Kocan K M, Hair J A, Ewing S A, Stratton L G
Am J Vet Res. 1981 Jan;42(1):15-8.
Cattle were inoculated with a Virginia isolate of Anaplasma marginale Theiler and served as an infective source for laboratory-reared Dermacentor andersoni Stiles and D variabilis (Say) nymphs. Following a molt and subsequent feeding of adult ticks on susceptible cows, transstadial transmission of A marginale occurred from cattle with parasitemias ranging from undetectable (in a carrier cow) to a peak of 27% (in an acutely ill cow). Homogenates of gut tissue from unfed, incubated, and feeding adult ticks that were infected as nymphs were all infective; however, the prepatent period varied according to treatment of ticks after they had molted to the adult stage. Prepatent periods of infections in calves resulting from injection of homogenated tissue from unfed adult ticks was 29 and 34 days longer than the prepatent periods that developed in calves exposed to homogenated tissue from ticks that were feeding or incubated at 37 C for 3 days. Transovarial transmission did not occur when F1 larvae, hatched from eggs produced by female ticks known to be infective, fed on susceptible cattle.
用弗吉尼亚州的边缘无形体泰勒分离株接种牛，这些牛作为实验室饲养的安氏革蜱和变异革蜱若虫的感染源。若虫蜕皮后，成年蜱叮咬易感母牛，边缘无形体在牛之间发生经变态期传播，牛的寄生虫血症范围从检测不到（带菌母牛）到峰值27%（急性病母牛）。作为若虫时被感染的未进食、已孵化和正在进食的成年蜱的肠道组织匀浆均具有感染性；然而，潜伏期根据蜱蜕变为成年期后的处理方式而有所不同。注射未进食成年蜱匀浆组织导致小牛感染的潜伏期比暴露于在37℃下进食或孵化3天的蜱的匀浆组织的小牛的潜伏期长29天和34天。当已知具有感染性的雌蜱所产的卵孵化出的F1幼虫叮咬易感牛时，未发生经卵传递。
