OVERLOADED (IMPACTED) RUMEN.
Definition. Causes, excess of rich unwonted food, gastric torpor, paresis, starvation, debility, partially ripened, poisonous seeds, paralyzing fungi or bacteria, lead, cyanides, congestion of rumen, chlorophyll, acrids, dry, fibrous innutritious food, lack of water, enforced rest on dry food, over-exertion, salivary fistula or calculus, diseased teeth or jaws, senility. Symptoms, suspended rumination, inappetence, anxious expression, arched back, bulging pendent left flank, impressible, no friction sounds, excessive crepitation, hurried breathing, colics, grunting when moved, diarrhœa, stupor, cyanosis. Signs of improvement. Phrenic rupture. Diagnosis from tympany, pneumonia, or gastro-intestinal catarrh. Treatment, hygienic, antiseptic, stimulants, puncturing, purgation, rumenotomy.
Definition. The overdistension of the rumen with solid food is characterized by two things, the excess of ingesta which produces the torpor or paresis which is common to all over-filled hollow viscera, and the comparative absence of fermentation and evolution of gas. If the ingesta is of a more fermentescible nature the rapid evolution of gas occurs before this degree of repletion with solid matters can be reached, and the case becomes one of tympany, but if the contents are comparatively lacking in fermentability they may be devoured in such quantity as to cause solid impaction.
Causes. Overloading of the rumen is especially common as the result of a sudden access to rich or tempting food to which the animal has been unaccustomed. Accidental admittance to the cornbin, breaking into a field of rich grass, clover, alfalfa, corn, sorghum, vetches, tares, beans, peas, or grain, or into a barrel of potatoes or apples will illustrate the common run of causes. A pre-existing or accompanying torpor or paresis of the stomach is a most efficient concurrent cause, hence the affection is especially common in animals debilitated by disease or starvation, but which have become convalescent or have been suddenly exposed to the temptation of rich food. For the same reason it is most likely to occur with food which contains a paralyzing element, as in the case of the following when they have gone to seed but are not yet fully ripened: Rye grass, intoxicating rye grass, millet, Hungarian grass, vetches, tares and other leguminosæ, and to a less extent, wheat, barley, oats and Indian corn. The same may come from the paralyzing products of fungi or bacteria in musty fodder or of such chemical poisons as lead, and the cyanides.
A catarrhal affection of the rumen, and the congestion produced by irritant plants, green food with an excess of chlorophyll, and the whole list of irritants and narcotico-acrids, will weaken the first stomach and predispose to overdistension.
Anything which lessens the normal vermicular movements of the rumen and hinders regurgitation and rumination tends to impaction, and hence an aliment which is to a large extent fibrous, innutritious, and unfermentable, such as hay from grass that has run to seed and been threshed, the stems of grasses that have matured and withered in the pastures, fodder that has been thoroughly washed out by heavy rains, sedges, reedgrass, rushes, chaff, finely cut straw, and in the case of European sheep, the fibrous tops of heather contribute to this affection. Lack of water is one of the most potent factors, as an abundance of water to float the ingesta is an essential condition of rumination. Hence pasturage on dry hillsides, prairies or plains, apart from streams, wells or ponds is especially dangerous unless water is supplied artificially, and the winter season in our Northern states, when the sources of drinking water are frozen over, and when the chill of the liquid forbids its free consumption, is often hurtful.
Gerard attributes the affection to constant stabulation. This, however, has a beneficial as well as a deleterious side. It undermines the health and vigor, and through lack of tone favors gastric torpor and impaction, but it also secures ample leisure for rumination, which is so essential to the integrity of the rumen and favors the onward passage of its contents. With dry feeding and a restricted water supply it cannot be too much condemned, but with succulent food and abundance of water the alleged danger is reduced to the minimum.
Active work and over exertion of all kinds must be admitted as a factor. At slow work the ox can still ruminate, but in rapid work or under heavy draft this is impossible, and the contained liquids may pass over from rumen to manifolds conducing to impaction of the former, or fermentations may take place, swelling up the mass of ingesta and distending the walls of the first stomach. Similarly, cattle and sheep that are hurried off on a rapid march with full stomachs are greatly exposed to both tympany and impaction.
In speaking of dry, fibrous food and lack of water as factors, we must avoid the error of supposing that succulent or aqueous food is a sure preventive. In a catarrhal condition of the rumen or in a state of debility, impaction may readily occur from the excessive ingestion of luscious grass, wheat bran, potatoes, apples, turnips, beets, or cabbage.
Finally defects in the anterior part of the alimentary tract may tend to impaction. Salivary fistula or calculus cutting off the normal supply of liquid necessary for rumination, tends to retention and engorgement. Diseased teeth and jaws interfering with both the primary and secondary mastication has the same vicious tendency. Old cows, oxen and sheep in which the molar teeth are largely worn out, suffer in the same way, especially when put up to fatten or otherwise heavily fed. In this case there is the gastric debility of old age as an additional inimical feature.
Symptoms. These vary with the quantity and kind of ingesta also to some extent with the previous condition of the rumen, sound or diseased. They usually set in more slowly than in tympany. On the whole the disease appears to be more common in the stable than at pasture. The animal neither feeds nor ruminates, stands back from the manger, becomes dull, with anxious expression of the face, arching of the back and occasional moaning especially if made to move. The abdomen is distended but especially on the left side, which however hangs more downward and outward and tends less to rise above the level of the hip bone than in tympany. If it does rise above the ilium this is due to gas and it is then elastic, resilient and resonant on percussion at that point. The great mass, and usually the whole of the paunch is nonresonant when percussed, retains the imprint of the fingers when pressed, and gives the sensation of a mass of dough. The hand applied on the region of the paunch fails to detect the indication of movements which characterize the healthy organ. The ear applied misses the normal friction sound, but detects a crepitant sound due to the evolution of bubbles of gas from the fermenting mass. This is especially loud if the impaction is one of green food or potatoes, even though the gas remains as bubbles throughout the entire fermenting mass, instead of separating to form a gaseous area beneath the lumbar transverse processes.
The respiration is hurried, labored and accompanied with a moan, the visible mucosæ are congested, the eyes are protruded and glassy from dilatation of the pupils, the feet are propped outward, and the head extended on the neck. There may be signs of dull colicy pains, movements of the tail and shifting of the hind feet, in some cases the patient may even lie down but never remains long recumbent. There may be occasional passages of semi-liquid manure, though usually the bowels are torpid and neither passages nor rumbling sounds on the right side can be detected. When moved the animal usually grunts or moans at each step, and especially when going down hill, owing to the concussion of the stomach on the diaphragm. In cases due to green food the irritation may extend to the fourth stomach and intestines and a crapulous diarrhœa may ensue. The temperature remains normal as a rule. The disease is more protracted than tympany, yet after several hours of suffering and continual aggravation the dullness may merge into stupor, the mucosæ become cyanotic and death ensues from shock, asphyxia, or apoplexy.
Course. Termination. Many cases recover in connection with a restoration of the contractions of the rumen, the eructation of gas, in some rare cases vomiting or spasmodic rejection of quantities of the ingesta, and the passage of gas by the bowels. This may be associated with a watery diarrhœa, and loud rumbling of the right side, which may continue for twenty-four hours or longer. With the subsidence of the diarrhœa there comes a return of health, or there may remain slight fever, inappetence, suspended or impaired rumination, dullness, listlessness, and a mucous film on the fæces. This indicates some remaining gastro-enteritis.
In some instances there is rupture of the diaphragm with marked increase in the abdominal pain and the difficulty of breathing. In others there is a laceration of the inner and middle coats of the rumen so that the gas diffuses under the peritoneum and may even be betrayed by an emphysematous extravasation under the skin.
Diagnosis. From tympany this is easily distinguished by the general dullness on percussion, the persistence of the indentation caused by pressure, the outward and downward rather than the upward extension of the swelling, and the slower development of the affection.
It is far more likely to be confounded with pneumonia, which it resembles in the hurried, labored breathing, the moans emitted in expiration, in the dullness on percussion over the posterior part of the chest, it may be even forward to the shoulders, and in the cyanotic state of the mucosæ. The distinction is easily made by the absence of hyperthermia, and of crepitation along the margins of the nonresonant areas in the lungs, by the fact that the area of chest dullness covers the whole posterior part of the thorax to a given oblique line, and by the history of the case and the manifest symptoms of overloaded stomach, not with gas but with solids. From gastro-intestinal catarrh it may be distinguished by the more rapid advance of the symptoms and by the absence of the slight fever which characterizes the latter.
Treatment. Slight cases may be treated by hygienic measures only. Walking the animal uphill, injections of cold water, friction on the left side of the abdomen to rouse the rumen to activity, antiseptics as in tympany to check further fermentation, and stimulants to overcome the nervous and muscular torpor, may be employed separately or conjointly. When it can be availed of, a rubber hose may be wound round the abdomen and a current of cold water forced through it.
When further measures are demanded we should evacuate any gas through the probang or a cannula, as in tympany, and thus relieve tension and then resort to stimulants and purgatives. Common salt 1 ℔. is of value in checking fermentation, and may be added to 1 ℔. Glauber salts in four or five quarts of warm water. A drachm of strong aqua ammonia or 2 oz. oil of turpentine and ½ drachm of nux vomica may be added. Bouley advocated tartar emetic (2 to 3 drachms), and Lafosse ipecacuan (1 oz. of the wine) to rouse the walls of the rumen, and more recently pilocarpin (ox 3 grs.), eserine (ox 2 grs.) and barium chloride (ox 15 grs.), have offered themselves for this purpose. The three last have the advantage of adaptability to hypodermic use, and prompt action. The repetition of stimulants and nux vomica may be continued while there appears any prospect of restoring the normal functions of the paunch, and when all other measures fail the only hope lies in rumenotomy.
Rumenotomy. The warrant for this operation is found in the entire lack of movement in the rumen, the absence of eructation, the cessation of rumbling and motion of the bowels, and the deepening of the stupor in which the patient is plunged. The longer the delay and the deeper the stupor and prostration the less the likelihood of a successful issue from the operation. The animal is made to stand with its right side against a wall, and its nose held by the fingers or bulldog forceps. If judged necessary a rope may be passed from a ring in the wall in front of the shoulder around the animal to another ring behind the thigh and held tight. Or a strong bar with a fulcrum in front, may be pressed against the left side of the body, and well down so as to keep the right side fast against the wall. A line may be clipped from the point of election for puncture in tympany down for a distance of six inches. A sharp pointed knife is now plunged through the walls of the abdomen and rumen in the upper part of this line, and is slowly withdrawn, cutting downward and outward until the opening is large enough to admit the hand. The lips of the wound in the overdistended stomach will now bulge out through to the wound in the abdominal walls, and three stitches on each side may be taken through these structures to prevent displacement as the stomach is emptied and rendered more flaccid. A cloth wrung out of a mercuric chloride solution may be laid in the lower part of the wound to guard against any escape of liquid into the peritoneal cavity. The contents may now be removed with the hand, until the organ has been left but moderately full. Two or three stable bucketfuls are usually taken, but it is by no means necessary nor desirable that the rumen be left empty, as a moderate amount of food is requisite to ensure its functional activity. As a rule at least fifty pounds should be left. Before closing the wound and especially in cases due to dry feeding, it is well in a tolerably large animal to introduce the hand through the demicanal to ascertain if impactions exist in the third stomach and to break up these so far as they can be reached. This done, the edges of the wound in the stomach are to be carefully cleansed, washed with the mercuric chloride solution and sewed together with carbolated catgut, care being taken to turn the mucosa inward and to retain the muscular and peritoneal layers in close contact with each other. It will usually be convenient to cut first the two lower stitches through the abdominal walls, and suture from below upward. When finished the peritoneal surface of the gastric wound may be again sponged with the mercuric chloride solution, together with the edges of the wound in the abdominal walls. Finally the abdominal wound is sutured, the stitches including the skin only or the muscular tissues as well. The smooth surface of the paunch acts as an internal pad and support, and with due care as to cleanliness, antisepsis and accuracy of stitching, it is rare to find any drawback to continuous and perfect healing. It is well to restrict the animal for three days to well boiled gruels, and for ten days to soft mashes in very moderate amount lest the wound in the paunch should be fatally burst open before a solid union has been effected.