| Calves | 3½ to 4 | fluid ounces. |
| Yearlings | 6 | fluid ounces. |
| Two-year-olds and over | 12 to 16 | fluid ounces. |
ROUNDWORMS.
A large roundworm (Ascaris vitulorum) measuring 6 to 12 inches in length, sometimes found in the intestines of cattle, especially calves, may cause inflammation and occasionally rupture of the intestine. Infection occurs through the swallowing of the eggs of the parasite in feed or water which has been contaminated with the feces of infested cattle.
A number of species of small roundworms, varying in size from an eighth of an inch to an inch or more in length, occur in the intestines. Of these may be mentioned the hookworm (Bunostomum phlebotomum) and the nodular worm (Œsophagostomum radiatum). The former is about an inch long and is found in the small intestine. The latter is somewhat smaller and is found in the cecum and large intestine. Hookworms, when numerous, may cause anemia and other symptoms similar to those caused by stomach worms (see [p. 519]). The injury to the mucous lining of the intestine from the bites of hookworms may cause severe inflammation, and affords an avenue of infection with the germs of various diseases. The adult nodular worms apparently do not attack the wall of the intestine, but derive their nourishment from the intestinal contents. Several species of small, very slender roundworms (Trichostrongylus), less than a quarter of an inch in length, sometimes occur in the small intestine and fourth stomach, and a severe gastroenteritis, or inflammation of the stomach and intestines, has been attributed to them. One species of small roundworm (Cooperia punctata) burrows in the wall of the small intestine and causes caseous nodules in the mucous lining. This parasite sometimes occurs in very large numbers in the intestines of cattle in certain sections of the country, and apparently does considerable damage.
Nodular disease of the intestine, due to young nodular worms which burrow in the intestinal wall during a certain stage in their life history, sometimes apparently produces serious effects, particularly in young cattle, but commonly has little or no perceptible influence on the general health. It, however, often renders the intestine unfit for use as sausage casings, and as it is widely prevalent among cattle the loss from this source is considerable. The greenish or yellowish nodules with cheesy contents are frequently mistaken by the inexperienced for lesions of tuberculosis.
The life histories of the various small roundworms occurring in the intestines of cattle, so far as they have been worked out, are very similar to that of the twisted stomach worm as described on [page 519].
Treatment for intestinal roundworms.—The preventive measures are similar to those recommended in the case of the twisted stomach worm ([p. 521]). Medical treatment is generally not very satisfactory. According to the Oklahoma Experiment Station, the addition of 1 per cent of tobacco to the bluestone solution used in the treatment of stomach worms in sheep is effective in the removal of hookworms. The bluestone and tobacco mixture described on [page 524] may be of value in the treatment of hookworms in cattle. It is asserted by one author that 2 or 3 drams of rectified empyreumatic oil in a mucilaginous emulsion, followed the next morning with a purgative of 1 to 1½ pounds of sulphate of soda, will expel the large roundworms (Ascaris vitulorum).
PROTOZOA.
A number of species of protozoa have been reported as parasites of the intestines of cattle. To one species has been attributed a serious disease of cattle in Switzerland known as red dysentery, but so far comparatively few cases of this disease have been recorded in America. It is probably more common than is generally supposed. Calves particularly seem most likely to be affected.