[Slings and Arrows]

http://www.dogbreedinfo.com/mastiff.htm

http://www.dogbreedinfo.com/bullmastiff.htm

English Mastiffs are much larger than Bull Mastiffs. IIRC, English Mastiffs take about 4 years to reach full growth, so the one you saw may well have been young.

[goat granny]

Thank you for the links, quite interesting...I can say without a doubt that the English Mastiff at the vets was a puppy. A BIG PUPPY...