Trypanosoma nupelianus sp. n. (Protozoa, Kinetoplastida) parasitizing rhinelepis aspera (Osteichthyes, Loricariidae) from Paraná river, Brazil

It is described Trypanosoma nupelianus sp. n. parasitizing Rhinelepis aspera taken from Paraná river (Itaipu reservoir, Brazil). Morphometric characters such as body length, width of the body and nucleus dimensions show that T. nupelianus sp. n. is different from other trypanosomes described for fishes from tropical regions

Trypanosomes of Brazilian fishes. II. Trypanosoma barrettoi sp. n. from Hypostomus paulinus (Siluriformes, Loricariidae).

Trypanosoma barrettoi sp.n. is described from the blood of the armored catfish Hypostomas paulinus Ihering, from the State of São Paulo, Brazil. The total length averages 40.22 microns, of which 14.22 microns is free flagellum.

Comportamiento de la infección y diferenciación morfologica entre trypanosoma cruzi y T. rangeli en el intestino del vector Rhodnius prolixus / Course of the infection and morphological differentiation between trypanosoma cruzi and T. rangeli in the intestine of the vector Rhodnius prolixus

A distribuiçäo de amastigotas, epimastigotas, esferomastigotas e tripomastigotas foi estudada no intestino de Rhodnius prolixus infectado com Trypanosoma cruzi (amostra Molino) e T. rangeli (amostra San Agustín). Medidas foram feitas de 500 cinetoplastos de organismos morfologicamente diferentes para verificar se é possível identificar as espécies usando esse caracter. A maioria dos tripomastigotas de cada espécie foi diferenciada pelo comprimento do corpo e o tamanho do cinetoplasto. Porém, em algumas infeccöes por T. rangeli, foi observado que menos de 1% dos epimastigotas curtos eram morfologicamente idênticos às mesmas formas de T. cruzi. Nesses casos o T. rangeli pode ser confundidos com T. cruzi, e que poderia ter graves implicaçöes

Morphological and biological features of Trypanosoma (Herpetosoma) mariae Mello, 1978 in experimentally infected Calomys callosus.

In this paper some observations on the biology of Trypanosoma (Herpatosoma) mariae, Mello, 1978 are presented. The experiments were carried out in Calomys callosus (Rodentia), reservoir of this parasite. The prepatent period varied from 6.6-10.5 days and the patent infection varied from 38-141 days. Amastigote forms in divisions were seen mainly among the cellular spaces of the spleen. Only trypomastigote forms were seen in the blood stream. Measurements of these forms showed that the total length varied with the course of the infection.

The prevalence of Trypanosoma catostomi in white sucker (Catostomus commersoni) from southern Ontario.

During the summer of 1975, 285 white suckers (Catostomus commersoni) from 10 localities in southern Ontario were examined for trypanosomes. Trypanosoma catostomi Daly and DeGiusti, 1971 was found in the blood of 11.6% of the fish examined using the haematocrit centrifugation technique. Infected juvenile fish (33%) and infected adult fish (4%) were found in 6 of 10 locations.

Studies on Trypanosoma (nannomonas) congolense. I. On the morphological appearance of the parasite in the mouse.

The pleomorphism of bloodstream Trypanosoma (Nannomonas) congolense was studied during the course of the first parasitaemic wave in mice using cloned and uncloned derivatives of three recent field isolates. The different morphological types were identified using the criteria described by Godfrey (1960). It was found that at any point of parasitaemia there were several morphological types of the parasite present, ranging from short to long forms. In the rising phase of parasitaemia, the short forms predominated, while at peak parasitaemia the parasites were highly pleomorphic, with significant proportions of short and "intermediate" forms although the long forms predominated. Pleomorphism was observed both in normal and in lethally irradiated (900 R) mice, even when the infection was initiated using a single organism. Such pleomorphism may result from physiological differences between the different forms of this parasite since these morphological types of T. congolense also differed in their ability to infect a new mammalian host.