What would have happened if some, or if any, of the animals would have dissented at any point of the story Animal Farm?
For it to matter, it would had to have happened early in the story and it would have to have been done by many animals.
If you think about it, some of the animals do dissent. Snowball dissents by pushing for the windmill. The hens dissent by smashing their eggs. But by the time these animals dissent, it's too late. By the time they dissent, Napoleon already has his dogs and he has the support of most of the animals. So by then he's pretty much invincible.
For their dissent to have made any difference, more animals would have had to do it much earlier in the story. If they had, Napoleon could have been overthrown. Of course, if they had, Jones might well have come back.
In a sense, maybe the animals were doomed. If they rebelled early, the went back to having Jones. If they didn't, Napoleon gained power and they could no longer dissent.
Napoleon's organization of the social and political machinery helps to crush dissent. The idea behind Napoleon's power is to ensure that there is an institutional "wall" that precludes any dissent. The ability to organize a governmental approach that disseminates information to consolidate power directly eliminates the prospect of dissent. As the animals do dissent, their actions do not impact Napoleon's power and control, withering the effectiveness of their disagreement with the political and social order. In this light, Orwell seems to be pointing out that the true terror of governments like Napoleon's is not their approach to dissent, but rather how it impacts freedom so that individuals no longer feel the effective need to use it.