Does touching a leash that was used for a dog invalidate ablution (wudu')? And must prayers performed after touching it be repeated? And how is the leash purified?

If the worshipper believes that the aforementioned leash belonged to a dog, it is not permissible to touch it or carry it during prayer, because it is highly probable that it has been defiled by the dog (saliva, sweat, hair). The preponderant opinion is that a dog is impure in all its parts. Therefore, whoever prays with something to which a dog's impurity has clung, their prayer is invalid if they knew about it at the time of prayer or became aware of it during prayer. However, if they prayed with it forgetfully or in ignorance of its impurity, their past prayers are valid, and ablution is not nullified by touching impurity.