Had to put down a heifer this afternoon. Above symptoms obvious but no St john's Wort preesent on our property in Australia. Muscles/nervous system seemed to also be effected as they were constricted, particularly around the face/neck and gut. Skin peeling off in large chunks around necck adn all skin around nose face was peeling off. Quite strange adn I haven't got a clue what it was, have never seen this before. Any thoughts out there?