These cats get routine vet checks every month. Every month! They are selectively bred, cats not considered to be prime candidates for mating will be altered. The cats are cared for better than most cats are. the kittens and the mom cat are isolated for three months after birth to protect them until they can be vaccinated. The government is campaigning to put them in cages, stipulating that the cat proof fence that runs around the grounds isn't good enough. Do some cats slip through from time-to time? Yes, but they are quickly recovered.
it is interesting to note that in the area where these cats are housed, you can walk down the street and see feral chickens everywhere. They peck at your feet, leave droppings everywhere and are a true health issue, these Hemingway cats are not a health issue. Surely, the government has bigger fish to fry elsewhere?