52 
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‘The worms which invade the horse most commonly, are the ascaris 
megalocephala, or the large-headed lumbricoid worm, and the little oxyuris 
“curvula or maw worm. The male of the lumbricoid worm is rarely over 
seven inches, but the female may attain a length of sixteen to eighteen 
inches. This worm has a smooth body with transverse rings, and it may 
‘occur in any part of the intestinal canal, although it is especially found in the 
small intestines. The horse is known to be invaded by these parasites by 
their occasional passage out of the body with the excrement. 
It is noteworthy that the eggs of the lumbricoids effectually resist dryness, 
and it is possible that horses become infected with this parasite, by drinking 
out of ponds containing sewage matter. In cases of invasion by this parasite, 
the horse should havea full and nutritious diet. In the first instance, it is well 
to give a ball containing six drachms of aloes and one drachm of tartar 
emetic. Two or three days afterwards, a ball consisting of santonine thirty 
grains, of sulphate of iron one drachm, of carbolic acid fifteen drops, of aloes 
one drachm, made up with ginger and gentian and treacle to one_ounce, may 
be given twice daily for three or four days. 
The oxyuris curvula, or maw worm, is partly transparent, and is 
marked with transverse stripes. In length, the males are one and three 
quarters of an inch, and the females from three to four inches or more. This 
worm has a long tail. Its usual habitat is in the large sacculated bowel, 
where it may set up much local irritation. 
The horse rarely requires treatment for the expulsion of this worm. A 
full dose of aloes may be administered, and clysters given once daily for a 
few days will prove beneficial. Each clyster may be made of two ounces of 
the oil of turpentine, with mucilage of starch one pint. 
We will now turn our attention to two other kinds of worms which 
not infrequently infest the horse. One is called the four-spined strongyle 
(Strongylus Tetracanthus), the other the armed strongyle (Strongylus 
Armatus ). 
The four-spined strongyle is sometimes found in large numbers in the 
horse, ass, and mule, and, though not uncommon in this country, is not so 
frequently met with on the continent. The males and females are of about 
equal size, and occupy the walls of the large intestines of their hosts. They 
set up by their presence localised congestion and inflammation, and the 
formation of matter in the wall of the gut. The species is recognised by its 
bright red colour, by the four conical spines surrounding the mouth, by two 
neck bristles, and by the three-lobed long head of the male. The head, 
when viewed in profile, is truncated, and seen from above it appears round. 
The body is smooth, and presents indistinct rings. The eggs of the worm 
probably gain access to the intestines of small insects, and the immature 
form is swallowed by the horse in the water or in the food. The worms then 
become encapsuled in the lining membrane of the large gut. They are then 
about 3°6 millimetres long when uncoiled. 
In this condition the worms cast their skins. They enter the cavity’ 
of the gut, and undergo another change of skin prior to acquiring the 
