The Neapolitan Mastiff is one of the largest, ancient dog breeds. They were developed as family and guard dogs in Southern Italy. The largest of them could weigh up to 120 pounds and stand more than two feet above the ground up to the shoulders. They mainly became famous by being featured in the movie Harry Potter.
Also, this breed almost became extinct during World War II but thanks to the efforts of an Italian painter who mixed them with an English Mastiff, they were able to survive.
The Neapolitan Mastiff is aggressive and can sometimes be very overprotective of their owner's families which they belong to. No need to worry though, he would do no harm against his master's new born child. They make good pets but need to be socialized from a very young age to reduce their aggressive trait.
These dogs have a scary appearance and a deep bark, both of which are usually more than enough to frighten people with bad intentions.
Neapolitan Mastiffs have several of what some might consider gross habits: slobbering, drooling, wheezing, grunting, snorting, and notorious for passing gas.
Sources: http://dogtime.com/dog-breeds/neapolitan-mastiff#/slide/1
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