Springtime.
A collective sigh of relief goes up around the country as horses can spend more time turned out.
But beware.
With the surge of grass growth comes an increased risk of laminitis.
Acute laminitis should be treated as an emergency.
Within only a few hours the disease can cause permanent damage to the feet.
So, if you think your pony has laminitis, ring the vet straight away.
The sooner treatment can be started, the better the chance of limiting the damage.
What are the signs of acute laminitis? Often the first indication is that the pony spends more time standing still in the field.
He is reluctant to move, often leaning backwards to take his weight of his front feet.
Obviously it is much better to prevent your pony getting laminitis in the first place.
Recently the mechanisms behind pasture -associated laminitis have become a little clearer.
But the full story is still not completely understood.
The main culprits appear to be fructans, large carbohydrate molecules used by the grass for storing energy.
Horses can not digest fructans.
So they pass into the hindgut unchanged, where they are rapidly fermented by bacteria.
The gut contents become more acidic, disturbing the balance of bacteria and micro-organisms.
Bacteria that can survive under the acidic conditions increase dramatically in number; those that cannot, die.
Potent chemicals are released, which may trigger the laminitis.
So, to reduce the risk of laminitis it is important to limit the intake of fructans.
The fructan content of the pasture is influenced by factors such as the amount of sunlight, temperature and stage of growth.
Fructans are found in significantly greater amounts in the stem than in the leaves.
The amount of fructans present in the grass also varies during the day.
Generally there is less at night and early in the morning.
Certain grasses, such as timothy, tend to have larger fructan molecules.
These may be fermented more slowly in the hindgut and so may be safer than other grasses.
Some horses and ponies are more susceptible than others to the condition.
One pony may be able to gorge himself without developing lamintis; another may go down with the disease at the first taste of grass.
Recent research has found a way of identifying those ponies that are likely to develop laminitis.
All that is needed is the pony's condition score, and a simple blood sample.
Ask your vet for details (or see http://www.
equinescienceupdate.
co.
uk/plms.
htm).
There is also some convincing evidence that ponies with laminitis are more likely to come from mares that have themselves had laminitis.
Identifying susceptible ponies allows them to be managed with special care.
This may reduce the risk of them developing laminitis.
So what can you do to reduce the risk of laminitis?

• Restrict grazing in spring and autumn when the fructan and water soluble carbohydrate levels are high.
  
• Turn horses onto pasture late at night and bring them in before mid-morning, so they are grazing when the fructan content is likely to be lowest.
  
• If you can, choose pasture that is regularly grazed or cut (the grass stems tend to have high fructan content) and contains species such as timothy that produce lower levels of fructans.
  
• Don't use stubble grazing (i.
  e.
  after it has been cut for hay) - because the stems are likely to have a high fructan content.
  
• Don't turn horses onto pasture that has been exposed to frost and bright sunlight.
  (The sunlight produces energy, which the grass cannot use for growth because of the cold, and so it is stored as fructan).
  
• Consider using a muzzle to prevent the pony eating too much.
  Or, if you really cannot control the grass intake any other way, keep the pony in the stable and feed hay with a vitamin/mineral supplement.
  

Remember that it is so much better to take steps now to prevent laminitis occurring, than to have to treat your horse or pony for this painful disease.