Ok, couple things. As an avid hunter I can assure you that unless the 'cow' was shot, a hunk of meat hacked off and handed over within minutes, it is not due to 'freshness'.
as a foodie, I know that most beef is hung for several days to months to cure.
So if I had to guess, this wiggling is either due to hoax, which is what I think it is OR it's full of maggots or bugs of some sort like in Poltergeist as Daniel suggests.

Its an upholstery hammer, you just screw on your desired length handle. The switch in the middle is for making it a right or left handed hammer.

There's no place like 127.0.0.1. XL