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Background: Botanical substances such as essential oils (EOs) have demonstrated insecticidal properties and are a valid option for vector control. However, free EOs are unreliable as mosquito larvicides due their easy degradation by environmental exposure to ultraviolet light and higher temperatures. Here, we assessed the efficacy of a mosquito larvicide based on orange oil in a yeast-based delivery system against Aedes aegypti strains with different resistance status towards chemical neurotoxic insecticides. This larvicide preparation was physicochemically characterized in a previous report. Methods: Larvae of four Ae. aegypti strains from different regions of Brazil and different resistance profiles for deltamethrin (pyrethroid) and temephos (organophosphate) were tested against yeast-encapsulated orange oil (YEOO) in laboratory conditions for measurement of LC50 and LC90 values. The same assays were performed with the Belo Horizonte strain under environmental conditions (natural light and temperature). The resistance profiles of these strains were compared to the Rockefeller reference strain in all conditions. Results: YEOO was found to be a highly active larvicide (LC50 < 50 mg/L) against all Ae. aegypti strains tested in both laboratory conditions (LC50 = 8.1–24.7 mg/L) and environmental conditions with natural light and temperature fluctuation (LC50 = 20.0–49.9 mg/L). Moreover, all strains were considered susceptible (RR < 5) to YEOO, considering resistance ratios calculated based on the Rockefeller strain. The resistance ratios were only higher than 2.5 for LC90–95 of Belo Horizonte in the laboratory, probably due the higher heterogeneity associated with older egg papers (> 5 months). Conclusion: YEOO demonstrates high larvicidal activity against Ae. aegypti strains with resistant phenotypes for deltamethrin (PY) and temephos (OP). This larvicidal activity suggests the potential for the development of YEOO as an alternative intervention to synthetic insecticides in integrated vector management programs, for populations with resistance to commonly used insecticides. [ABSTRACT FROM AUTHOR]

Equine Protozoal Myeloencephalitis (EPM) is an infectious disease whose main agent is the protozoan Sarcocystis neurona. The parasite affects the central nervous system of horses and can cause neurological alterations like ataxia, paresis, muscle atrophy and changes in mental status. With wide distribution in the national territory, it is important that this disease is part of the differential diagnosis in animals of equine species, since equines with this disease can present from discrete signs, such as a slight decrease in performance, to serious neurological signs. That is why the veterinarian must understand its characteristics and effective diagnostic methods for its identification. A five-year-old Brazilian Sport Horse mare was attended in the city of Belo Horizonte, Minas Gerais, with a history of atrophy in the lumbar region and rump. Also, the presence of opossums on the farm where the animal lived was reported. In neurological examination, grade 2 motor incoordination was detected. The SAG ELISA test was performed, and a positive result was obtained. All findings and the positive test result corroborate the diagnosis of EPM, which led to the recommended treatment, and visible clinical improvement. The aim of this paper is to report a clinical case of EPM in a mare in the city of Belo Horizonte, Minas Gerais, Brazil, taking into account the importance of knowledge of the epidemiological, clinical, diagnostic and therapeutic aspects of disease. [ABSTRACT FROM AUTHOR]

Both global climate change and urbanization trends will demand adaptation measures in cities. Large agglomerations and impacts on landscape and natural environments due to city growth will require guided densification schemes in urban areas, particularly in developing countries. Human biometeorological indices such as the Universal Thermal Climate Index (UTCI) could guide this process, as they provide a clear account of expected effects on thermal sensation from a given change in outdoor settings. However, an earlier step should optimally include an adequacy test of suggested comfort and thermal stress ranges with calibration procedures based on surveys with the target population. This paper compares obtained thermal comfort ranges for three different locations in Brazil: Belo Horizonte, 20° S, Aw climate type; Curitiba, 25.5° S, Cfb subtropical climate, both locations in elevation (above 900 m a.s.l.); and Pelotas, at sea level, latitude 32° S, with a Cfa climate type. In each city, a set of outdoor comfort field campaigns has been carried out according to similar procedures, covering a wide range of climatic conditions over different seasons of the year. Obtained results indicate a variation of neutral temperatures up to 3 °C (UTCI units) as a possible latitude and local climate effect between the southern locations relative to the northernmost location. Low UTCI values were found in the two subtropical locations for the lower threshold of the thermal comfort band as compared with the original threshold. A possible explanation for that is a longer exposure to cold conditions as buildings are seldom provided with heating systems. [ABSTRACT FROM AUTHOR]