Banca de DEFESA: LEO PAULIS MENDONÇA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : LEO PAULIS MENDONÇA
DATA : 05/03/2020
HORA: 09:00
LOCAL: Sala 24 do Departamento de Parasitologia Animal
TÍTULO:

Molecular detection of Ehrlichia canis (Donatien, Lestoquard, 1937) in his invertebrate host Rhipicephalus sanguineus (Acari: Ixodidae) (Latreille) collected in municipalities with different altitudes in the southeastern state of Rio de Janeiro

PALAVRAS-CHAVES:

Ehrlichia canis, Rhipicephalus sanguineus, altitude, epidemiology, qPCR

PÁGINAS: 44
GRANDE ÁREA: Ciências Agrárias
ÁREA: Medicina Veterinária
SUBÁREA: Medicina Veterinária Preventiva
ESPECIALIDADE: Doenças Parasitárias de Animais
RESUMO:

Ticks are vectors of diseases of great importance for human and veterinary health. The ticks
of the group Rhipicephalus sanguineus sense lato (s.l.), known as "common dog tick", are
under investigation for their exact taxonomic position, and more recently using molecular
techniques it was determined that there are two different lineages, in which they are addapted
to the climate in which they live, temperate or tropical. Monocytic Canine Ehrlichiosis (EMC)
is a disease transmitted by ticks Rhipicephalus sanguineus of tropical lineage, caused by the
intramonocytic agent Ehrlichia canis and has great importance for the health of dogs and a
new zoonotic profile still under investigation, being diagnosed very often in veterinary
establishmensts. The present study deals with an epidemiological investigation, using a realtime
PCR technique (qPCR) to detect the agent in question in tests of tick organs collected at
different altitudes in the State of Rio de Janeiro. Monthly surveys were made to the
municipalities of Paracambi, Barra do Piraí, Petrópolis and Teresópolis, visiting random
residences in the urban and rural areas of each municipality and selected for dogs, after being
allowed to participate in studies, who answered an epidemiological questionnaire using
information about animals and the environment at the time. Ticks were searched for 15
minutes in animals and 15 minutes in the environment, conditioned in test tubes capped with
cotton, identified and dissected the next day. The organs of each tick were stored in
preservative RNAlater® in 1.5 ml microtubes at -20 ° C until the extraction of the genetic
material. In all, 412 ticks were collected, among which 86 engorged females of R. sanguineus
that were dissected. Detection of the agent using qPCR revealed a positivity of 15 out of 86
dissected ticks (17.71%), and among the organs, 15 out of 86 cuts of the intestine and salivary
gland were positive (17.71%), while only 10 among 86 ovary samples were positive
(11.62%). Variables intrinsic to animals were did not influence in the infection of their ticks
by E. canis. Ticks in the dry season were 3.97 times more likely to be infected with E. canis
than in the rainy season (CI: 0.89 - 17.71, p <0.05). Ticks collected at altitudes above 650 m.
were 2.86 times more likely to be infected by E. canis than ticks collected at altitudes below
650 m (CI: 0.9 - 9.15, p = 0.05). The strain of ticks involved in the transmission of E. canis
under the conditions of the present study was found to be tropical through digestion by
restriction enzymes of an amplified product of mitochondrial DNA that transcribes into the
16S subunit of the ribosomal RNA (16S rRNA).

MEMBROS DA BANCA:
Presidente - 386163 - CARLOS LUIZ MASSARD
Externa ao Programa - 3103528 - CLAUDIA BEZERRA DA SILVA
Externa ao Programa - 3103478 - MARISTELA PECKLE PEIXOTO
Externo à Instituição - DANIEL DA SILVA GUEDES JUNIOR - FIOCRUZ
Externa à Instituição - ERICA CRISTINA ROCHA ROIER - UV