Bismillahir Rahmanir Rahim.
Three. According to our Hanafi Madhhab, the dog's body is not impure. So if a dog touches someone's body or clothes, it will not become impure. But dog saliva is impure. If a dog pulls someone's clothes with its mouth, if the saliva gets on the clothes, then the clothes will become impure; Otherwise it will not be impure. (Al-Bahrur Rayeeq: 1/101; Fatwaate Hindiya: 1/48; Addurrul Mukhtar: 1/208)
Four. Eating dog meat is forbidden in all religions including Islam.
Five. Killing of hunting dogs, guard dogs is unanimously haram or illegal. Killing mad dogs, troublesome dogs is lawful according to all scholars. Killing dogs in normal condition is unacceptable in the eyes of Islam. (Source: Kuwait-based Islamic encyclopedia Al-Mawsuat al-Fiqhiya al-Quatiyyah: B. 35, p. 132-133)
Six. If possible, feeding the dog, giving it water, and rescuing the dog if it falls somewhere are acts of reward in the eyes of Islam. A pure hadith declares that an adulterous woman will also be granted Paradise for feeding a dog with water. Rasulullah (SAW) said, 'Once a thirsty dog was wandering near the well. He was dying of thirst. Suddenly an adulterous woman from Bani Israel saw it. He took off his socks and gave the dog water. Because of this, his past sins are forgiven.' (Bukhari: 3467)


