Banca de DEFESA: THIAGO DOS SANTOS CARDOSO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : THIAGO DOS SANTOS CARDOSO
DATA : 24/09/2019
HORA: 10:00
LOCAL: Sala 14
TÍTULO:

Influence of biotic and abiotic factors in the metacomunity structures of helminth parasites of small mammals in the Serra dos Órgãos National Park, state of Rio de Janeiro, Brazil.

PALAVRAS-CHAVES:

biodiversity; communities; parasitism;

PÁGINAS: 138
GRANDE ÁREA: Ciências Agrárias
ÁREA: Medicina Veterinária
RESUMO:

Parasites are widely distributed organisms and play a key role in biodiversity, because they can regulate host populations, interfere with other types of ecological interactions, alter an ecosystem by the cascade effect, and even influence evolutionary patterns of hosts. The objective of this thesis was to analyse the structure of helminth metacommunities in small mammal species, investigating the influence of biotic and abiotic factors on the species composition of these parasites in the Serra dos Órgãos National Park (PARNASO), state of Rio de Janeiro. Rodents and marsupials were collected in linear transects at three locations. The influence of biotic (age and sex of the host) and abiotic factors (municipality of samplings) on the parasitological parameters of the most prevalent helminth species were investigated. The metacommunity structures of small mammals and helminths were analysed using the Analysis of Metacommunity Structure. The influence of environmental variables, represented by microhabitat, and spatial variables, calculated from geographic coordinates, in the helminth species composition was also investigated. Twenty species of small mammals were captured, of which 12 were parasitized by helminths. In total, 29 species of helminths belonging to the Nematoda, Platyhelminthes and Acantocephala phyla were recovered. The species Aspidodera raillieti, Cruzia tentaculata, Turgida turgida and Viannaia hamata presented the highest values of prevalence and / or abundance in the marsupial Didelphis aurita, such as the species Stilestrongylus aculeata, in the rodent Akodon montensis, and Stilestrongylus lanfrediae, in the rodents Oligoryzomys flavescens and Oligoryzomys nigripes. Some helminth species were influenced by sex and age of the hosts as well as by the sampling locality. Greater sharing of helminth species was observed between phylogenetically and / or ecologically related hosts, corroborating the importance of host-parasite coevolution in species composition. Akodon montensis seems to act as a keystone species in the community, sharing helminths species with other rodents. However, D. aurita was the species with the highest total and mean species richness of helminths. Only the metacommunity of helminths considering rodents and marsupials together at the infracommunity level presented a non-random structuring pattern, with a quasi-Gleasonian structure being recorded. This pattern indicates that the species respond to the same environmental gradient, but individually, with species replacements instead of losses along the gradient. The helminth species composition of this metacommunity varied as a function of both the environmental gradient, indicated by the variables watercourse and understory, as well as the spatial one, indicating that differences among localities were higher than on a local scale. The results indicated that the metacommunity of these studied parasites was influenced not only by the taxonomic groups of hosts, but also by abiotic factors and spatial scales investigated.

MEMBROS DA BANCA:
Externo à Instituição - CLAUDIA PORTES SANTOS SILVA - FIOCRUZ
Presidente - 2242796 - JOSE LUIS FERNANDO LUQUE ALEJOS
Externo à Instituição - LUIZ EDUARDO ROLAND TAVARES - UFG
Externo à Instituição - NATALIE OLIFIERS - UVA
Externo à Instituição - PEDRO CORDEIRO ESTRELA DE ANDRADE PINTO - UFPB
Externo ao Programa - 3092534 - RAQUEL DE OLIVEIRA SIMOES