Under this head will be considered simple inflammation of the nasal mucous membrane. This disease might be considered as a mild febrile affection with the local manifestation in the nose, but it is more convenient to treat of it here as a malady of the nasal chambers.
CORYZA IN THE HORSE.
The chief causes are exposure to wet and cold and especially when the subject is exhausted and the skin relaxed and covered with perspiration. In these circumstances a piercing wind, a cold drizzling rain, or a draught in the stable is particularly dangerous. Sudden alternations of temperature and especially a change to a warm stable when the general effect is aggravated by the impurity of the atmosphere and the irritant emanations from dung and urine. Damp climates are more injurious than those that are clear, dry, and bracing, and so are equally damp stables whether the moisture is due to the nature of the soil, such as a cold impervious and undrained clay, or of the building which, from its newness, may retain a dangerous amount of moisture in the plaster, or because of the hygroscopic properties of the building materials which draw moisture from the surrounding soil. It mainly attacks young horses after they have passed out of the hands of the breeder or dealer, and have been placed in new conditions of life alike as regards feeding, stabling and work. Old and ill-conditioned animals are more susceptible than the strong and vigorous, and the changes of the coat in spring and autumn prove strong predisposing causes. Nervous causes are potent in causing engorgement of the erectile tissue covering the turbinated bones, and local irritants, like septic dust, lime, ipecacuanha, pollen of certain plants, smoke, and irritating fogs may precipitate it. Iodine in large doses produces temporary catarrh. The weakness of the mucosa from a previous attack predisposes to a second. Occasionally the disease sweeps over a country, assuming the form of an epizootic when it may perhaps be preferably considered as a catarrhal fever, strangles or mild type of influenza, which see.
Symptoms. In the milder forms of coryza the symptoms may be almost exclusively local, consisting in redness and dryness of the membrane lining the nose and sneezing, soon followed by the bilateral discharge of a thin transparent watery liquid, succeeded by a turbid flow (epithelial cells in excess) and after two or three days by a thick, white, flocculent, puriform fluid (suppuration diapedesis). With the supervention of the purulent discharge, comes an abatement of the local inflammation and the freer the discharge the greater usually is the relief obtained and the more rapid the recovery. The eyes are usually red and watery and sometimes the eyelids are swollen. This implies the continuity of the inflammation through the lachrymo-nasal duct, and the obstruction to the flow of tears into the nose.
When constitutional disturbance exists a rough or staring coat appears as one of the first symptoms, the sneezing is more violent, the nasal mucous membrane is more reddened and swollen, the eyes more dull, sunken and watery, the mouth hot and clammy, the temperature of the body raised, the pulse more frequent and having a sharper beat, the impulse of the heart may often be felt by applying the hand to the chest just behind the left elbow, the appetite is fastidious and the secretions of the bowels and kidneys are diminished, the latter being denser and more highly colored, from the absorption of irritating or infecting matters the glands under the throat are swollen and the swelling of the mucous membrane may be such as to impair breathing and even to threaten suffocation. In severe cases in which the inflammation extends to the nasal sinuses there is heat and tenderness over the forehead and the pain and weight are manifested by the pendent head and the red sunken, watery eyes and tumefied eyelids. When it extends to the throat, the cough, the difficulty in swallowing and the local tenderness on handling are characteristic.
Course. With the occurrence of suppuration, improvement commences and if the inflammation does not extend beyond the nasal chambers, and if it is not kept up by a repetition or continuance of the cause the disease will have terminated in recovery in eight or ten days. For ulterior consequences in bad cases see chronic catarrh, conjunctivitis, abscess of the nasal sinuses, laryngitis, stomatitis, staphylitis.
Treatment. In slight cases the simplest treatment only is required. Place the animal in a dry, airy, loose box, clear of draughts, and with uniform temperature of 55° to 60° Fah., if obtainable. In the cold season blanket warmly, and hand-rub and loosely flannel bandage the legs. Feed on sloppy bran mashes only and add half an ounce to an ounce of powdered nitrate of potash daily. Give fresh water ad libitum, solicit the action of the bowels by giving injections of warm water three times a day, and encourage the nasal discharge by causing the patient to inhale steam for half an hour or an hour twice daily. This may be done by giving scalded bran in a nose-bag or by keeping the head over a bucket containing hay with boiling water poured over it, the steam being meanwhile directed by a bag open at both ends one of which is fixed around the animal’s nose and the other round the mouth of the bucket. As a local astringent, tonic and antiseptic the fumes of sulphur (burned behind the animal and no more concentrated than can be breathed with comfort) will do much to cut short the attack. It is more soothing if combined with steam. Shut doors and windows, add a few drops of alcohol to some pinches of sulphur and burn on paper laid on a clean shovel or piece of sheet iron. When enough has been used extinguish by covering with a cup or other object. Repeat several times a day. Under this treatment recovery may be completed in three or four days.
In severe cases attended with fever, besides the above a dose of laxative medicine may be given (three or four drachms of aloes), with this precaution, that if the fever is of a low type or the malady epizootic, half the dose only can be safely allowed (2 dr.) on account of the danger of superpurgation. The nostrils must be more assiduously steamed and linseed tea may advantageously replace fresh water as a beverage. If there is much swelling and tenderness of the glands a poultice should be applied to the throat and between the jaws, and sulphur fumes as advised above, or anodyne astringent insufflation powder may be resorted to. Morphia chlorate two grains, bismuth nitrate, six drachms and finely powdered gum arabic three drachms may be blown into the nostril during inspiration, or the astringent anodyne injection advised below for chronic catarrh may be used. Cocaine spray is often very helpful, or the same agent may be used in the liquid form on cotton wool inserted in the nasal chamber. If this is without effect a weak continuous current of electricity will cause constriction and give prompt relief. It may be repeated every few hours. In the absence of this the emanations from a weak solution of ammonia or from carbonate of ammonia may be used. In cases with excessive and persistent muco-purulent discharge, with presumptive infection from outside sources, or in the young, from the diseased maternal passages, insufflation with calomel, painting with a two grains to the ounce solution of nitrate of silver, or injection with some other germicide may be resorted to.
In case the fever is of a low type, liquor of the acetate of ammonia (4 ozs.), salammoniac (¼ oz.), or even carbonate of ammonia (½ oz.), may be given several times a day, with sweet spirits of nitre (½ oz.) and tincture of gentian (1 oz.) Alcoholic stimulants are often used. Inhalations of iodine and iodide of potassium with ether and chloroform are often successful.