从受试的草原雕血清中也未能检出FI抗体。用鼠疫EV菌经草原雕皮下注射感染，在其血清中能检出FI抗体，且至少可保持240天。
Pestis from its spit nor FI-antibody from its serum could be detected after the vulture had been fed with mice infected with EV strain .
草原雕