Islam, mercy and animals? Please extend your mercy to all animals.

My post to a Muslim:

The Islamic video starts with mentioning mercy.
Mercy.

So how can we practise mercy toward our fellow animals?
We know that animals want to live, they don't want to die. They love their family, if treated well, they love their life. They love their purpose on this planet..
If we kill them, we steal their family, we steal their life, we steal their purpose.
To have mercy over an animal is to respect his/her life, to say I respect you, I will let you fulfill your purpose in life.
We can never show mercy to a being by killing him/her.
So if the foundation-stone of Islam is mercy, then this should also be reflected in by treating animals as individuals, and not depriving them of their life and purpose.
 If we care about animals, and regard them as having a moral value: Only stopping using them and stealing their lives and products, is respecting them, their life and purpose.
I highly recommend this lecture: http://www.youtube.com/watch?v=oLgGnP0pWzM