Banca de DEFESA: PRISCILLA NUNES DOS SANTOS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : PRISCILLA NUNES DOS SANTOS
DATE: 23/06/2020
TIME: 09:00
LOCAL: VIRTUAL POR VÍDEO CONFERENCIA
TITLE:

Analysis of the evolution of Anaplasma marginale msp1α gene in calves and ticks and Propagation and characterization of an Anaplasma marginale isolate from Portugal in IDE8 cells

KEY WORDS:

Keywords: Diversity, Rhipicephalus microplus, IDE8, msp1α.

PAGES: 112
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Medicina Veterinária Preventiva
SPECIALTY: Doenças Parasitárias de Animais
SUMMARY:

This thesis consists of two chapters: The purpose of the first chapter was to evaluate the tandem repeat diversity in the major surface protein MSP1a of Anaplasma marginale in experimentally infected cattle and in Rhipicephalus microplus over the span of 1 year, and re-isolation of the A. marginale AmRio1 strain from cattle leukocytes was performed. The second chapter was aimed at isolating, propagating, and characterizing a novel Anaplasma sp. genotype from Portugal in IDE8 cells. To evaluate A. marginale genetic diversity, cattle were infested with R. microplus larvae and subsequently infected by A. marginale from tick cell cultures. The strains AmRio1 and AmRio2 were inoculated in bovine 1 and bovine 2, respectively. Subsequently, blood samples were collected over 1 year for blood smears, hematocrit, plasma proteins, and semi-nested polymerase chain reaction (PCR) for the msp5 and msp1α genes. A. marginale was also isolated from the cattle leukocytes. Ticks were collected and their salivary gland and gut DNA were tested using semi-nested PCR for the msp5 and msp1α genes. Both animals showed stability in the evaluated parameters and absence of clinical signs, showing that they had persistent infection. A blood smear from Animal 1 showed inclusions inside the leukocytes, and four attempts were made to isolate Anaplasma sp. from leukocytes for the inoculum. Animal 1 became positive for the msp5 gene on day 12 after infection, while positivity was detected in Animal 2 only 77 days after second exposure to the agent. The tandem repeats were stable when the blood and tick samples of both animals were evaluated, demonstrating the presence of the strains AmRio1 in Animal 1 and AmRio2 in Animal 2. In the second chapter, erythrocytes from a naturally infected bovine from Portugal were used for isolating Anaplasma sp. in IDE8 cells. Suggestive inclusions of infection were observed in the IDE8 cells 35 days after inoculation. The Anaplasmataceae family 16S rRNA gene from the cultures was sequenced, and showed that the isolated rickettsia was close to the A. platys species in the phylogenetic tree.

BANKING MEMBERS:
Presidente - 385857 - ADIVALDO HENRIQUE DA FONSECA
Interno - 3701492 - HUARRISSON AZEVEDO SANTOS
Interno - 386163 - CARLOS LUIZ MASSARD
Externa ao Programa - 3103478 - MARISTELA PECKLE PEIXOTO
Externo à Instituição - ERICH PETER ZWEYGARTH
Externa à Instituição - BRUNA DE AZEVEDO BAETA - UV
Externa à Instituição - PATRICIA BARIZON CEPEDA - UBM