An interesting survey from Freedom Food has shown how little the public knows about farm animals:

75% of people didn't know that a sheep can recognise 50 members of its flock
74% didn't know that farmed male turkeys cannot mate
73% didn't know that chickens communicate using 20 different types of call, including one for each type of predator.
70% didn't know that chickens usually live for 5 weeks prior to slaughter
66% didn’t know a dairy cow produces on average 11993 pints of milk each year
60% didn't know that 63% of chickens are kept in battery cages

Mind you, some pretty obscure facts here. I wonder how many vets would have known all the answers.