A.环杓侧肌B.环杓背肌C.甲杓肌D.杓横肌
A.20%in dogs,30%in cats 犬20%,猫30%B.30%in dogs,40%in cats 犬30%,猫40%C.40%in dogs,20%in cats 犬40%,猫20%D.50%in dogs,30%in cats 犬50%,猫30%
A.6-----12B.12----24C.24----48D.26----72