1.. In order  for the slaughtered animal to be halal, it should be cut in the right place, so the two veins should be cut, along with the trachea – which is the windpipe – or the oesophagus – which is the food pipe – ; or one of the veins should be cut along with the trachea and oesophagus. 2. If three out of the four were cut, then the bird you slaughtered was halal, and it does not matter if the blood that came out was a small amount, or the bird did not move after it was slaughtered. But if you did not cut anything except one vein only, then it was not halal. 3. It is disliked to slaughter an animal with a blunt instrument, because that causes unnecessary suffering to the animal. The one who does that must seek Allah’s forgiveness for slaughtering this bird with the blunt knife, and not do such a thing again.

If the animal has been slaughtered properly, then it is permissible to use its horn. If the animal is still alive or it dies without being slaughtered in the prescribed manner, then there is a difference of scholarly opinion as to whether it is pure or not. For more, see the detailed answer.

Summary: meat slaughtered by one who is uncircumcised is lawful and may be eaten, whether he is a Muslim or a kitaabi (Christian or Jewish).