Aneurisms impede the circulation of the blood
Aneurisms impede the circulation of the blood, and may give rise to
intermittent lameness. The aneurism may rupture, since it constitutes a
weak place in the wall of the blood vessel, and the horse die of the
resulting hemorrhage. Particles of blood clots in the aneurisms may
break off and plug a blood vessel at the point where they lodge, thereby
causing the death of the part from which the blood is shut off and
occasioning a type of colic which often terminates fatally. The larvae of
Cylicostomum form cysts in the walls of the large intestine, and when
these open they give rise to small sores; when they are numerous they
cause a thickening and hardening which impair the proper functioning of
the intestine. Abscesses sometimes perforate, causing death. The adult
worm attacks the intestinal wall, causing bleeding which results in
anemia. The numerous small sores thus caused allow bacteria to get into
the circulation, sometimes resulting in localized abscesses or in septic
arthritis or joint disease.
PLATE V.
INTESTINAL WORMS.
PLATE VI.
BOTS
1. Bots in the stomach.
2. Bots in the duodenum.
The disease due to these worms is quite common. The worms enter the body
as immature forms in the spring, when the animal is turned out on
pasture. The first symptoms show in November or December, the disease
being in a latent stage during the development of the worms. The first
symptoms are diarrhea, loss of appetite, and emaciation. The animal
becomes anemic. Secondary symptoms are edema and such complications as
joint infection, colic due to embolism, and accidents from falls,
hemorrhage from ruptured aneurisms, or perforation at the site of
abscess. The animal may die, recover, or become a chronic sufferer, the
internal injuries failing to make a satisfactory recovery even with the
removal of the worms in chronic cases.
Treatment calls for the expulsion of the adult worms from the
intestine, the development of the body resistance to repair the damage
wrought by the developing worms, and the combating of complications. For
the expulsion of the worms the use of carbon bisulphid in gelatin
capsules, 2 to 5 grams, according to the size of the patient, for five
days, followed by magnesium sulphate the sixth day, has been
recommended. Owing to the difficulty and danger in the administration of
carbon bisulphid in capsule, it is advisable to call in a veterinarian.
Tonic treatment consists in the subcutaneous administration of
artificial serum and caffein. The various complications of bacterial
infection, colic, heart depression, etc., call for the attention of a
veterinarian. Preventive measures consist in avoiding reinfection with
worms so far as possible by using dry upland pasture in preference to
low, wet land, and by rotating pastures or rotation of the stock on a
given pasture. Horses may be alternated with cattle, sheep, or hogs to
advantage, so far as parasites are concerned. Another feature, always of
importance, is the provision of a pure, potable drinking water.
Bots (Gastrophilus spp.). Bots (Pl. VI) are quite common in the
stomach and upper part of the small intestine of the horse anywhere in
the United States, one kind being occasionally found in the rectum. They
attach to that portion of the mucous lining of the stomach nearest the
esophagus or sometimes around the pyloric opening to the intestine or
even in the upper intestine, and undoubtedly interfere with the proper
functioning of the stomach and the health of the animal to a certain
extent. The symptoms are rather vague as a rule, but the general result
is a condition of unthriftiness.
A treatment which has been found effective consists in feeding lightly
on the day preceding treatment, withholding food in the evening and
giving an ounce of Barbados aloes or a pint of linseed oil. The next
day give 3 drams of carbon bisulphid in a gelatin capsule at 6 o'clock,
repeat the dose at 7 o'clock, and again at 8 o'clock, making a total of
9 drams altogether for an adult horse; half that amount will be
sufficient for a yearling colt. As previously noted, there is some
little difficulty and danger of accident in the administration of
treatments of this character and it is advisable to call in a
veterinarian.
Unless destroyed by treatment, the bots in the stomach of the horse pass
out in the manure in the spring and burrow down into the soil an inch or
two. Here they undergo a certain amount of development and finally
emerge as adult flies. These bot flies mate and during the summer the
eggs are deposited by the female on the forelegs and shoulders or around
the chin, mouth and nostrils of the horse, the location and appearance
of the eggs varying somewhat with different species of bot flies. These
eggs or the young maggots escaping from them are ingested by the horse
in licking the portions irritated by the movement of the escaping
maggots, and when swallowed develop to form bots in the stomach. Careful
currying, especially around the forequarters, is an aid in keeping down
bot infestation, but this is not commonly feasible with horses on
pasture, the ones most liable to become infested.
Fonte: Diseases of the Horse