Wow, that is scary. My husband and I both have been worried that as the economy drops, people will be looking for food in other places than grocery stores because they have no money, and we saw farms as a big target for theft. I guess we are not the only ones who think this way! 
We keep our goats and chickens both in 6 foot tall chain link pens (the style used for dog kennels) with another foot of barbed wire around the top to discourage climbing, (by the goats and by predators, but it works well on people trying to climb in too) and I've been wanting to get some good strong locks for the gates so we can lock them up when we aren't home or at night. Fortunately we have a large lot and our neighbors are not close, so it is hard to tell that we have animals or a garden. Still, it worries me! At least I know that if our animals get loose, they don't leave on their own. If the goats get out of their pens, they actually run straight for our back door and knock on it to get us to come out! And the chickens won't leave their pen at all unless I make them do so. But if someone opened the gates, and offered the animals a treat, they would follow them anywhere...