an australian expression derived from "hair of the dog that bit you," "get a dog up ya" is a jovial instruction to take your acoholic beverage and drink it, similar to cheers.
"Thats a shame. Why don't you get a dog up ya? Its bound to set you straight."
"Lets both get some dogs up us."
Drunk Aussie Yobbo B: yeah this is fucked
Drunk Aussie Yobbo A (Yelled out in the crowd): Come on bombers, GET A DOG UP YA!!