Does removing a portion of live skin from the foot, along with dead skin, invalidate ablution (wudu')?

Ablution is not invalidated by cutting off part of the hand or foot, or by trimming nails, or by shaving the head. This is because whoever performs ablution and then does any of these things remains in a state of ablution. It is not necessary for him to wash what is beneath the trimmed part of the nail, or to wipe the place where the hair was shaved. The people of knowledge have explicitly stated this.