An inflammation seated in the lining membrane of the larger bronchial tabes constitutes the disease called bronchitis, a very common affection among dogs. It is generally ushered in by an inflammation of the mucous membrane of the nasal passages, which commencing in the nostrils travels downward to the lungs.

The disease may be divided into two stages, which can be conveniently termed the dry and the moist. From the occurrence of the first symptoms in the nose, in from one to three days the disease makes the transit to the larger bronchial tubes, the mucous membrane of which becomes dry, reddened, swollen, and sensitive. In the progress of the affection, after two or three days, the mucous secretion, which has been absent or scanty, reappears and is abnormally increased.

Bronchitis may be primary or secondary, that is it may occur as a distinct affection or be developed as a complication of certain diseases, such as pneumonia, or consumption.

It may be either acute, sub-acute, or chronic, as based on the differences as regards the severity and duration of the inflammation.

Causation

Exposure to damp and cold; violent exercise, and subsequent confinement in draughty kennels; changes in the weather, and some special atmospheric influence not understood. This is to be inferred when the disease prevails as an epidemic.

Symptoms

Shivering, and the common evidences of catarrh, are the primary symptoms noted, followed by some fever, higher pulse, thirst, loss of appetite, dulness and general lassitude. The cough is at first dry and painful, but not suppressed. This changes as the mucous secretion becomes abundant, then the pain abates, the cough loosens and has a softer tone. Respiration is usually unaffected, rapid breathing being observed only in exceptional cases, in which the mucous secretions accumulate, and obstruct the bronchial tubes. The expectoration is at first small and scanty, later copious and frothy. The eyes are reddened, the nose hot, and glued with a thick mucus which becoming free and thin, is accompanied with frequent sneezing.

These symptoms are present in ordinary bronchitis. An unfrequent and graver form is developed when the inflammation affects the smaller tubes. This is termed capillary bronchitis, and differs widely from the ordinary acute disease. It is an exceedingly grave affection, and the dangerproceeds from obstruction to the current of air to and from the air-cells. This obstruction is due to the small size of the affected tubes. The swelling of the mucous membrane, and the presence of the muco-purulent liquid, which in the larger tubes do not interrupt the free passage of air during respiration, here occasions serious interference. In the capillary form of bronchitis, all the symptoms of suffocation are present and death usually results from that cause.

Diagnosis

Acute bronchitis is to be discriminated from pleurisy and pneumonia, more especially the latter. The absence of severe pain and rapid breathing, the presence of a copious expectoration, which is not rusty, are negative points, which, with an examination of the chest, will render a diagnosis easy.

On percussion nothing abnormal is detected. On auscultation coarse mucous rattles are heard throughout the chest. Their presence and diffusion over both sides are distinctive of the disease. The gravity of the symptoms will indicate whether capillary or simple acute bronchitis is present.

Prognosis

Ordinary bronchitis when unassociated with other diseases is dangerous only in very young puppies and old dogs. A mild attack is soon recovered from. In the capillary form, there is little or no hope for the animal so affected.

Treatment

A very important item is to guard against changes in the temperature. The patient should be kept in a room well ventilated and comfortably heated. In the earlier stage, an attempt should be made to abort the disease, with from five to ten grains of Dover's powder at night, and an application of mustard and vinegar, or kerosene oil to the chest, anointing the parts afterwards with fresh lard. This treatment should be followed the next morning with a dose of castor oil or syrup of buckthorn.

The effort if unsuccessful will at least lessen the severity of the disease. For the cough in the earlier stage the following is recommended -

℞ Syr. Scillae ℥ i.

Spts. AEth. Comp. ℥ i Syr. Tolu ℥ ij.

Ft. Mist. Sig. Dose one teaspoonful every three or four hours.

If the cough becomes a distressing symptom, opium can be wisely combined with expectorant remedies, as in the following -

℞ Sol. Morph. Sulph. Syr. Scilla Vini Ipecac Syr. Senegas aa ℥ i Ft. Mist. Sig. Dose one teaspoonful every three or four hours.

In the second stage, nutritious diet and tonic remedies are measures which assist in recovery; two grains of quinine may wisely be given two or three times a day.

The chlorate of potassa is a remedy of great value in all diseases of the mucous membranes, more especially when the secretions are scanty- It will be found effacacious in all stages of bronchitis, and may be added freely to the water the animal drinks, or given in the following mixture -

℞ Potass. Chloratis ℥ ij Syr. Scillae ℥.

Syr. Tolu. ℥ ij.

Aquae ad. ℥ iv.

Ft. Mist. Sig. Dose one teaspoonful every three or four hours.

If the disease involves the smaller bronchial tubes, and suffocation is threatened, an emetic should be administered and a stimulating expecto-rant given as in the following -

℞ Ammonias Carb. ℥ ij Syr. Senega) ℥ iij.

Ft. Mist. Sig. Dose one half a teaspoonful in a tablespoonful of peppermint water every two hours.

When danger of sinking is evident, whiskey or brandy may be added to the treatment and given in dessertspoonful doses, as often as the urgency demands.

If the disease tends to pass into the chronic form, cod liver oil two or three times a day should be given, with an iron tonic of elixir calisaya bark, iron, and bismuth, dose one teaspoonful.

As a rule expectorant remedies are not indicated in chronic bronchitis, and do harm by their depressing effect, and by disturbing the appetite and digestion.