In Animal Farm, how do the owners of Foxwood and Pinchfield react after the rebellion?

It must be noted, firstly, that Frederick of Pinchfield farm and Pilkington of Foxwood, were sworn enemies and could not tolerate one another. They both had, however, a similar response to the Rebellion. Both were 'thoroughly frightened' by what had happened on Manor farm and wanted to prevent a similar event from happening on their farms at all costs. They initially mocked the idea of animals running a farm all by themselves and said that the whole thing would be over within a couple of weeks. 

They proceeded to spread vicious rumors about the farm, which they insisted on calling 'Manor Farm' instead of its new title, 'Animal Farm.' The two, for example, said that the animals were continuously fighting with each other and were also quickly dying of hunger. After some time, when it became clear that the animals were healthy and not starving, they changed their tune and started saying that there was a pervasive evil on the farm.

The two farmers gossiped that the animals were eating each other and that they were practicing torture by using red hot horseshoes. They also claimed that the male animals were sharing their females. Both of them agreed that the evil on Animal Farm was because the animals had acted against the laws of Nature. 

Although the two men did not specifically mention exactly which natural laws the animals had broken, it is easy to deduce that they were referring to the so-called laws of natural order in which man occupies the top position and all animals are subject to his rule. The animals, by taking over the farm, had overturned the status quo and upset the balance in nature. As far as the two farmers were concerned, this was an abomination and the animals deserved whatever punishment they got.

It was for this reason, more than anything else, that Pilkington and Frederick's men later decided to assist Jones and his men in an attempt to retake the farm. They failed miserably and were driven off the farm, hurt and humiliated.

Public opinion about the farm generally remained the same and every human wanted it to fail. The animals, however, gained their respect, albeit against their will, because of the efficient manner in which they managed the farm. As the text explains in chapter 6:

One symptom of this was that they had begun to call Animal Farm by its proper name and ceased to pretend that it was called the Manor Farm. They had also dropped their championship of Jones, who had given up hope of getting his farm back and gone to live in another part of the county.

Eventually, Napoleon, through a solicitor, Mr Whymper, considered entering into business dealings with the very same individuals who had been so critical at the beginning, who were more than willing to benefit.