英语语法分析

The author observed the clinical symptoms carefully and found out that the typical symptom was introflexion of chicken's claws. On the basis of this symptom the early diagnosis can be made.

作者对雏鸡维生素b_2缺乏的临床症状进行了较为详细地观察，典型症状是趾爪向内弯曲，以此可早期做出诊断。