Cause.—The cause of this disordered state of the digestive system in cattle is usually obscure, but has in some cases been traced to a partial closure of the opening into the second stomach or to a distention of the esophagus. It has been found to occur when there was cancerous disease of the fourth stomach, and experimentally it has been shown that a suspension of digestion or great derangement of this stomach produces considerable nervous disorder of the rumen and sometimes vomiting or attempts to vomit.
Treatment.—Easily digested feed and plenty of water should be given. Fear and excitement, chasing, or hurrying animals after they have eaten heartily are liable to bring on this result. In order to overcome irritation which may produce vomiting the following draft should be given: Hydrate of chloral, half an ounce; water, 1 pint. The dose must be repeated when the condition of the animal seems to require it. As a rule, treatment is not successful.
DEPRAVED APPETITE (PICA).
Cattle suffering from this disease have a capricious and variable appetite as regards their ordinary feed but evince a strong desire to lick and eat substances for which healthy cattle show no inclination. Alkaline and saline-tasting substances are especially attractive to cattle having a depraved appetite and they frequently lick lime, earth, coal, gravel, and even the dung of other cattle. Cows in calf and young cattle are especially liable to develop these symptoms. Animals affected in this way lose condition, their coat is staring, gait slow, and small vesicles containing yellow liquid form under the tongue; the milk given by such cows is thin and watery. Such animals become restless and uneasy, as is indicated by frequent bellowing. The disease may last for months, the animal ultimately dying emaciated and exhausted. Depraved appetite frequently precedes the condition in which the bones of cattle become brittle and fracture easily, which is known as osteomalacia.
Cause.—From the fact that this disease is largely one of regions, it is generally believed that some condition of the soil and water and of the local vegetation is responsible for it. It is more prevalent some years than others, and is most common in old countries, where the soil is more or less depleted. Cattle pastured on low, swampy land become predisposed to it. It occasionally happens, however, that one individual in a herd suffers though all are fed alike; in such cases the disease must arise from the affected animal's imperfect assimilation of the nutritive elements of the feed which is supplied to it.
Treatment.—The aim in such cases must be to improve the process of digestion and to supply the animal with a sufficiency of sound and wholesome feed. The following should be given to the cow three times a day, a heaping tablespoonful constituting a dose: Carbonate of iron, 4 ounces; finely ground bone or "bone flour," 1 pound; powdered gentian, 4 ounces; common salt, 8 ounces; powdered fenugreek, 4 ounces; mix. In addition to this, 3 tablespoonfuls of powdered charcoal may be mixed with the feed three times a day, and a piece of rock salt should be placed where the animal can lick it at will. German veterinarians have had brilliant results from the treatment of this disease with subcutaneous injections of apomorphin in doses of 1½ to 5 grains for three or four days.
HAIR CONCRETIONS.
Hair concretions, or hair balls, result from the habit which some cattle have of licking themselves or other animals. As a result the hairs which are swallowed are carried around by the contractions of the stomach and gradually assume the form of a small pellet or ball. This increases in size as fresh quantities of hair are introduced into the stomach and adhere to the surface of the ball. These balls are found most frequently in the reticulum or second stomach ([Pl. II], B), though sometimes in the rumen. In calves hair balls are generally found in the fourth stomach. There are no certain symptoms by which we can determine the presence of hair balls in the stomach, and therefore no treatment can be recommended for such cases. In making post-mortem examinations of cattle we have sometimes found the walls of the reticulum transfixed with nails or pieces of wire, and yet the animal had not shown any symptoms of indigestion, but had died from maladies not involving the second stomach.
INDIGESTION (DYSPEPSIA, OR GASTROINTESTINAL CATARRH).
Tympanites, already described, is a form of indigestion in which the chief symptom and most threatening condition is the collection of gas in the paunch. This symptom does not always accompany indigestion, so it is well here to consider other forms under a separate head. If indigestion is long continued, the irritant abnormal products developed cause catarrh of the stomach and intestines—gastrointestinal catarrh. On the other hand, however, irritant substances ingested may cause gastrointestinal catarrh, which, in turn, will cause indigestion; hence, it results that these several conditions are usually found existing together.