Page 839 - The Veterinary Care of the Horse

vaccine against ringworm.

VetBooks.ir Prognosis

If the condition is recognized early and the owner has the time and facilities to manage it
well, many horses with a susceptibility to sweet itch develop only mild signs with occasional

rubbing. However, in other cases the prognosis is guarded. The disease can be both
debilitating and disfiguring. It prevents the animal being used for showing and the sores may

limit riding in the summer.
Sweet itch is costly in time, effort and money. Not surprisingly, affected animals may

become bad-tempered and unreliable. The condition tends to get worse each year. Moving
the horse or pony to another environment may help. However, there are some ponies who

reach a state where no treatment is effective and every summer is a time of torment and
misery. In these cases, euthanasia may have to be considered.

Warning

Many of these animals are sold during the winter months and the problem is
passed on to another unsuspecting owner. Potential purchasers should always be

warned about the condition as these horses and ponies require special attention and
should go to experienced homes with suitable facilities.

The National Sweet Itch Centre (www.itchyhorse.co.uk) has a helpline and web site

providing advice on how to cope with this problem and additional information on the Boett ®
blanket.

LICE INFESTATION

There are two types of lice that live on horses. Haematopinus asini, the sucking louse, feeds
on blood and tissue fluids. Damalinia equi, the biting louse, feeds on scurf and other debris

on the skin surface. Infestations usually occur in the winter months and early spring when the
coat is long. They do not breed when the temperature is above 38 °C (100 °F) and they die if

exposed to temperatures of above 50 °C (120 °F). Most lice do not survive the summer
months as these temperatures may be reached within the hair coat.

Lice are visible to the naked eye. They are 1.5–3 mm (up to in) long and light brown to