The Brazilian Terrier, or Fox Paulistano
The Fila Brasileiro or Brazilian Mastiff
The Fila Brasileiro is another animal entirely, large (about 50 Kg) and very powerful. They were bred as working dogs on plantations or cattle ranches, probably from a combination of Mastiffs, Bulldogs and Bloodhounds, but unlike some large breeds they are normally alert and active.
Although affectionate to their owners and families, it goes without saying that Filas are utterly and completely unsuited to be apartment dogs! Infact, in many countries such as the UK, Denmark and New Zealand you cannot own one at all. In the past Filas were often trained to be "Ojeriza" or distrustful of strangers, and with their very strong protective instinct this made them sometimes dangerous to anyone outside of their "pack". But this was the fault of stupid owners rather than the dogs themselves, and with proper training and socialisation from an early age they are calm and safe with strangers, even if not especially friendly.
Filas still make good farm dogs, and they might be branching out. They are reportedly used by the Israeli army and some American police forces, where they have the advantage as tracker dogs that, if necessary, they are fiercely defensive of their handlers once the quarry is found.
A five year study by the Brazilian army compared Filas, Dobermans and Alsatians in jungle conditions, looking at intelligence, aggressiveness, sensibility, temperament, energy, resistance, and strength. The Alsatians were smarter, the Dobermans more aggressive, but Filas won every other category.