My neopolitan mastiff used to run down the neighbors cats and catch them in his mouth. All you'd see is a head on one side of his mouth and 2 legs on the other He would walk them over to the porch and drop them and lick them all over in a loving manor. After awhile the cats started laying on my porch for a free bath.
Wendy, every mastiff breed I ever owned lived with a pug in the house or a cat in the area. I came to the conclusion that unless obviously animal aggressive, they are timid towards other non alpha animals. Every time I adopted a 130lb + dog, our pug came to play with it first. Only one of the 10+ I took him to see wanted to get him and that was a Bandogge(neo/ pitbull mix) trained to be aggressive obviously.
they are a very cool breed for sure, I am a mastiff lover now, glad I didn't have any back when I had money and rasied and showed my Rotties, Id of ahd a house full of all types of mastiff's too lol