There are plenty of theories out there regarding cattle mutilation. I have heard the Government, Aliens, Skinwalkers, Bigfoot, Satanic Cultists, mean kids, and even natural predators mentioned.
I would like to add another possibility to the list.
While many people have suggested that they thought it was a US government cover-up (for those mutilations occurring exclusively in the USA) the fact remains that this is an international problem.
I would like to put forwards a disturbing alternative. It relates to the possibility of Alzheimers disease being transmitted by a prion:
https://www.nature.com/news/the-red-hot-debate-about-transmissible-alzheimer-s-1.19554
I am not going to make claims about Aliens, not about a government conspiracy, but instead discuss the possibility that Cattle Mutilations are actually a "corporate externality".
Now prions were discovered in the 1960s:
https://en.wikipedia.org/wiki/Prion
To date we simply don't know how much prions affect the world. The assumption is that most prions are harmless except for the one that causes Creutzfeld Jacob Disease. The truth of the matter is that there may well be many diseases with unknown causes that are actually the result of prions. Prions are hard to detect and often behave much like viruses, causing people to assume they are dealing with a virus based disease, when, perhaps not?
Now suppose there is a large organization that has at some point made it their business to properly investigate prions, and have found out that they are far more problematic and widespread than current science suggests. Of course that is a big
IF. Consider the possibility that such an organization suffers from exposure to legal and financial blow-back from the discovery of prions that they have been releasing as part of their commercial activities. Assuming that the company in question can afford military hardware like silent blackhawk helicopters and special-ops teams, the question would then become, why do this study covertly and not simply buy single animals from various locations, perhaps having the identity of the study concealed via holding companies (the same question might be leveled at most of the conspiracies on the list though). Is this a way of conducting covert mission training exercises while also gathering scientific data, "mutilating two cows with one stone" perhaps?
The reason I have raised this is that the checklist for the cattle mutilations seems consistent with the organs and blood taken in testing for Creutzfeld Jacob Disease.
Now, am I seriously suggesting that Monsanto is behind Cattle Mutilations? No. I'm just having a guess.