I'd like to know what some of them are please. Someone has taken to throwing food in our back yard. And call me paranoid but I'm not sure of the intent. Whether just being a pain, trying to give the dog a treat, or something more sinister. I've never seen it happen so I don't know who it is. We live in a very populated area and have an alley behind our house, which people walk down all the time. I'm going to start checking the yard in the morning before letting him roam in the yard. But please if you know the signs to poisoning I would be grateful to hear them. Thank you.