Last night, I had a vivid dream that I remember very well....
I was at my parent's house, in the back yard. There was an area fenced in with pigs, some full grown and some babies, a small pedigree dog with a red bow around it's neck, a wolf and a white bear. All those were behind the fence. Outside the fence, there was a baby pig that was walking away from the back yard. I started walking to it, then noticed the mama pig coming to the baby. I turned around to see if the gate was open, but it wasn't. I noticed the other animals were close to the front of the fence, looking out towards me. The wolf was walking towards the animals, like it was going to attack. The white bear was right behind. The wolf got close to the gate and took a swipe at one of the pigs. I grabbed a shovel and started beating on the fence at the wolf. My dad shows up about that time and I yelled at him to get his shotgun. The wolf started getting close to the gate, as if it was trying to get to me. The bear was directly behind it. I hit the fence again, and got the wolf on the forehead, stunning it. That's when I woke up.

What the heck does this mean? and why is it sticking in my head so vividly?

AyeCantSeeYou but I will try to interpret the dream as best I can.

From where I sit it looks like you are witnessing some external threat approaching.  I would say it was some sort of domestic / family issue considering the domesticated family of livestock.  The approaching wolf sounds to me like a person you see as a threat to the well being of possibly your family life, or you personally in that role.  The white bear behind the wolf I would think is another character egging on (behind) this threat.  It sounds like you are trying to fend off this threat.

The pedigree dog with the red bow is likely another character linked to the drama but not playing a major role, but figuring out a group of people linked to those three 'characters' may give you an idea of what this is all about if you don't know already.

It may be vivid because you are not acting on this situation when you should be banging on the fence to scare off the threat?  Does that make sense to any drama going on in your life at the time?