Why would an alien who evidently does not wish to be discovered leave an animal carcass (it has mutilated) around to be found?
Why would an alien take time to preform some weird operation on an animal(out in the open) when it would be simpler and less open to discovery to do it on-board its ship?
If they are so interested in studying cattle why don't they just swipe a few and breed their own?
Why do aliens have such a fixation with anal probing humans?
Why is Al Franken such a turd?
Why are there no answers to the questions that truly matter???? WHY!!!!!!!!!!!!!!!!!!!!!!!!!
Maybe they want to open up a Ruth Chris Steakhouse and are just practicing. It's either that or they are bovine necrophiliacs. Or they are so stupe that they believe because cows put out so much methane that they believe the cows are the intelligent life. But we know one thing for sure it is quite obvious that the aliens are not Hindus.
There are answers to such questions. They may not meet your criteria in the near term.
1) A lot, perhaps all, of the mutilations appear to take place aboard craft hovering or even that abduct the cattle, fly off, return to the spot or near the spot and drop the cow--usually for significant height.
2) You've not begun to explain the KNOWN factors that are COMMON in EVERY valid mutilation case. You haven't BEGUN to do that--do that and THEN ask the questions that remain unanswered.
3) Some contend that it's American Government JOINT research with ET's studying pollution and/or nuclear pollution. Others contend that those specific organs and blood products are needed in ET food/breeding/DNA enhancing . . . . whatever . . . experiments/projects.
The degree and attitude of skepticism you voice regarding the cattle mutilations just indicates to me--increasingly--that you have NOT studied the phenomena deeper than a slight surface scratch--comparatively.
Sigh.