I looked after a horse on livery who suffered from Rag poisioning, the yard we were at (he had been there about 5 years and owner had him since he was 4) had no Rag anywhere.
He started to just be a little off color, not overly keen to work (he was a 17 yo ex-racer tb and normally very keen) he was still eating and peeing etc normaly. To start with we (we being livery staff and horses owner) just thought he had a low grade virus or something so gave him a few days off and kept him well wrapped up. When it didn't get any better after a couple of days the vet was called, there were discussions of azotoria as he was getting stiff and not happy to move. After bloods had been run it was found that he was heading for liver faliure.
The vet still had a small hope to pull him through, he was put onto drips and all sorts to try to flush his system etc. I stayed up for 3 days and nights to keep his drip going etc, on the third day it got very worrying, he started to stagger about and didn't really seem to be aware of what was around him anymore. That night he was PTS as the toxins in his body had reached critical lavels in his brain and he was totally unaware of his surroundings and had started walking straight into the walls and things causing himself real damage and he didn't even know it
They did further checks on him, the decided it was likely that this horse had been poisioned as a baby, probably when he was turned out after weaning before his race training. The concluded that the poisioning had been bad at that stage, but not bad enough to finnish him, the damage is never repaired and as he got older and needed treatments (drugs/wormers etc) his system had finally been overloaded, so even though his owner had always been super careful, just that short period when someone was not was then end of a really lovely chap.
Ragwort is definatly a killer, don't underestimate it, don't even risk it if you are not sure. Watching this poor horse die within 2 weeks of symptoms showing was terrible.
J x