Cause
The cause remains unknown, however present research suggests that toxin production from the bacterium Clostridium botulinum type C is involved.
Clostridium botulinum is a soil-borne bacterium, which may be better known for producing clinical signs of botulism. Research has suggested that Clostridium botulinum may cause grass sickness when the spores of C. botulinum type C are ingested and produce their toxin locally within the intestine.
Read more about this topic: Grass Sickness