Mercy in slaughtering

Non-muslims think that slaughtering is unkind and that Sacrificing Feast is an opportunity for excruciation animals and that it opposites Mercy of Islam..but in fact it's very merciful from more than one side..
At the first butcher must be adult and make his knife very sharp to cut the nerves quickly and not to make pains for the animal and he must slaughter very quickly,also he must hide his knife and try not to let the animal see it,and if he is going to slaughter more than one animal he must do all his best to slaughter the first in a place and the other in another place lest the other may see it,and if blood blotched his clothes he must change this clothes or remove this blood that it may see it and become afraid,and he must say obviously:"Bism ALLAH,ALLAH akbar ",and he must cut two vessels reach to the brain,trachea and esophagus,and after cutting them he must wait till the bleeding stop to make sure that there is no blood in the body;as eating blood is forbidden in Islam..
On the other side Science proves that eating blood is harmful as it is considered as a very good environment for germs and after boiling it's still harmful as some of germs don't affect by boiling..and in other ways of killing animals like electricity and guns they aren't kind,cause pains for animal and don't make the blood go outside the body.

These rules show that Islam is a great religion,and that Islam cares for Animal Rights before west cared for it.