The genus Rhipicephalus includes about 70 tick species, almost all of them originating from the Afrotropical region, and among which are included the brown dog tick R. sanguineus and the cattle tick R. microplus, which in addition to causing mechanical damage to the host, also transmit pathogens of great importance in animal and public health. Tick control based on chemical acaricides has led to the rapid development of ectoparasite resistance as well as environmental and animal products contamination. Given these facts, there is an increasing search for alternatives to tick control, such as the development of vaccines. The present study aims, through a research agreement with the United States Department of Agriculture/Agricultural Research Service (USDA/ARS), to evaluate the use of a recombinant tick protein from R. microplus Aquaporin as an antigen in a vaccine against R. sanguineus in domestic dogs. The vaccine´s effects will be evaluated on the different stages of the ectoparasite in dogs previously vaccinated with antigen + adjuvant (Montanide) (G1) and a control group of animals inoculated with adjuvant only (G2). It will be evaluated: i. biotic potential (biological parameters) of the ticks, ii. serum antibody titers of dogs through indirect immunosorbent assay (ELISA test) after immunization; iii. antigen sites of action in the body of the tick by immunohistochemical assay, iv. histopathology of the ticks for observation of possible damages caused by the action of the immunogen; v. histopathological examination of the ticks´ attachment sites at different times post-fixation to the skin of the host, including inflammatory cells count that migrated into the inflammatory focus.
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