Bullmastiff

The Bullmastiff dog breed was developed for protecting hunting grounds against poachers in England during the late 1800s by crossing Bulldogs with Mastiffs.

The resulting cross gave gamekeepers a fast and power dog that could ambush poachers with hunting dogs and simply overpower them. They were trained to take down intruders without mauling them to death so that they could be punished appropriately by the property owner.
The Bullmastiff was so effective at its job that it became a favorite guardian of estates throughout England. Repeated Bulldog and Mastiff crosses would yieled a viable Bullmastiff population that could now sustain being bred as a bloodline rather than continuing the cross breeding. The AKC would officially recognize the breed in 1933.   

• Temperament

Bullmastiffs will protect their family to the death against intruders when provoked, but are typically easygoing gentle giants when not under attack. They can do well with children, but it is preferable that the children had a hand in raising them from puppies.
They are sometimes aggressive with other dogs, especially males, but do get along just fine with other pets like cats for example. These dogs are powerful, and very stubborn. It can be difficult to coax them into doing anything that wasn't their idea in the first place.

                             

• Health                                                                                                                                                     The Bullmastiff has very little tolerance of heat and humidity and should be considered an inside dog and guardian of the household. If drool makes you feel a bit nauseous, then this definitely is not the dog for you. If you are a light sleeper then you may not be very fond of the snoring either! Exercise requirements are fairly insignificant and can be met by a daily walk around the park or neighborhood. Be sure to have ample space available for him to lay down and stretch on comfortable bedding.
  The most threatening health conditions for this breed include gastric torsion, elbow dysplasia, and canine hip dysplasia. Entropion can also be of concern, but is not as prevalent as the prior conditions.
  A Bullmastiff's life span is approximately 8-10 years on average.