CRYPTOGAMIC POISONING IN RUMINANTS.
Moulds and bacteria in brewer’s grains, or the marc of beet sugar or cider factories derange digestion, or cause abortion. Spoiled potatoes cause enteritis, vertigo, palsy, in sheep, nephritis and cystitis. Mouldy bread causes indigestion, urinary and nervous disorder. Mildew. Musty grain and fodder as in the horse. Ergot causes winter and spring gangrene of skin, feet, limbs, ears or tail, lethargy, palsy, spasms, delirium, abortion; variation in toxicity with stage and condition of growth, privation or liberal supply of water, or succulent vegetables. Symptoms: varying, mouldy bread causes digestive and urinary trouble, with marc or ensilage, develops slowly, impaired appetite, salivation, tympany, colic, diarrhœa, debility, paresis, spasms, delirium. Duration, 5 hours to 2 weeks. Gangrenous ergotism, necrotic sore, slough hard, dry, leathery, black, living parts at demarcation line pink or purple, puffed up, tender, necrosis involves all soft tissues and bone; nervous form: abortion form. Lesions: congestion of stomach, bowels, mesenteric glands, brain and meninges, petechiæ. Diagnosis, from anthrax, from coccidian hemorrhagic dysentery, from foot and mouth disease, from rinderpest. Prevention, stop or regulate the injurious fodder, salt and pack the fresh grains or marc. Treatment: antiferments, potassium iodide, saline purgatives, stimulants, oil of turpentine, injections, derivatives.
Causes. The growth of moulds on or in brewer’s grains, which have been preserved without salting and close packing, has at times rendered them dangerous poisons (Duvieusart, Wehenkel, Schütz). The refuse or marc of beet sugar factories, or of cider works may act in a similar manner. These products, at first neutral or only slightly acid, undergo an acid fermentation, with an abundant production of acetic, lactic or butyric acid which adds materially to their action in deranging digestion. These agents usually require a large amount to prove deleterious, about 150 to 200 lbs. a day. Arloing found three active microbian ferments in the pulp of the sugar factories, and four in that of the distilleries. The marc of apples has even caused abortion (Cornevin).
Spoiled potatoes have caused adynamic enteritis, with vertigo and paralysis (Zimmermann, Grabin, Holme) and in sheep symptoms of nephritis and cystitis as well (Kloss).
Mouldy bread has been found to cause indigestion and cerebral disturbances in cows (Cagny) or nervous disorders without digestive, urinary or febrile trouble (Fröhner, Martin and Varnell).
Mildew on the leaves of a grapevine has also poisoned six cows (Bisseauge).
Musty grain and fodder has the same general action as on the horse and produces paraplegia and other nervous disorders with or without digestive troubles.
The isaria fuciformis has caused the death of cattle which ate the grasses infested by it.
When we come to the ergots and smuts we find even more evidence of poisoning than in the horse. Toward the end of our long winters in the Northern States we occasionally find widespread gangrenous ergotism from eating infested hay, the lesions varying from simple sores around the top of the hoofs, in the interdigital spaces or on the teats and mouth, to loosening of part of the sole or wall, shedding of the entire hoof or sloughing of the entire limb—just above the hoof, at the fetlock, or in the metatarsal region. Portions of the tail or ears will similarly slough. This appears to be mainly due to the lessening of the calibre of the capillaries by contraction of their walls, under the action of the ergotin and secalin, seconded by the cold of the season. Cold is, however, by no means essential to its production. The other most common form of ergotism is the action on the nervous system. The contraction of the cerebral capillaries and disturbance of the circulation lead in some cases to a condition of lethargy and apathy in which the animal fails to eat or ruminate and gradually falls into marasmus, or paralysis may be induced, or delirium and spasms. Then finally there is the familiar form of abortion induced apparently by the contraction of the involuntary muscles of the womb and of its capillary vessels.
There is, however, a great difference of opinion as to the deleterious action of ergot. Various experiments with large doses of ergot on pregnant animals have failed to produce any sign of abortion. The agent, however, varies in its nature according to the conditions under which it grew and the stage at which it was collected, so that the failure to produce the expected result in a given case can by no means be accepted as disproving its pathogenic properties under other conditions.
The same remarks apply largely to the action of the smuts, which are often eaten in large quantities with impunity, especially if plenty of water or succulent vegetables are allowed, whereas under other conditions as in winter, under the action of cold, with the usual water supply frozen up, and no succulent food, it proves very destructive.
Symptoms. These vary with the particular poison: With mouldy bread the symptoms may come on promptly with indigestion, tympany, constipation, marked irritation of the urinary organs, and it may be nervous disorder. Sometimes, as noted above, the narcotic action is shown with paresis or paralysis and stupor without any manifest disorder on the part of the digestive or urinary functions.
Most commonly with mouldy fodders, grains, marc, or ensilage the results are tardily developed and only after long continued use of the spoiled food. There is then loss of appetite, and rumination, drivelling of saliva, some tympany, and abdominal pain shown by frequent movement of the hind limbs, lying down and rising. The bowels may be costive at first, but this early gives place to a fœtid diarrhœa, with weak rapid pulse (100 per minute) palpitations and hurried breathing. The walk becomes weak, unsteady, staggering or stumbling, and there may appear marked paresis especially of the hind parts. When nervous excitement sets in there may be twitching of the muscles of the neck, shoulders or thigh; the eye rolls or becomes fixed and the pupils are dilated; the muscles of the face are contracted and the jaws clinched, with grinding of the teeth. Bellowing or pushing of the teeth and nose, the forehead or horns against the wall or other obstacles, or the dashing violently against obstacles is occasionally observed, and indicates in most cases an unfavorable termination.
The duration of the malady is uncertain. It may not be over five or six hours in acute cerebral cases, and especially in sheep, and again it may be prolonged for one or two weeks. Death often takes place in convulsions.
In gangrenous ergotism a necrotic sore with more or less surrounding swelling may be seen, and a line of demarcation forms of a pink or purplish aspect along which the separation of the dead tissue takes place. The slough is usually of a dark red or black color, the red globules having apparently migrated into the tissues and piled up in the capillaries in the early stages of stagnation. When the line of separation is higher, the line of demarcation completely encircles the limb, the inflammation and swelling is very marked just above this line, the skin and soft tissues beneath drying and withering up into a dark red leathery mass, and this is gradually separated by the formation of a granulating surface above. The process of separation takes place much more slowly through the bony tissues, and not unfrequently the soft tissues having become detached, the lower part of the limb is separated at the first joint below the line of demarcation and the bone from that line down to its free end remains as a projecting necrosed stump. In the ear or tail the necrotic portion withers up into a stiff rigid shrunken slough which becomes detached sooner or later by mechanical violence.
In the nervous ergotism the symptoms are largely those of the adynamia, paresis and convulsions already described.
In abortion from ergotism there are usually few premonitory symptoms, and the occurrence is to be explained by the number of victims in a herd eating ergot or smut.
Lesions. These vary greatly. Usually the congestion and inflammation are most prominent in the abomasum and small intestine, complicated by ecchymosis and even extravasation which may so thicken the mucosa as to block the intestine (Walley). The mesenteric glands are usually gorged with blood and of a deep red. The brain may be nearly normal or violently congested and with its meninges covered with petechiæ.
Diagnosis. From anthrax this affection is distinguished by the absence of the specific large bacillus in the blood and of the marked enlargement of the spleen, by the great prominence of the nervous symptoms in many cases, and by the history of a dietetic cause.
From the coccidian hemorrhagic dysentery it is diagnosed by the absence of the coccidia in the stools and the predominance of the nervous systems.
From foot and mouth disease, the gangrenous ergotism is distinguished by the facts that the sores are in the nature of sloughs, and not vesicles, and that some members of the herd are almost certain to show sloughing of the limb at some distance above the hoof. More important still is the fact that the daintily feeding sheep and the pig kept in the same yards do not suffer from the ergotism.
From rinderpest it is differentiated by the fact that the sores on the mouth (when present) are not of the nature of epithelial concretions, and they do not appear on the vulva, and more significant still there is no indication of the introduction of the disease by contagion nor of its rapid progress from herd to herd. The immunity of sheep from gangrenous ergotism is another significant feature.
Prevention consists in putting a stop to the supply of the altered food or, if it must be given, in giving it in small quantities only with abundance of water or fresh succulent aliment. In the case of grains or marcs the fermentation may be checked by adding ¼ per cent. of common salt and packing the material firmly in a close box or silo.
In ergotism, succulent food, water ad libitum, stimulants, poultices, fomentations or wet bandages, a warm building and pure air are all important. Usually ergot and smut can be safely fed in relatively large amount with a liberal ration of potatoes, turnips, beets, green food or ensilage.
Treatment does not differ materially from that advised for the horse. Antiferments including potassium iodide, and saline purgatives stand at the head of the list. Stimulants may be demanded to rouse the torpid bowels and nervous system and unless contraindicated by gastro-intestinal inflammation oil of turpentine offers itself as at once stimulant, antiseptic and eliminating. Injections and counter-irritants are of use. Then cold (ice, snow, water) to the head, and the confinement of the patient so that he cannot injure himself or others are not to be neglected.