Data/hora: 04/06/2024 13:14:17

Biblioteca(s): 	Embrapa Cerrados.	
Data corrente: 	23/04/1999	
Data da última atualização: 	23/04/1999	
Autoria: 	COSTA, C. A. F.	
Título: 	Infection of Fasciola hepatica (Digenea: Fasciolidae) with Nosema algerae (Microsporida: Nosematidae) during development in Lymnaea cubensis (Basommatophora: Lymnaeidae).	
Ano de publicação: 	1978	
Fonte/Imprenta: 	Florida: University of Florida, 1978.	
Páginas: 	96p.	
Idioma: 	Inglês	
Notas: 	Tese Mestrado.	
Conteúdo: 	The susceptibility of Lymnaea cubensis (a natural vector of Fasciola hepatica) and F. hepatica larvae to infection with Nosema algerae, a microsporidian pathogen of mosquitoes was investigated. Possible influences of prior F. hepatica infection on the snail susceptibility to N. algerae were also studied. A method for laboratory colonization of L. cubensis was developed and evaluated, based on snail mortality and metacercariae production after F. hepatica infection. The infectivity of F. hepatica miracidia, from a common source, to L. cubensis snails from 2 different regions of Florida (Palatka and Clewiston) was established. The snail mortality recorded during a 50-day period was 10% and metacercariae production in snails with 50-day old F. hepatica infections averaged 31.6 metacercariae per snail. The infectivity of F. hepatica miracidia to snails from the Palatka and Clewiston areas was significantly (p<0.01) different with the snails from Palatka more susceptible. In the infectivity studies of N. algerae to L. cubensis that were infected with F. hepatica larvae, 38% were found to harbor F. hepatica larvae with microsporidian infections. However, in the snails with infected trematode larvae only about 60% had microsporidian stages in their tissues. It could not be established if these represented true infections or had been released from the larvae during dissection. Control snail groups, not exposed to N. algerae spores, but either infected or non-infected with F. hepatica, did not show microsporidia infrections when dissected. The percentage of snails harboring microsporidia- infected F. hepatica larvae increased as the interval between exposure to N. algerae and examination for infection also increased. During the time of dissection, most microsporidian infections were light and could not be associated with pathological changes in the infected trematode rediae. The life cycle of the microsporidium was determined and compared with that of N. algerae and other microsporidia previously reported in the snail-trematode system. Based on incidence and morphological findings, the successful transmisson of N. algerae, a mosquito pathogen, to F. hepatica rediae in L. cubensis was accomplished. This is the first report of a microsporidium from arthropods hyperparasitizing trematode larvae in snails.	
Palavras-Chave: 	Lymnaea cubensis.	
Thesagro: 	Fascíola Hepática; Parasito; Trematódeo.	
Thesaurus Nal: 	Nosema algerae; parasites; Trematoda.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Cerrados (CPAC)	
Exemplares: 	CPAC - (19623-1) - ADD - TS - -- - T024/78 - COS - T024/78 - DIS