Text Box:   Ragwort Poisoning. Ragwort poisoning is the most common cause of liver damage in horses in the U.K. The plant Senecio jacobea is a hardy biennial. It flourishes in waste ground and roadside verges from where it invades nearby fields. Ragwort is at its most dangerous at the very beginning and at the very end of its life. An important feature of the plants' life cycle is that it is biennial. During the first year the plant produces only roots, a short stem and leaves. If the leaf is detected, it is spat out and dies, but within 2-3 days the dead leaf has lost all of its smell and bitterness and is happily eaten by the horse. As the ragwort grows, it develops a crown and a strong rosette of leaves. At this stage the plant is very noticeable and is rarely eaten by animals unless it becomes damaged by treading and dies. In year 2 the rosette bolts to flower, again, unless damaged, the large plant is rarely a hazard to stock. That is - until it starts to die off. The dead plant looses its acrid smell and bitter flavour and becomes palatable to stock - but it has retained all its toxicity! Therefore a significant risk to horses after it has died and wilted, either at the end of its second year or after moving or cutting pasture for hay. Hay from ragwort contaminated fields is thus an important cause of ragwort poisoning. The plant has a long flowering period from May to Sept during which the characteristic small yellow flowers make the plant easily detectable. However, if grass becomes sparse (e.g. following a period of hot dry weather) horses may resort to eating plants they wouldn't normally eat, including ragwort if it is present. Some horses develop a liking for the bitter taste and may choose to eat it even when there is sufficient palatable grass available to graze on Hand pulling ragwort can be a lethal activity for humans. The World Health Organisation state that there is a 74% probability of death (within 18 to 24 months) in humans presenting with ragwort induced jaundice. The problem is much worse in children. The plant can be removed from fields by the use of broadleaf herbicides or by pulling them up and burning. It will take a number of years to eliminate the plant completely. Simply mowing the fields is dangerous to horses as it contaminates the pasture with wilted plants. Symptoms of Ragwort poisoning in the horse include: - Weight loss and decreased appetite.  Depression. Neurological signs (yawning, head pressing, and ataxia). Swelling under the abdomen. Photosensitization and jaundice may be present.   Once signs have developed, especially any neurological symptoms, the prognosis is poor; however in the early stages, careful dietary control and vitamin supplementation can be helpful. Ragwort poisoning is caused by chemicals in the Ragwort plant which are toxic to the liver.  The chemicals in Ragwort do not usually cause your horse to suddenly go off colour but gradually eat away at the liver until it is too late.  The difficulty with diagnosis is that you do not see a sign of the problem until a significant proportion of this organ is already damaged. Ragwort is not only harmful to humans and horses; other farm animals such as sheep and cattle and also to wild animals such as hare and deer.   Ragwort facts: ·  Ragwort is one of the most frequent causes of plant poisoning of livestock in Britain. ·  Equines and bovines are more susceptible to ragwort poisoning than other livestock. ·  Young animals are more at risk than mature animals. ·  Ragwort is also harmful to humans. It can enter the bloodstream through the skin: protective clothing MUST be worn when handling the plant. ·  Overgrazed land provides ideal conditions for ragwort growth and spread. Due to the lack of grass cover, the plants are more likely to be eaten. ·  Each plant can produce up to 150,000 seeds with a 70% germination rate. ·  Ragwort seeds can be dormant in the soil for up to 20 years. ·  Fragments of root left behind in the soil when the plant is removed can re-grow. ·  Ragwort poisoning can occur at any time of year, so remain vigilant year-round. ·  Ragwort acts as a cumulative poison, eventually destroying the liver. A small intake of ragwort over a long period can be just as damaging as a larger intake on a single occasion. ·  Little can be done for an animal once the clinical symptoms appear.