Alimenta??o de Ornithodoros rostratus (Acari: Argasidae) por meio de membranas de silicone: par?metros biol?gicos e infec??o in vitro de Rickettsia parkeri

• Autor(a) principal: Ribeiro, Carla Carolina Dias Uzedo
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/jspui/2825
• topic: Carrapato; Argasidae; Alimenta??o Artificial; Infec??o Experimental; Medicina Veterin?ria

Artificial feeding is an important tool for enabling studies involving the intrinsic relationship vector - pathogen, and mimic the use of natural hosts. The aim of the first chapter was to establish the artificial feeding of the species O. rostratus using silicone membranes and evaluate the effect of diet in the biological parameters of the ticks fed artificially. In the second chapter, was to evaluate the efficiency of the technique described in the first chapter in the infection in vitro of R. parkeri by tick nymphs of O. rostratus and verify the potential for transmission of R. parkeri by infected tick nymphs to susceptible hosts was verified as well as the possibility of pathogen isolation in culture. The first experiment was initiated with 130 ninfal first instar nimphs of O. rostratus individualized for each experimental group. The groups were divided according to the given diet, namely, citrated rabbit blood, citrated bovine blood, bovine blood with antibiotics and defibrinated bovine blood. The control group was fed directly in rabbits.The specimens were weighed before and after artificial feeding, wich was carried out in an apparatus made of silicone membranes. In the second chapter, 42 nymphs in diferent instars were used, with homogeneous weights, divided into three groups. Group 1 was directed to the assessment of the artificial feeding technique in the infection in vitro of R. parkeri to O. rostratus nymphs and group 2 was used to evaluate the transmission capacity of Rickettsia parkeri to guinea pigs by artificially infected O. rostratus nymphs. Group 3 was the control group. Groups 1 and 2 were artificially fed with rabbit blood containing 5 x 105 of VERO cells infected with R. parkeri. PCR was performed to assess infection in group 1 ticks. Evaluation of infection in guinea pigs was carried out by the IFA technique, and clinical signs presented by the hosts. The results of the first experiment showed that the proposed feed apparatus was efficient concerning fixation stimulus and satisfactory in engorging ticks, as being possible to maintain colonies of Ornithodoros rostratus using artificial feeding only through silicon membrane. Ticks that received citrated rabbit blood showed biological parameters similar to those in vivo conditions. The second study demonstrated that the artificial feeding system was able to promote the infection in vitro of R. parkeri to O. rostratus tick nymphs, in addition to verifying that adult O. rostratus infected by R. parkeri by artificial means is able to infect guinea pigs.