Well...Incase you missed my sarcasm, I call upon Occams Razor for the third time in two days.

First Solution: Thousands of farmers around the world have the technology, knowledge, and expertise in atomical surgery. They often mutilate their own cattle, file police reports, for unknown reasons.

Second Solution: An outside source has been doing this.

I believe it's aliens, because noone on planet earth has the technology to do it with the precision it's done with.

Incase you don't know, all of the mutilations are done with cell-level percision. This is why I keep on saying Atomical surgery. This is all on a very very very small scale, and would require technology that is not available on earth.

Cell-level surgery does not exist on earth. Thus it solution two.