London Underground sign: Dogs must be carried

It’s an oldie, but a goodie; the sign at the entrance to escalators on the tube, saying “Dogs must be carried”. Seldom do I see anyone carrying a dog, but I do see lots of dogless travellers using escalators. So, either most people are flouting the rule, or the sign is barking. Obviously it’s the latter. But what *should* the sign say,to convey its real meaning (if you are travelling with a dog, carry it on the escalator to prevent injury), ideally in fewer words?

• “Any dogs must be carried” – Maybe a little better – but it’s longer.
• “Carry your dog” – Not quite. What if your dog is at home, or you’re travelling with a dog that’s not yours?
• “Carry any dogs” – Better, but you should really only carry your own dog.
• “Dog? Carry it” – Almost – but any literate dogs reading the sign would be thoroughly confused!
• “Carry dogs” – Two words, active voice.  At least as good as the original.  Works for me.

Other suggestions welcome in the comments.

Update 23/7/2010: A timely article in today’s Metro about Batman – the reading greyhound. Also you can find lots more reading dogs here.