Well that is good to know. I sure have a long way to go before I start taking pictures that have the quality of what they produce. I haven't bought the camera yet but Isn't the 20D an older model. I think that they are up to 50D now and it looks like it can store pictures at 15 megapixels. How many megapixels are needed for photographing cattle? I don't think that you would need 15 megapixels for the size of pictures that you commonly see.
Nikon has a 40D, 50D, 60D, 70D, 200D, 300D (BRAND NEW), and 700D. They also have even higher range series for serious pro photographers. You dont, by any means need a 15megapixel camera. I feel that megapixels are an overrated thing, and manufacturers use them to hype up cameras. I shoot pro with a 10 megapixel camera and do quite well obviously! Just be sure your camera is set at the largest file size. Where you will really get messed up is when you shoot at a really small file size. Large is somewhere in the vicinity of 2500 x 3800 pixels. Stay with this size and you will be grand!!
I dont think you need to spend tons on photo gear. Your basic DSLR (digital single lense reflex) camera will be all you need. Spend money on good lenses, and you will have that camera for several, several years! Keep your aperature (f/stop) number relatively low (below 5) and it will blur the background itself. It focuses on the animal itself, and everything else is blurred. Especially things farther off in the background. If you want to have the background in focus, go with a higher setting, such as f/12-f/14 or higher. Keep your shutter speed at 300 or higher, and your ISO at 400 or lower. The higher your ISO, the grainier the photos get.
Wow, thanks for the info! Like I said, I am really just a beginner so all of this info helps out a ton! Thank you for adding this informative post!