Great thread, truly a find, and I can see that you guys know what you are talking about.
I am Portuguese and I would like to add something to the mix.
When the portuguese had slave colonies in brazil, in mid 1700's all the way to late 1880's, they needed dogs to control the population, hunting and slave capture.
The dogs weren't big, but they were ferocious and able to take not only a man but also to accompany hunters and protect the homestead. Those where the first filas. Fila come from the verb filar, which is to catch, grasp or clutch.
The job of the fila was to catch and old, be it large game or people.
Now one of the three types of dogs that were shipped to Brazil by the landowners where Castros Laboreiros, Serras da Estrela and Portuguese Pointers.
Serras are large dogs, lanky and furry, but we also have them with short hair. Castros are ferocious guards, brindle to fawn. Portuguese pointers and Podengos are used on boar hunting. Mix the lot and you get a Fila.
When slavery was abolished in brazil, early 1900's the ranchers started to deal with Cattle, and the innate characteristics of the Fila predecessors to deal with Cattle and guard the homestead came to the fore. Prey drive is taken out, these are dogs that must live on a farm and able to not kill the chickens and other dogs, attach to the family and keep intruders at bay.
Nowadays the Filas are being mixed with other breeds to melow some traits, but one should keep to the what the breed is used for.
Black filas are not that wanted, they would overheat. Fawn are preferable, but sometimes you see light brindle on the farms. The farmers couldn't care less for the color but natural selection sorted that out.
Hope that helps.
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