulation of MVV in sheep herds in Paraná, which reinforces the need to implement prevention and control measures since the level of technification may be associated with the occurrence of anti-MVV antibodies in herds.

Neosporosis, caused by the protozoan Neospora caninum, has been widely reported and discussed as a major disease associated with reproductive problems in herds of various animal species. This study aimed to perform a systematic review and meta-analysis on the prevalence and risk factors associated with ovine neosporosis worldwide. This is the first systematic review, which was performed according to the established preferred reporting items in systematic reviews and meta-analyses (PRISMA) guidelines to address ovine neosporosis. Four databases were used in this study: PubMed, SciELO, Web of Science, and Scopus. The selected keywords were "neospora AND sheep," "neosporosis AND sheep," "neospora AND lamb," "neosporosis AND lamb," "neospora AND ewe," and "neosporosis AND ewe." The meta-analysis calculations were performed with random-effects models for proportions, and heterogeneity was tested using the I2 test. This study identified 24 studies on ovine neosporosis, nine of which evaluated the factors associated with the risk of seropositivity. After meta-analysis, the pooled estimated prevalence was 12% (95% CI, 8-16%; I² p-value < 0.01). The evaluation of the included studies allowed the identification of ovine neosporosis distribution in continents according to demonstrated prevalence rates. We confirmed via metaanalysis that the use of indirect immunofluorescence assay (IFAT) or enzyme-linked immunosorbent assay (ELISA) in the diagnosis of ovine neosporosis was not a source of data heterogeneity. The presence of dogs on the properties was reported as the main risk factor associated with the occurrence of ovine neosporosis; however, this was not confirmed by the meta-analysis.