Infection involving any organ system (either overt, or indicated by increased body temperature or WBC parameters), which fails to respond to antibiotic therapy within an appropriate period of time and is accompanied by systemic signs of illness.

• 无论是明显可知或因体温升高白血球数目增加而判断为感染所致，且在抗生素治疗无效并伴随动物全身性不适症状出现时。