Michael Sullivan, of the Ryria Chronicles, talked about this in the past. He said he had no desire to make up new basic animals, words for things (like miles for distance), new method for counting time, etc in order to create a unique world. He said that type of thing just clutters up a book for no reason. Stick with basic things that everyone can relate to and it wastes no pages and causes no confusion. Obviously you need to create some unique elements to make your world memorable. But I believe Sullivan was saying save that stuff for things that are cool and not the name of the temperature gauge or a new name for a horse like animal. I agree with that.