.. I felt that chicken smoothie was lacking in cows so here you go! 
There's 3 different types of eyes because I wasn't sure how to do them, ones a bit scary like haha, lock alpha colour .. Please don't remove my signature and all that stuff.. You may edit the lines a bit if you want , like give it a better body because it's a bit naff..
Edit: There it's slightly less fat now XD
.. It should do 
click on colour me in , then go to the colour layer, click lock alpha, then you can colour the cow too