If I travel by commercial airliner, I only take folding knives with me, because they have to be packed in my checked baggage, and they do not have shapes that are as obvious to baggage handlers who might feel they need my knife more than I do. Folders do an excellent job of cutting up animals and are very easy to carry around. I normally have 3 folding knives on my person every day and have carried a folder on a daily basis for almost my entire life. With all the regulations and metal detectors around today, I sometimes have to leave my knives at home or in my car and always have to pack them in my checked baggage when traveling by airline.
One time in Africa, my son had just shot a cape buffalo. My professional hunter looked for his knife and realized he had left it back at camp. He asked the trackers if any of them had a knife, and they didn't. He then asked my son and me if either of us had a knife. I pulled a little $20 Gerber folding knife with plastic handle out of my pocket and the trackers proceeded to cut open up the buffalo, take out all its internal organs, cut the buffalo in half around the middle so we could load it in the truck, and then make biltong out of the buffalo's heart. When they handed the knife back to me it was covered with tallow, dirt and blood and was getting pretty dull from cutting through inch thick hide and other tissue. I had to scrape off all the gunk and then clean the knife up really well in hot water and soap when we got back to camp. That's the day I learned how effective even a cheap little pocket knife was on big, tough animals. I will say that my little Gerber would have failed miserably if it had been an elephant rather than a buffalo that we were trying to cut up.
I have used a folding knife a lot for cutting up game animals, but they are not as comfortable or strong as a good fixed blade knife and are much harder to clean up. Because I always carry a folder in my pocket and sweat on it a lot, I prefer stainless steel for the blades. I have been especially happy with S30V knives I have been using the last few years and find the Lone Wolf Harsey T1 plain blade to be my favorite for hunting and daily carry.
Given my choice, I would always prefer to use a fixed blade knife to cut up an animal. I agree with the people posting above who say shorter blade knives are better to use. I like blades from 2 1/2 inches to 4 inches long, with a 5 inch blade being as long as I want to carry with me in the field. Longer knives have their place when butchering the meat for packaging, but they are not so good when you are working on the body of the animal. Something along the lines of Ron LaClair's Skinner knife is hard to beat.
Allan