I know that it has been many moons since you first posted your message of inquiry and I want to at least get back to you on it. If you will type in the words cow fat into google or sbc yahoo, you will come up with a variety of websites on cow eating diet etc all of which will help you out. I really hope that you were able to solve this questions long before my answer, but I do care about helping you along and I hope that you are wll on your way with your project. If you are on a team your advisor should have pointed you onto these sites long ago. All the best.