Venus was our Great Dane that we adopted from the Milo Foundation on Valentine's Day in 2007 when she was 8 years old.
She passed in April 2011 in the most peaceful and graceful way. She was 12 . Great Danes only live to be 8 on average, so my wife Carla likes to say "she lived 150%".
Venus had been slowly declining from arthritis, dementia, and general old age stuff. When our vet came to the house to put her down, she didn't even seem to feel the needle. (Her back legs had gotten numb, which was part of her problem with walking). She went straight to sleep right in her bed, just as she would at night time.