Histopathology and Ultrastructure Features of the Midgut of Adult Females of the Tick Amblyomma cajennense Fabricius, 1787 (Acari: Ixodidae) in Various Feeding Stages and Submitted to Three Infestations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Acquired resistance of horses to Amblyomma cajennense (Fabricius, 1787) ticks

Acquired immunity of horses to larvae, nymphs and adults of the Amblyomma cajennense tick was evaluated through three consecutive experimental infestations of tick-bite naive hosts. Data from these infestations were compared to those from field-sensitized horses and donkeys. It was observed that tick-bite naive horses developed a low level of resistance after two infestations as shown by a significant decrease in larval yield and a tendency for lower engorged weight of nymphs during third infestation. Ticks fed on field-sensitized horses had a similar biological performance to that observed on the third infestation of tick-bite naive horses but the mean engorged nymph weight was significantly lower than that of the first infestation from tick-bite naive horses. Donkeys presented the strongest resistance with significantly lower engorged weights of all instars and of the egg mass compared to the first infestation of tick-bite naive horses. Donkeys also displayed a significantly higher resistance than field-sensitized horses as demonstrated by significantly lower egg mass weights. Overall these results indicate that donkeys but not horses maintain a strong resistance to A. cajennense ticks. The importance of these findings in relation to vectoring of tick-borne diseases is discussed. (C) 2003 Elsevier B.V. All rights reserved.

Innate Immunity in Wooless Lamb to Larvae of Amblyomma cajennense Tick (Fabricius, 1787) (Acari: Ixodidae)

P>The Cayenne tick Amblyomma cajennense infests preferably horses in its adult form but other mammal species in its immature stages and is the main vector of Rickettsia rickettsii, the Brazilian spotted fever pathogen. As wooless lambs are often raised on pasture together with horses, an experiment was performed to investigate their possible acquisition of resistance to A. cajennense after experimental infestations. Seven naive wooless lambs were infested thrice at 60 days interval with immature and adult instars of A. cajennense from a laboratory colony, the tick biotic potential being determined and biopsies of tick bite lesions taken to investigate the inflammatory cell component. Nearly 100% of larvae died in all infestations, while nymphs and adults fed normally throughout re-infestations. Microscopic features of adult tick bite lesions revealed predominance of neutrophils (38%) and eosinophils (36.8%), respectively, in the first and second infestations. In the third infestation, 43.6% of MN cells were found and about 31% of eosinophils. on the other hand, nymph bite lesions revealed in all infestations a predominance of eosinophils, increasing from 36% in the first infestation to 50.5% in the third one. It is concluded that wooless lambs present remarkable innate resistance against larvae of A. cajennense, but marked susceptibility to the other tick instars despite the migration of great number of eosinophils to the tick lesion.

Estimación de la mortalidad adulta a partir de la información sobre la estructura por edad de las muertes: aplicación a datos de San Felipe en torno a 1787

Incluye Bibliografía

Adult mortality estimate based on information on age structure of deaths, and application to data for San Felipe around 1787

Includes bibliography

Estimacion de la mortalidad adulta a partir de informacion sobre la estructura por edades de las muertes: aplicaciones a datos de San Felipe en torno a 1787

Incluye Bibliografía

Estimación de la mortalidad adulta a partir de la información sobre la estructura por edad de las muertes: aplicación a datos de San Felipe en torno a 1787

Incluye Bibliografía

Influência da sinigrina no comportamento de busca e seleção de presas pelo predador Orius insidiosus (Say, 1832) (Hemiptera: Anthocoridae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aspectos biológicos e taxa de consumo de Orius insidiosus (Say, 1832) (Hemiptera: Anthocoridae) predando Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resposta funcional e numérica do predador Orius insidiosus (Say, 1832) (Hemiptera: Anthocoridae) com diferentes presas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tradução anotada de Les infortunes de la vertu (1787), do Marquês de Sade (1740-1814)

Pós-graduação em Letras - FCLAS

Avaliação da resistência em caprinos a ninfas do carrapato Amblyomma cajennense (Fabricius, 1787) e da reatividade cruzada com A. hebraeum (Koch, 1844) (Acari:Ixodidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análise molecular e morfológica de exemplares de Trichomycterus valenciennes, 1832 da Chapada dos Guimarães (Bacia do Paraguai) e ensaio sobre o complexo de espécies Trichomycterus brasiliensis Lutken, 1874

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo morfofisiológico dos ovários e do corpo gorduroso do carrapato-estrela Amblyomma cajennense Fabricius (1787) (Acari : Ixodidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Histopatologia e ultraestrutura do intestino de fêmeas adultas do carrapato-estrela Amblyomma cajennense Fabricius, 1787 (Acari : Ixodidae) durante alimentação em coelhos pré-sensibilizados

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC