Needs some work, but has potential!
As I base my scale from 1-10 in this off of the top flash submissions out there, anywhere from 5 to about 7 isn't a bad score. The animation isn't top of the line, but it isn't bad either. The only problem I really encountered with your drawing skills is the character movement, they basically just bounced around the screen. It's nothing you can't fix, you just have to add a little bit more detail to the characters when they're moving around the screen. Nothing you can't practice to help achieve higher schores!
You had around an 8 or so before I heard the music near the ending which was cracking a lot, so it kind of took away from your score in this department. Otherwise there were a couple of sounds that seemed a little off, but there was nothing too major to complain about here.
This was actually pretty funny, I got a laugh out of it since there were cows....and Santa was a cow, and then since you called it a "Cowgasmic" Christmas, even the name scored you some love in the Humor department.
The humor covered this for the most part, but cows during christmas was pretty damn funny, definitely unexpected. I also loved the mixture of Mortal Combat music with the Kill Bill type of vision when the cow heard something break.
Definitely a good flash, just needs a few problems picked up here and there, once you fix the character movements and details up a bit, and clean up the sound you have a great flash. It doesn't have to be spectacular to net a high score, but compared to today's top 50 in the portal, it has to be damn good in these categories, and you have the potential...so use it! Great flash though, very original!