Huge Error Re: Sheep

Between Dale and his father's rambling about the huge number of sheep on the manor's grounds, we are told that the sheep operation ended when all the sheep had to be killed because of foot and mouth disease.

There has not been any foot and mouth disease in the United States since 1929. That is the same year actor Christopher Plummer, portraying Dale's father, was born, and he would hardly be playing someone old enough to have remembered an outbreak that year (from the cradle?), let alone involved in killing sheep. If his son is about the same age as the actor portraying Dale, he was born in 1973 and would know nothing first-hand of any such disease in his homeland, much less on his farm. It is a key to the relationship between the two that the father ridicules the son over not being able to kill animals, even with the bolt "gun" that replaced the hammers, which is certainly what the father was describing during Cooper's visit. This also indicates that the FMD incident occurred in the son's lifetime.

http://www.aphis.usda.gov/lpa/pubs/fsheet_faq_notice/fs_ahfmd.html
(for the doubters among you)