"Our boy needs a retirement home," the shelter posted. "... he is so depressed, we want him to get into a permanent home. Would you please help us find Jack a home where he can rest peacefully and find all the love he has missed?"
There's some happy news for Jack though - the shelter told The Dodo that, thanks to the attention on Facebook, they've already gotten a "couple dozen" applications for his adoption. He may be well on his way to a forever home.
There are lots of other senior dogs just like him who still need homes, though - if you're ready to add a dog like Jack to your family, visit your local shelter or search on Adopt-a-Pet.com.