Poisonous plants didn't seem to be an issue for the cattle and hogs around where I grew up. They seem to know when something's not to be eaten...with certain exceptions of course.
We kids had a lot of fun playing with the magnet boluses that dad kept on the shelf of his veterinary office. Those magnets were shot down the throats of cows who had ingested things like bits of barbed wire and other metal bits to pull them all together and keep them from passing through the whole digestive tract. The fact that the magnets were administered with a balling gun prompted a bit of Beavis and Butthead level chuckling.
We kids had a lot of fun playing with the magnet boluses that dad kept on the shelf of his veterinary office. Those magnets were shot down the throats of cows who had ingested things like bits of barbed wire and other metal bits to pull them all together and keep them from passing through the whole digestive tract. The fact that the magnets were administered with a balling gun prompted a bit of Beavis and Butthead level chuckling.