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Great Danes are VERY tall dogs compared to American Bulldogs. The 6month old Great Dane will be about the size an average American Bulldog will get. American Bulldogs will not have cropped ears even when being show dogs. Most importantly the heaviest an adult AB will get is to be 130lbs while the GD will be 150 when still a puppy.
If he looks like this dog.
English Mastiff
The American Bulldog breed was not developed until the 1980's however, the dog breed in which they descended from was the Olde English Bulldogge. The Olde English Bulldogge ( dating back to the 1700-1800's) looked extremely similar to the American Bulldog only it had more English Bulldog characteristics (like a shorter snout) than the American Bulldog.
Iwao Takamoto created Scooby Doo to look like a Great Dane .
There is unfortunately no webkinz great Dane......
Some types of Great Dane have spots, making them appear like oversized Dalmatians. An example is the Harlequin Great Dane.
We have a Great Dane and a Golden Retriever. They love to play and run in the yard. They "body slam" when they play like football players in the field.
Maybe a trip to the vet is called for?
I never seen or heard a mix like that. Google french buldog, see what they look like and come to a conclution.
No, they are not the same. the American bulldog, like the English and french bulldog, is from the bulldog family. the American pittbull terrier is from the terrier family like the jack Russel.
Great Danes have very thin coats, so they do not like cold weather. If it's comfortable for a person, it's comfortable for a Great Dane. In cold weather they really do need a coat to help them keep warm, just like a person.