Experimental transmission of Babesia major by Haemaphysalis punctata.

Using a newly isolated strain of Babesia major and a clean strain of laboratory reared Haemaphysalis punctata it was shown that adult female ticks could be alimentarily infected by feeding on infected calves but that larvae and nymphae could not. All stages were able to transmit the parasite. Two syringe passages of B major resulted in a complete loss of infectivity to ticks.