How well did the animals work together? Why is that so?

Animals continue to work together throughout the novel, at moments building up real solidarity, such as when Boxer dies and is sent off.  Cats and rats do not get along, however, and at one point Mollie leaves because the others resent her bourgeois vanity. Significantly, Snowball is forced to leave by Napoleon because he disagrees with him. Following this, Napoleon makes Snowball the scapegoat for all the bad things that transpire on the far. They get along because they have subscribed to the idelogogy of "animalism," because they know the consequences of questioning (the dogs will attack them), and because they become so tired they do not have the energy to protest, because they cannot read or write and are easily persuaded by Squealer, and because they remain hungry as the story progresses, losing any energy for struggle.