MALIGNANT CATARRH OF CATTLE.
Local causes. Debilitation. Polluted air. Poor diet. Symptoms, gastro-intestinal, fever, lachrymation, turbid aqueous, photophobia, congestion of mucosæ, generally disturbed circulation, breathing, depression, heat of forehead, buccal petechiæ, epithelial desquamation, abrasions, ulcers, abortion, albuminuria, local swellings, shedding of horns, dropsy, dyspnœa. Lesions, in nasal mucosa, subcutem, cerebral, dark blood. Prognosis. Treatment, antiphlogistic, laxative, diuretic, tonic, locally steam, antiseptic, astringent, trephining.
This disease occurs chiefly in cold damp marshy localities where the vital power is impaired or in cold situations exposed to severe north and east winds. In the wet cold seasons of spring and autumn it is especially prevalent. According to Rychner it rarely attacks old cows but prevails among young cows and oxen. In the south of France on the contrary it appears chiefly in the hot season (June and July) and is attributed to suppressed transpiration. It prevails especially however in herds kept in small filthy stables, low in the roof, hot, close and badly aired. (Festal). In New York it appears in cattle on black muck pastures and in Minnesota on the dried up ponds.
Symptoms. Diarrhœa is a common premonitory symptom arising from the irritation of the intestinal canal as it is soon followed by some degree of costiveness, the dung becoming dark colored, firm and scanty. Diarrhœa reappears later. The coat stares or the beast actually shivers; the head is depressed; the roots of the horns and the forehead are hot; the eyes are sunken, swollen and red, suffused with tears, turbid in their anterior chamber (aqueous humor) and intolerant of light; The muzzle dry and hot; the mouth hot but moist with abundant saliva; the mucous membranes of the mouth, nose and vagina have a bluish red color; the pulse is rapid and more or less full or hard; impulse of the heart weak; the breathing is accelerated, the respiratory sound is heightened in intensity and a cough is frequent. Temperature 104° to 107° F. The urine is scanty and high colored. The surface of the body is alternately hot and cold, and after some time a watery fluid begins to distil from the nose.
At the end of twenty-four hours the symptoms are intensified or altered. The eyelids are more swollen and the flow of tears more profuse; the nasal discharge becomes slimy, and streaked with blood, and accumulations take place in the frontal sinuses as indicated by the increasing heat of the forehead and the dullness on percussion. In the mouth appear dark red spots, from blood extravasation, over which the epithelium sloughs off leaving raw unhealthy sores. The appetite entirely fails; dung and urine are passed painfully and with effort, and abortion frequently takes place in pregnant cows. The urine is albuminous with cell forms, and casts. The limbs appear rigid and it pains the animal to move.
From the fourth to the sixth day the ulceration appears on the mucous membrane of the nose which has often a claret color, and the nasal discharge becomes again more watery and irritating. The muzzle is swollen and a dropsical infiltration appears beneath the jaws which extends along the neck to beneath the thorax and into the limbs. Portions of the nasal mucous membrane now slough off, and similar sloughs are often seen on the skin of different parts of the body; the secreting structures of the horns and hoofs even participating so that these are easily detached or shed. Saliva flows profusely from the lips, a fetid watery diarrhœa succeeds the constipation, the dropsy becomes nearly general and death occurs on the eighth, ninth or tenth day of the illness. Convulsions and symptoms of suffocation may precede death.
In a post mortem section the principal lesions are found in the nasal cavities and skin. The areolar tissue in both is the seat of an abundant serous infiltration, which has taken place into the deeper layers of the skin as well, rendering it thick, hard and unyielding. Besides the sloughs and ulcerations on the skin and mucous membranes, false membranes have been met with, on the lining membrane of the mouth and air passages. The ulcers in the nose have in many cases reached the bone, and from the abundant infiltration and softening, the membrane is easily stripped from the walls of this cavity and of the sinuses. The general infiltration appears to have reached the brain, which is described as softened and having an undue amount of liquid in its cavities. The blood contained in the vessels is dark colored and numerous patches of extravasation are visible on the mucous and serous membranes as well as in the interior of organs.
Unless the malady can be controlled in its early stages it usually proves fatal. Patients that recover after it has been well developed at times retain its effects in permanent blindness or palsy of the hind limbs.
Treatment. Early and vigorous antiphlogistic measures are strongly recommended by French and Italian veterinarians. Gellé and Ercolani advocate the most copious bleedings. Festal insists that all other measures are useless when this is neglected. Before adopting free sanguineous depletion the history of his practice was a record of deaths, whereas later his losses were in cases where from a failure to recognize the disease at the outset, from the existence of diarrhœa, from the patient being pregnant or from a fear that the milking properties might be impaired, bleeding was deferred. He pushed the bleeding to the extent of causing acceleration of pulse, quickened breathing and heaving of the flanks, to effect which sixteen pounds had to be abstracted on an average. If this were done early the engorgement of the muzzle had usually greatly diminished if not entirely disappeared in the course of seven or eight hours thereafter. The alleged benefit is probably largely due to elimination.
Less heroic treatment is now generally adopted. An active purgative (one and a half pounds Epsom salts) may be given even though apparently contraindicated by the premonitory diarrhœa, and a further useful derivation may be obtained by applying active friction or even stimulating embrocations to the legs.
Steam with or without sulphur dioxide may be inhaled as for ordinary coryza and cold water or ice kept applied to the forehead.
Nitre in ounce doses daily or liquor of the acetate of ammonia in three ounce doses may be given after the purging has ceased. Or drachm doses of hydrochloric acid with bitters may be given thrice a day in at least a pint of water.
Where the nasal discharge persists after the subsidence of the other symptoms the sinuse should be trephined in front of the horn, and tepid water and mild astringent and antiseptic lotions injected until a healthy action has been established. Change to a dry, well drained pasture or building is desirable for both treatment and prevention.