INTESTINAL WORMS OF SHEEP.—The most widely distributed and seemingly most injurious intestinal worm of sheep is the OEsopliagostomum columbianum. It is a small worm from 0.5 to 0.75 inch (12 to 18 mm.) long. It penetrates the lining membrane of the intestines and encysts in the intestinal wall. A tumor, varying in size from that of a millet seed to a hazelnut, then forms in the wall of the intestine. These tumors undergo a cheesy degeneration, and when mature, may appear as greenish, cheesy-like masses, covering a large portion of the lining membrane of the intestine. Diarrhoea and emaciation may result. These symptoms are most evident during the winter months.
The treatment recommended for ridding sheep of this intestinal worm is largely preventive. Very little can be done with the medicinal treatment of a sheep whose intestinal tract is badly infested with this parasite. Good care and the feeding of a proper ration are the only curative measures that are effective in such cases. The occasional administration of a vermifuge for the purpose of ridding the digestive tract of worms, together with the frequent changing of pastures during the spring and summer, are the most effective preventive lines of treatment. The same treatment recommended for stomach worms may be used for this disease.
INTESTINAL PARASITES OF HOGS.—The Ascaris suis or common round worm is very commonly found in the small intestine. It is quite frequently found in large numbers, almost filling the lumen of the intestine of an unthrifty pig (Fig. 75). It may also work its way into the bile duct. Sometimes, after a hog has died, this parasite migrates forward into the stomach and gullet. The A. suis is from 4 to 10 inches (10 to 26 cm.) long.
The Echinorhynchus gigas or thorn-headed worm is the most dangerous of all intestinal worms (Fig. 74). It is usually found with its proboscis or thorn imbedded in the wall of the small intestine. The Echinorhynchus is not as common a parasite as the Ascaride, and it is not usually present in large numbers. Usually, not more than a half-dozen of these worms are found in the intestine of a hog, but in some localities and in hogs that are allowed to root around manure piles and in clover pastures the herd may become badly infected with them and serious losses occur. The average length of the male is about 3 inches (8 cm.) and the female 10 inches (26 cm.).
[Illustration: FIG. 77.—Whip-worms attached to wall of intestine.]
[Illustration: FIG. 78.—Pin-worms in intestine.]
The Trichocephalus crenatus or whip worm (Fig. 77) is slender or hair-like in its anterior two-thirds and thick posteriorly. It is from 1.5 to 2 inches (40 to 45 mm.) long. It is found in the caecum attached to the wall by the hair-like portion.
The OEsophagostomum dentatum or pin worm is from 0.3 to 0.6 inch (8 to 15 mm.) long. It is found in the large intestine (Fig. 78).
The symptoms of intestinal worms are not very evident in the average drove of hogs. None of the other farm animals are such common hosts for intestinal worms as hogs. But it is only in extreme cases of infection by intestinal worms, and in stunted and poorly-cared-for hogs, that very noticeable symptoms of disease are manifested. We must not take from the above statement that it is unnecessary to resort to treatment unless in exceptional cases. Intestinal worms interfere with the growth of young hogs, and may irritate and inflame the intestine, causing chronic indigestion, nervous symptoms, and in some cases death. This irritated and inflamed condition of the intestine is best noted in the abattoir by the ease with which the wall of the intestine that contains large numbers of worms tears when handling it.
The treatment of intestinal worms in hogs is both preventive and medicinal. If the conditions in the pens and houses are such as to enable the eggs and embryos to live for a long time, or the surroundings are favorable for infection of the animals through their feed and water supply, the herd may become badly infested with intestinal parasites. The preventive treatment consists in keeping hogs in clean, well-drained yards or pastures, and feeding them from clean troughs and concrete feeding floors that can be washed, when necessary, in order to keep them clean. Turpentine, given in a milk emulsion, is a common remedy for intestinal worms in hogs. The dose is one teaspoonful for every eighty pounds weight. This dose should be repeated daily for three days. The following vermifuge can be recommended: Santonin three to five grains, calomel five to eight grains. This is sufficient for one hundred pounds weight. If the pigs are small and it requires two or three to weigh one hundred pounds, the large dose should be given. If the hogs weigh one hundred pounds or more, they should receive the small dose. The drove should be divided into lots of ten or fifteen hogs each. The drugs should be mixed and divided into the same number of powders as there are lots of hogs. Ground feed is placed in the trough, dampened with milk, or water and the powder sprinkled evenly over it. The hogs are then allowed to eat the feed. It is best to dose them in the morning after they have been off feed for ten or twelve hours.