2.7.2 Pathogenicity in mice
Groups of five 6-week-old female BALB/c mice (Yangzhou Experimental Animal Center, Jiangsu, China) were anaesthetized with pentobarbital sodium and intranasally (i.n.) inoculated with 106.5 egg infectious dose (EID50) of H7N9 AIV isolates in a volume of 50 μl. Body weight changes and mortality of the infected mice were monitored daily for 14 days. Mice were humanely euthanized if weight loss was over 25% of their initial weight and scored as dead for humane reasons.