An investigation on the digenetic trematodes parasitizing free range reared guinea fowls was conducted in the state of Rio de Janeiro, Brazil, based on clinical examination, necropsies and histopathologica l findings in 36 guinea fowls. Parasites, prevalence and intensity of infection were, respectively: Paratanaisia bragai, 61.1% and 31 (in each kidney); Athesmia heterolecithodes, 8.3% and 38; Conspicuum conspicuum, 2.8% and 1. A. heterolecithodes was highly pathogenic to guinea fowls, causing severe hepatic lesions. However, C. conspicuum and P. bragai were less pathogenic in the considered intensities of infection. This is the first time that these parasite species have been reported in Brazilian guinea fowls.

SUMMARYExperiments were carried out with Sw albino mice and it was concluded that the percutaneous route via abdominal skin was significatively more efficient than tail immersion method and subcutaneous infection; the subcutaneous injection was significatively more efficient than the percutaneous infection through the tail; this latter and the intraperitoneal injection, resulted in similar infections, but were significatively less efficient than the others. Significative difference was also observed in the comparison between the subcutaneous route and percutaneous infection through ear pinna. The influence of the site of skin infection by percutaneous route was also discussed.

Previous work in our laboratory, mainly focused the prospects of achieving resistance against Schistosoma mansoni infection with adult worm-derived antigens in the form of a soluble extract (SE). This extract obtained by incubation of living adult schistosomes in saline, contains a large number of distinct molecules and was actually shown to be significantly protective in different outbred animals models such as Swiss mice and rabbits. It thus appeared worthwhile to investigate the potential protective activity of SE in different inbred strains of mice, known to be highly susceptible to the infection. Herein we present data showing that DBA/2 mice, once immunized with SE acquire significant levels of resistance to a S. mansoni cercarial challenge. In addition, preliminary studies on the immune system of immunized animals revealed that, injection of SE caused no general imbalance of B or T cell responses.