Animal abuse?

Desmond from Dinsdale

What is defined as animal abuse? Today at work in Woodward street a dog could be heard barking for a while. I went through the nearby yard and had a look over the fence at 14 Woodward street, a fairly new company since the property changed hands. There was a dog tied up and a [darkish] person taunting it. The dog was at the end of the rope and was snarling by this time as the person rhythmically stepped forward and kicked its rear end, not very hard but a push that overbalanced the animal a few times as they kept just out of reach of its jaws. The dog was really angry and snarling - I called out to them "Hey, what are you doing to that dog". They sneered back at me and said "I'm just playing with him, I've got to play with him now and then" and walked inside. My interpretation of that was "He is a machine for protecting our property and we want to make him vicious by regularly teasing him". So the question is , what can be done about it if anything? Does there have to be evidence of some form of abuse?
Edit: The actual address is at 14 Woodward street for those who didn't understand the initial statement. I've also changed the description to "person" as I was obviously confused about the gender because on the day they were wearing coveralls.