The initial stage of infection with cyclically-transmitted Trypanosoma congolense in rabbits, calves and sheep

摘要: Abstract Glossina morsitans infected with a stock of Trypanosoma congolense were used to infect rabbits, calves and sheep. Local skin reactions developing after 6 10 days at the sites tsetse bites removed surgically or post mortem, tissues processed examined for trypanosome distribution pathological change by light, electron fluorescence microscopy. from rabbits intervals between 7 19 infection 8 30 infection. A single reaction sheep was Observations also made on presence trypanosomes in lymph nodes blood animals. Substantial numbers located collagen deep dermis near bases hair follicles following all three host species. The parasites numerous 12 calf most heavily infected. Trypanosomes seen lymphatic vessels superficial draining local up day 10. Although many destroyed extracellular lysis, few detectable dermal until calves. multiplication development each accompanied focal disorganization degeneration areas collagen. Reactions 15 showed acute inflammatory exudative changes extensive mononuclear cell infiltration particularly showing necrosis vicinity vessels. Macroscopically, left situ gradually disappeared about 16 21 Histological examinations confirmed that subsided 14 21, leaving newly formed persistent perivascular tissue foci cells.