This lumbricoid is the principal round-worm found in dogs; it resembles the common earth-worm, and varies in length from two to six inches. It is of a pale pink color, perfectly round in shape, and tapers towards each extremity.

Round-worms inhabit the small intestines, often migrating into the stomach, from which they are expelled by vomiting; but more often they seek the large intestine and pass out with the discharges. In rare instances they have been known to wander into the gall bladder and biliary ducts, giving rise to abscess of the liver; even the pancreatic duct has not escaped invasion.

That certain special conditions are required for the formation of roundworms is evident from the fact that they are more common in puppies and young dogs. As regards the nature of the conditions, little or nothing is known; mucus in abundance is supposed to be the repository of the ova or eggs from which they are propagated. The female roundworm is marvelously productive. Eschright estimated in the body of the female lumbricoid found in the intestines of man, the number of eggs to be sixty-four millions. These are discharged with the feces and retain their vitality for many months. It is conjectured that ova are introduced into the intestinal canal through the medium of the drinking water and food.

Symptoms

Symptoms denoting the existence of these or other worms within the Intestinal canal are in some instances obscure, in others prominent. At times but little derangement is noted; again profound disturbance results.

The morbid effects of worms in dogs cannot be exaggerated; that they may give rise to convulsions, chorea, paralysis, and other affections of the nervous system is very generally conceded.

The more common symptoms denoting worms are great abdominal distension or bloating, vastly disproportionate to the amount of food taken, indigestion, colic pains, diarrhoea, vomiting, emaciation, voracious appetite, nose hot and dry, cough, offensive odor to the breath, disturbed, dreamy sleep, and a rough, dry, harsh coat.

Frequently puppies and more rarely old dogs partially lose the power of their hind legs, and rapidly recover as soon as a discharge of worms occurs. Paralysis induced by this cause is functional and rarely if ever complete.

Treatment

For the expulsion of the round-worm numberless drugs have been advised. It must be remembered that natures and conditions vary; remedies which in some cases are effectual in others are Inactive; for this reason, when there is presumptive evidence of the existence of worms, absolute dependence should not be placed upon any one agent, but others should be given alter a proper interval has been allowed.

Treatment for round-worms should always be premised by fasting and a purgative. Food should be denied puppies for twelve hours at least, and old dogs twenty-four hours. Castor oil is the better purgative to administer, and should be given six or-eight hours before the worm medicine is employed.

Among the more reliable agents destructive of round-worms, santonine in two grain doses, is one of the most active; it is insoluble or nearly so, and passes into the small intestines and acts on them as a poison. It will be easily taken in pill form mixed with lard, and can be given two or three times a day; after the second or third day a generous dose of castor oil should be administered and the santonine discontinued.