As ever on these disgusting farms, we smelt the bears before we saw them. The door creaked open and 10 pairs of eyes blinked at us out of their cages in the gloomy half light. It was only about 9 o'clock in the morning, but a grey smog hung in the air and the farm seemed all the more depressing for it. Rainbow told us that the red and gold sign above the door proudly announced "peace in four seasons" – which is ironic given that it has been anything but peaceful for the victims inside.