The main characters in Animal Farm to which we can equate characters from Lord of the Flies, would be Napoleon and Snowball who compare to Jack and Ralph respectively. Squealer relates to Piggy and the dogs compare to Roger. Boxer relates to Simon.
Whilst stating that the characters are or may be similar, we must remember that Lord of the Flies is about boys who do not have any measure of experience whereas the animals suffer due more to ignorance and lack of education.
Napoleon is similar to Jack as he is the ultimate embodiment of corrupt power. Napoleon ensured that the animals would
salute the flag, sing “Beast of England,” and receive their orders.
Jack, determined to become 'chief' and forcefully making it happen
can no longer recognize a moral code.
Both Napolean and Jack will stop at nothing to achieve their ultimate goal of being in charge.
Snowball would be most similar to Ralph as they both have the welfare of all the animals / boys at the centre of their actions
Snowball organizes commitees and rallies the animals in the
defence of the farm against the humans
Ralph (under the guidance of Piggy) sets up the conch as a means of democratic communication. He understands the importance of protecting themselves and sets about building shelters and so on.
In compring Squealer and Piggy, the similarities end with the fact that they are both the 'second-in-command' to Napolean and Ralph respectively. Their roles are extremely important and they contribute to the progression of the plot but obviously they flfill very different roles.
Boxer is likened to Simon because they fulfill a more abstract role than the others and are symbols of a greater good. They do not really have any similar characterisitics. Both Boxer and Simon live in a world detached from the rest.
Finally the dogs compare to Roger and represent the brutality that exists in the world.
Refer to the eNotes study guides for examples that show the true nature of some of these characters.