The Original Fila Brasileiro (OFB) or Old Brazilian Mastiff is a rare working farm dog breed from Brazil. The remaining Old Fila dogs preserved on farms in the interiors of Brazil are being gathered to become a formalized breed. The Original Fila Brasileiro is recognized by the SOBRACI in Brazil, and despite the similar name, it is a breed apart from the modern Fila Brasileiro. Two Original Fila Brasileiro working cattleThe temperament of the modern Fila Brasileiro dog has become a controversial topic. The breeders of the modern dogs are proud of their 'ojeriza' (extreme aversion to strangers) and are totally averse to the use of guard dog training. However some canine behavior experts have recently been demonstrating their opinion of what they consider to be the true temperament of modern dogs by classifying them as fearful dogs. According to Jairo Teixeira, a very influential dog trainer in Brazil, and some other dog trainers, the 'ojeriza' of modern dogs is a synonym of fear.