Quantification of ovine gammaherpesvirus 2 in clinical cases of cattle with sheep-associated malignant catarrhal fever.

Ovine gammaherpesvirus 2 (OvGHV2) produces sheep-associated malignant catarrhal fever (SA-MCF), a frequently lethal, lymphoproliferative disease that is characterized by widespread vascular lesions. Most studies that evaluated the viral load in tissues of animals with SA-MCF were done in the Northern Hemisphere, with scant information from the Southern part of the globe. This study investigated the viral load of OvGHV2 in the tissues of cattle and an underdeveloped fetus with SA-MCF from three distinct biomes of Brazil. All animals had clinical and histopathological manifestations consistent with SA-MCF. Molecular testing identified the OvGHV2 tegument protein and glycoprotein B genes in the tissues of all animals and the fetus. Viral quantification based on the DNA polymerase gene detected elevated loads of OvGHV2 in tissues with histopathological evidence of SA-MCF and organs with unknown histological data, except for the tissues of the fetus, where the viral load was comparatively reduced. The viral loads detected in multiple organs of cattle from this study with SA-MCF are consistent with those identified in different animal species from the USA and Europe. The detection of a low viral load of OvGHV2 in fetal tissue confirmed transplacental dissemination since elevated viral loads were detected in multiple tissues of the cow with SA-MCF. Furthermore, the elevated viral loads detected in the pulmonary tissues of cattle with interstitial pneumonia indicate that OvGHV2 is an inductor of pulmonary disease in cattle.

Characterization of ovine gammaherpesvirus 2 in a goat by nanoplate digital PCR and other diagnostic methods.

The Macavirus, ovine gammaherpesvirus 2 (OvGHV2), is the cause of sheep-associated malignant catarrhal fever (SA-MCF). Although SA-MCF occurs in a wide range of mammalian hosts, there are few descriptions of this disease and/or infection in goats. This report describes the findings observed in a goat that was infected by OvGHV2 and adds to the rare description of this infection in this animal species. A 6.5-year-old, female, Anglo Nubian goat, with a neurological syndrome, that was euthanized after severe esophageal obstruction was investigated to determine the cause of the brain disease. Histopathology revealed cerebral cortical edema, hemorrhagic rhombencephalitis, severe hepatic necrosis, and atrophic enteritis. An immunohistochemical (IHC) assay identified intracytoplasmic antigens of a malignant catarrhal fever virus (MCFV) within epithelial cells of the intestine, liver, lungs, and kidneys. A semi-nested PCR assay amplified the partial fragment of the OvGHV2 tegument protein gene from the intestine, confirming that the MCFV identified by IHC was OvGHV2. A qPCR assay that targeted the OvGHV2 polymerase gene revealed an elevated quantification cycle (Cq), while nanoplate-based digital PCR (dPCR) detected low viral copy load within the OvGHV2 DNA. Furthermore, the nucleic acids of several disease pathogens associated with diseases in ruminants were not amplified. However, the exact cause of the neurological syndrome remained obscure since nucleic acids of neurological disease pathogens such as bovine viral diarrhea virus, bovine alphaherpesvirus 1 and 5, Histophilus somni, and OvGHV2 were not detected from the brain. Collectively, the results of the Cq and dPCR confirmed that this goat was infected with a low viral load of OvGHV2, which probably was insufficient to induce the typical histopathological alterations and subsequent clinical manifestations associated with SA-MCF and/or infections by OvGHV2. Therefore, elevated viral loads of OvGHV2 would have been required for the development of histological lesions and/or clinical manifestations of SA-MCF in this goat. Furthermore, the dPCR methodology can be used for the efficient detection and quantification of OvGHV2 DNA in animals with or without clinical and/or histopathological evidence of SA-MCF. Additionally, since previous cases of OvGHV2 infections in goats did not have the typical clinical manifestations of SA-MCF, one wonders if this Macavirus can induce SA-MCF in goats.

Detection of Toxoplasma gondii DNA in milk of dairy cows from southern Brazil.

Consumption of unpasteurized cow's milk may be a transmission route for some pathogenic microorganisms, but there is little information about the risk of Toxoplasma gondii infection. Blood and milk samples were collected in a paired and random fashion from 106 dairy cows and bulk-tank milk samples were also collected from each of the six farms, in southern Brazil. Serum anti-T.gondii antibodies (IgG) were detected by an indirect fluorescent antibody test (IFAT) with a cutoff point of 1:64. Nested PCR targeting the ITS1 was performed on milk samples to detect the Sarcocystidae family, confirmed to be T.gondii by Sanger sequencing. The occurrence of anti-T.gondii antibodies in the herds was 14.1%, (15/106) with seropositive cows in all herds. Antibody titers in positive samples ranged from 64 to 128. T.gondii DNA was detected in 2.8% (03/106) of the milk samples. The ITS1 sequences generated in this study were ON809793 - ON809794 and the sequencing revealed 98-100% identity with T. gondii DNA sequences deposited in GenBank. All cows PCR positive for T.gondii in milk were negative for IgG antibodies in serum, suggesting that naturally infected cows may shed T. gondii in milk in the acute phase of infection. The results of this study demonstrate that T. gondii DNA may be detected in raw cow's milk, so the potential risks of lactogenic infection should be considered. The presence of T. gondii DNA in milk does not confirm that the protozoa are viable and infective, and further investigations into the role of cow's milk in the epidemiology of toxoplasmosis are needed.

Estrategias pedagógicas de literacidad: experiencia significativa en una Institución Educativa de Boyacá / Literacy pedagogical strategies: A meaningful experience in a Boyacá´s School (Colombia) / Estratégias pedagógicas de alfabetização: experiência significativa em uma Instituição de Ensino de Boyacá

Resumen (analítico): Este artículo presenta los resultados obtenidos en una investigación acción educativa de tipo cualitativo, realizada en una Institución Educativa Técnica rural en un municipio de Boyacá (Colombia), donde se realizó una intervención a partir de estrategias pedagógicas para fortalecer los niveles de literacidad, teniendo en cuenta el aprendizaje significativo en su diseño dado al bajo nivel de dichos estudiantes. El soporte teórico de la investigación fue la literacidad como desarrollo de competencias en comprensión y producción escritural en contexto. La unidad de análisis fue observación directa a 6 participantes, sus respectivas pruebas de entrada y salida y 5 talleres pedagógicos. Con los resultados logrados en la investigación se evidencian avances en la mayoría de las variables evaluadas; sin embargo, al valorar los resultados finales, algunos alumnos aún presentan dificultades.

Abstract (analytical): This paper shows the results obtained in a qualitative, educative action research carried out in a rural Technical Educational Institution in Boyacá Department (Colombia), where an intervention was made from pedagogical strategies to strengthen literacy levels, taking into account students´ meaningful learning in their design due to its students´ low level. The theoretical support of the research was literacy as the development of competences in comprehension and written production in context. The analysis unit was a direct observation to 6 participants, their entry and exit tests and 5 pedagogical workshops. With the results obtained in the research, progress is evidenced in most of the evaluated variables; however, some students still presenting difficulties when the final results are assessed.

Resumo (analítico): Este artigo apresenta os resultados obtidos em uma pesquisa de ação educativa do tipo qualitativa realizada em uma Instituição de Ensino Técnico rural em um município de Boyáca (Colômbia), onde foi feita uma intervenção a partir de estratégias pedagógicas para fortalecer os níveis de alfabetização, levando em consideração o aprendizado significativo em sua desenho dado o baixo nível de tais alunos. O suporte teórico da pesquisa foi a alfabetização como o desenvolvimento de competências em compreensão e produção de escrituras em contexto. A unidade de análise foi observação direta para 6 participantes, seus respectivos testes de entrada e saída e 5 workshops pedagógicas. Com os resultados obtidos na pesquisa, evidencia-se progresso na maioria das variáveis avaliadas; no entanto, ao avaliar os resultados finais, alguns alunos ainda têm dificuldades.