It seems that ragwort is fast becoming the subject of a nationwide
outburst of hysteria similar to that caused by salmonella in eggs (News,
). In the hope of calming it, I offer the following
Yes, ragwort is poisonous to horses, cattle and sometimes
sheep. It can cause acute liver damage in young stock, but this is rare.
It is most commonly encountered as chronic liver damage in older animals.
But ragwort is distasteful to horses and cattle, and they will eat it only
if they are half-starved on a pasture that is bare of almost anything
In the agricultural depression of the 1930s and during the
Second World War, there was far more ragwort around than there is today.
There were no selective weedkillers available, so it had to be controlled
either by hand-pulling or by allowing sheep to graze off the young plants,
which are less poisonous. There were also many more horses in the country,
working on farms or pulling delivery vans. Ragwort poisoning was a
recognised disease, but not a major problem.
Any good stockman
would not leave his animals on a bare pasture with ragwort. I find it hard
to believe that so many of today's horsemen and women leave their horses
on bare ragwort-infested pasture that 6,500 of animals succumb to ragwort
poisoning annually. I realise that some ragwort could be bought in with
hay, but ragwort is easily spotted, is normally rejected by the horse and
is in any case easily removed by the groom/ owner. It could be more of a
problem to those few horses that are fed silage.
I suggest that if
6,500 horses are dying of "ragwort-like" liver damage each year, it is
time to look for other possible toxins. Pesticides added to grain to
control weevils and mites are certainly one possibility.From:Frances Wolferstan BA,
Vet MB, MRCVS, Tamworth, Staffordshire