Island Life Magazine Ltd August/September 2012 | Page 109

EQUESTRIAN
Certain worms can live as parasites in

HOW DO I KNOW IF MY HORSE HAS

your horse’s faeces on a regular basis and

the intestines of horses and ponies and

WORMS?

administering 'wormers' only when needed.

large numbers can cause many problems

Recent research has shown that within a herd

The aim with worm control is establishing a

including colic, weight loss, diarrhoea, poor

80% of the worms will live in only 20% of the

balance between worm burden and horses

performance and in extreme cases even

horse population. In other words, most of the

health.

death. Therefore controlling the level of worm

horses will be free of worms while only 1 or

infection is very important to maintaining a

2 of that herd will bear a heavy burden. The

decreasing the number of worms that live in

healthy horse. However it is not as simple

simplest way to know if your horse has worms

your field and therefore decreasing chances

as you might think! Strangely a low level

is to use a faecal worm egg count. This gives

of infestation. You can take measures such

of infection with worms may sometimes

a direct measurement of the level of infection

as regularly poo picking fields and getting

be beneficial – moderate infection with

that your horse has. There is, however, one

horses to co-graze with either sheep or

cyathostome worms seems to be protective

type of worm that is not possible to detect

cattle, they will eat horse worms and destroy

against equine grass sickness. Similar

on the droppings which is the tapeworm.

them through their normal digestion process

surprising results have also been found

The only way to establish whether there is a

without having an ill effect.

in human medicine where it has been

tapeworm infestation is through a blood test.

There are also simple and practical ways of

discovered that people with hookworm

SPECIAL PRECAUTIONS

infections are less likely to get asthma

• Tapeworm infestation tends to be higher

and people with low levels of whipworm

amongst horses between the ages of 6

infection show an improvement in signs of

months to 2 years. These animals should be

inflammatory bowel disease!

monitored closely for infection.
• Horses of unknown background could
potentially carry a heavy worm burden.
Prevent these horses sharing grazing with
other horses until they have been tested for

Gut i mpa cte d wit h a
s
he av y inf ect ion of wo rm

worms because they could be shedding high
levels of worm eggs into the field. Also care
should be taken when de-worming these
horses if they have a high level of infection.

WHEN SHOULD I USE “WORMERS”?

A very effective wormer may destroy all the

Traditionally most horse owners have given

worms living in the horses gut at a single time

“wormers” to their horses on a regular

and lead to a blockage of the gut by a mass

basis using different drugs depending on

of dead worms.

SO WHAT IS RIGHT?

the time of the year. However, if we are

• When treating very underweight horses or

What we can conclude is that intestinal

routinely de-worming all horses, apart from

foals with a high worm burden care should

parasites are associated with colic and

wasting drugs (as explained above as 80%

be taken with the choice of “wormer”. In

those horses with high infection intensity

probably won’t have worms!) we are also

these animals “equest” can be strongly

are at highest risk. The risk of colic can

contaminating the ground with chemicals that

contraindicated as this drug accumulates in

be minimised by preventing high levels of

in time, due to prolonged exposure worms will

horse’s fat. In underweight horses and foals

infection but low levels of parasitism should

gain resistance to.

there is less fat and so a higher level of drug

Strong yle eggs seen u nder the microscope
in a fa ecal worm egg cou nt

be tolerated and may bring health benefits.

Worm resistance to these chemicals is
already a reality and is becoming such a

How does my horse get worms?

problem that in the pro f