Dermatite alérgica sazonal em ovinos deslanados no nordeste do Brasil

Allergic Dermatitis in Pêga Breed Donkeys (Equus asinus) Caused by Culicoides Bites in the Amazon Biome, Pará, Brazil

An allergy to bites from Culicoides (Diptera: Ceratopogonidae) occurs because of a hypersensitivity reaction caused by the inoculation of insect salivary antigens during the bite, resulting in immune-mediated dermatitis. To the best of our knowledge, no previous studies have focused on allergic dermatitis in donkeys in Brazil. Therefore, this study aimed to describe the epidemiological, clinicopathological, and therapeutic aspects of allergic dermatitis in donkeys and to identify the insects involved in its epidemiology. This study reported the occurrence of dermatitis in 17 animals. The clinical signs were restlessness and severe itching. Skin lesions were found on the head, depigmented areas of the muzzle and cheeks, flanks, pelvic and thoracic limbs, and the scrotal sac. The lesions were characterized by areas of alopecia with crusts accompanied by serosanguineous exudates. Histologically, the lesions were characterized as moderate superficial dermatitis with irregular epidermal acanthosis and pronounced diffuse orthokeratotic hyperkeratosis. In total, 378 Culicoides specimens were collected, with Culicoides ocumarensis Ortiz being the most abundant species. The combined application of copaiba oil and a multivitamin emulsion exhibited potential for topical treatment of allergic dermatitis caused by insect bites in donkeys. Our study revealed an association between allergic dermatitis in donkeys and Culicoides.

Influence of meteorological and seasonal parameters on the activity of Culicoides paraensis (Diptera: Ceratopogonidae), an annoying anthropophilic biting midge and putative vector of Oropouche Virus in Rondônia, Brazilian Amazon

Biting midges of the genus Culicoides are insects of proven medical and veterinary importance, because of their role in the transmission of viruses, bacteria, protozoa and nematodes. Culicoides paraensis has been considered the main vector of the Oropouche Virus (OROV) in the urban cycle of the disease in the neotropics. Due to the great abundance of Culicoides spp. in the State of Rondônia and its epidemiological history of OROV, we investigated the biting activity in humans, the abundance as a function of meteorological parameters and seasonality, and the detection of OROV. Entomological collections occurred in three municipalities from Brazilian State of Rondônia: Porto Velho, Ariquemes, and Ouro Preto do Oeste. GLMM's were used to determine if Culicoides spp. abundance was predicted by seasonal, diurnal, and meteorological factors. Total RNA was extracted from insects and viral RNA detection was performed using the S segment as the target region of OROV via RT-qPCR. In total, 7,315 individuals were captured and identified as C. paraensis. In the dry season, 1,488 individuals (24.5%) were recorded, 4,591 (75.5%) in the rainy season, with peaks of biting activity between 4pm and 6pm. All variables showed a significative effect on the midge abundance. The rainy season, temperature between 30°C and 32°C and relative air humidity between 75% and 85% were the main predictive parameters for capturing the highest average number of insects. Our results confirm diurnal activity of C. paraensis and its greatest abundance in rainy periods. No sample was positive for the OROV, which could be explained by the virus absence in local human populations, C. paraensis as a minor vector species in the sampled localities, and probable low rate of infection of biting midges. Our findings on hourly and seasonal biting activities can provide support to intervention actions regarding vector control and surveillance of this species. This was the first study to collect and analyze biting midges in a region where human OROV cases had already been detected, but without previous information on entomovirological surveillance.

Doenças de pele em equídeos no semiárido brasileiro

As doenças que acometem a pele e anexos de equídeos no semiárido nordestino foram analisadas mediante um estudo retrospectivo dos registros de atendimento na Clínica de Grandes Animais do Hospital Veterinário da Universidade Federal de Campina Grande, de janeiro de 2002 a dezembro de 2012. Dos 2.054 atendimentos 1.786 eram equinos, 200 eram asininos e 58 eram muares. Os diagnósticos de dermatopatias totalizaram 535 casos (26,05%) dos quais 447 foram em equinos, 68 em asininos e 20 em muares. Nos equinos as dermatopatias mais frequentes foram a pitiose (24,38%), as feridas traumáticas (23,04%), os abscessos (12,75%), o tecido de granulação (8,5%) e a habronemose (7,38%). Juntas essas enfermidades totalizaram 76,05% dos diagnósticos de dermatopatias para essa espécie. Em asininos as doenças mais frequentes foram feridas traumáticas (47,5%), sarcoide (19,11%) e abscessos (13,23%). Estas enfermidades juntas representaram 79,84% das doenças de pele nesta espécie. Os muares apresentaram feridas traumáticas em 30% dos casos e carcinoma de células escamosas e habronemose em 15% cada. As três enfermidades representaram 60% dos diagnósticos de doenças de pele nesta espécie. Conclui-se que as doenças de pele são uma das principais causas de atendimento clínico em equídeos na região semiárida do nordeste do Brasil e os conhecimentos gerados neste estudo são importantes para o reconhecimento, diagnóstico e tratamento das mesmas.