RESUMO
Many studies about fasciolosis control have been carried out, whether acting on the adult parasite or in Pseudosuccinea columella, compromising the development of the larval stages. The present study aimed to evaluate, under laboratory conditions, the susceptibility of P. columella to Heterorhabditis bacteriophora HP88, during for 24 and 48 hours of exposure. The snails were evaluated for 21 days for accumulated mortality; number of eggs laid; hatchability rate; biochemical changes; and histopathological analysis. We found that exposure induced a reduction in glucose and glycogen levels, characterizing a negative energy balance, due to the depletion of energy reserves as a result of the direct competition established by the nematode/endosymbiont bacteria complex in such substrates. A mortality rate of 48.25% and 65.52% was observed in the group exposed for 24 h and 48 h, respectively, along with significant impairment of reproductive biology in both exposed groups in relation to the respective controls. The results presented here show that P. columella is susceptible to the nematode H. bacteriophora, with the potential to be used as an alternative bioagent in the control of this mollusk, especially in areas considered endemic for fascioliasis, in line with the position expressed by the World Health Organization Health.
Assuntos
Fasciolíase , Rabditídios , Animais , Controle Biológico de Vetores/métodos , Caramujos/parasitologia , Fasciolíase/veterináriaRESUMO
The city of Guarapari, known as "Healthy City", has as its main tourist attraction radioactive sands known as monazite sands. There are many studies aimed at quantifying radiation, but little is known about an influence of radiation levels on the life cycle of parasites with zoonotic potential, since many owners take their animals to beaches facilitating a maintenance of their cycle. The objective of the present work was to evaluate the association of the sand radiation of the beaches of the municipality of Guarapari and the presence of eggs and larvae of zoonotic potential parasites. To determine the influence of the radiation on the parasites, sand and faeces samples were collected from the beaches of Praia do Morro, Areia Preta, Castanheiras, Setiba and Santa Mônica, and how to analyze, use the simple centrifugal-flotation technique. The beaches of the present study were classified as low, medium and high radioactivity according to the dose limits that a human being can receive. The samples of sand and faeces were grouped according to a classification of the beaches where they were collected as samples. After obtaining the result, a Chi-square statistical test was performed at a significance level of 95% to evaluate an association between radiation classes and parasite presence. In general, monazitic sands have an influence on the maintenance of the cycle of zoonotic parasites found in beach sand, their correlation being inversely proportional.
O município de Guarapari, balneário conhecido por "Cidade Saúde", possui como principal atrativo turístico as areias radioativas conhecidas como areias monazíticas. Há muitos estudos direcionados a quantificação da radiação, mas pouco se sabe sobre a influência dos níveis de radiação sobre o ciclo de vida dos parasitos com potencial zoonótico, uma vez que muitos proprietários levam seus animais as praias, facilitando a manutenção desses ciclos. O objetivo deste trabalho foi avaliar a associação da radiação da areia monazítica das praias do município de Guarapari e a presença de ovos e larvas de parasitos de potencial zoonótico. Para determinar a influência da radiação sobre os parasitos, coletou-se amostras da Praia do Morro, Areia Preta, Castanheiras, Setiba e Santa Mônica, a partir de areias e de fezes, para a análise utilizou a técnica de centrifugo-flutuação simples. As praias deste estudo foram classificadas em baixa, média e alta radioatividade de acordo com as doses limites que um ser humano pode receber. As amostras de areia e fezes foram agrupadas de acordo com a classificação das praias onde foram recolhidas as amostras. Após obtenção do resultado, foi feito teste estatístico Qui-quadrado a um nível de significância de 95% para avaliar a associação entre as classes de radiação e a presença dos parasitos. Em geral, as areias monazíticas têm influência na manutenção do ciclo de parasitas zoonóticos encontrados na areia da praia, sendo sua correlação inversamente proporcional.