Some observations on the isolation andin vitroculture of two mammalian trypanosomes,Trypanosoma theileriLaveran, 1902, andT. melophagiumFlu, 1908, with special reference toT. theileri

Transmission of Trypanosoma theileri to cattle by Tabanidae

Tabanids were collected in an area in northern Germany, where pastured cattle were abundant. Trypanosomatidae were identified in 14% of tabanids examined. Twelve cattle became infected with Trypanosoma theileri after applying usually 2-5 infected tabanids, to the intact oral mucosa. Haematopota pluvialis, Haematopota italica, Hybomitra micans and Tabanus bromius were identified as vectors. Infective stages of Trypanosoma theileri were identified in the gut and in the faeces of tabanids by transmission experiments. The minimum prepatent period was less than 4 days. No apparent signs of disease were observed in the infected cattle.

Comparative studies of Trypanosoma vespertilionis Battaglia and Trypanosoma dionisii Bettencourt & França

In diphasic blood agar media Trypanosoma vespertilionis developed spheroid clusters as compared to rather long, sausage-shaped (sometimes branched) clusters formed by Trypanosoma dionisii. The former species attained a greater population density (approximately 6 X 10(7) organisms/ml) than the latter (approximately 2 X 10(7) organisms/ml). Greater numbers of epimastigotes, some in active binary divisions, were observed during the logarithmic phase of growth, and morphologic changes occurred during cultivation which correlated with increased acidity and a depletion of glucose. Maximum numbers of trypomastigote forms were found during the stationary and early death phases. Most of the forms observed after 20 days were sphaeromastigotes. Glucose concentrations decreased to 0 M in T. vespertilionis and to 4.4 X 10(-5) M in T. dionisii cultures during the stationary and death phases. By the 12th day of incubation cultures of T. vespertilionis were more acid (pH 5.5) than those of T. dionisii vespertilionis and T. dionisii contained common and specific antigens. At least 2-3 common antigens were detected in extracts reacted against heterologous antisera. Specific antigens were observed as nonidentical lines formed by extracts reacted against homologous and heterologous antisera and with antisera absorbed with heterologous antigens. At least 2 specific antigens were evident in extracts of T. vespertilionis and 1 in extracts of T. dionisii.