Make Facebook give warning of distressing pictures of animal cruelty.

On many occasions i have logged onto Facebook only to be confronted by distressing and cruel pictures of animals being tortured or abused! I realise that the majority of people only post these images to raise awareness but once seen the image can never be erased from the mind, and the pictures i have seen have made me physically sick and unwilling to go onto Facebook! Please help me make Facebook give advance warning of potentially obscene or distressing images! Thankyou.