In the book Animal Farm, written by George Orwell, animalism refers to communism. This literary technique is called symbolism, which is the use of persons, places, things, objects, to represent an idea that is better explained by using these symbols. Writers use this technique to make their story more appealing to the reader.
In Animal Farm there were lots of other symbols used for every day life. The animals represented society and their stereotypes and in a broader sense the workings of the communism.