“And eat not of that where on ALLAH’s name has not been mentioned for verily it is abomination.(Qur’an /6 : 121)
The animal has to be lawful (Halal) to eat, alive, healthy, to be slaughtered only for the reason of food, in the name of God and not for any other reasons (it has to be well-fed, not thirsty handled and moved gently and individually). The sacrifice must be made upon saying the name of God and in proper Islamic way. The animals if they are ill or injured should not be sacrificed. The person who makes the sacrifice must be believers or from the people of the book. The animal has to be slaughtered with a sharp object (knife) and in a fast way so that the pain of slaughter is minimised. Islamic way of slaughtering is less painful and is much better scientifically. The main purpose of Islamic way is to let the blood flow out, since blood is considered impure. Blood is a good media of germs, bacteria, toxins etc.
Therefore the Muslim way of slaughtering is more hygienic as most of the blood containing germs, bacteria, toxins, etc. that are the cause of several diseases are eliminated. Also, the Islamic way of sacrificing is very less painful to the animal. The ‘slaughtering’ is to be done by cutting the throat, windpipe and the blood vessels in the neck causing the animal’s death without cutting the spinal cord.The main artery which supplies blood to brain is cut with a swift clean stroke, so, the brain dies in just about 2-3 seconds, and thus the animal doesn’t feels pain after that. The twitching is just an response of the nerves and spine, which doesn’t constitute pain. Meat slaughtered by Islamic way remains fresh for a longer time due to deficiency of blood in the meat as compared to other methods of slaughtering.