The Rafeiro do Alentejo or Alentejo Mastiff, also called the Portuguese Mastiff, is a large breed of dog that originated in Portugal.The Rafeiro do Alentejo is of the livestock guardian dog type, and the name refers to its area of origin, Alentejo, in south-central Portugal.Although the word rafeiro means mongrel in Portuguese, the Rafeiro do Alentejo is recognized as a breed by the Portuguese ...