If it's show time ill post a Boerboel picture. It's a very largeMolloser (170 LBS when lean) and they indeed don't warn you when they bite. You can try the dominance game but be prepared to get into a fight with the dog.
I only had to use force on my Boerboel once, it's a dog i resqued from death by adopting it.
She confronted my authority after beeing 2 weeks in our house. She stood ground, i stood ground, i was able to grab my sjambok and gave her a few hit's with it while growling at her.
After that she decided i was the Alpha male in the herd and her days of leading the pac was over she calmed down.
My children ride horse on her back, but woe he who dares to enter my property without prior concent from the owner.

This is a picture of one of her family members