Fig. 170.—Sessile form of intra-laryngeal polypus.
The prognosis of these tumours is grave, because death from asphyxia may occur during an attack of coughing or as a consequence of the fits of suffocation.
Treatment. As it is usually extremely difficult, if not impossible, to discover the exact nature of the tumour, medical treatment, except for instance in the case of actinomycosis, is of very uncertain value.
Surgical treatment alone suggests itself. Before attempting an operation tracheotomy should be performed and a metal canula inserted. The animal having been cast, and the upper laryngeal region anæsthetised by means of cocaine, a vertical incision is made in the median line below the larynx, passing through the skin, the vertical junction between the neck muscles and the three first circles of the trachea, and access is thus obtained to the larynx and subglottal region. The operation should only be performed in exceptional cases, such as that of a valuable stud animal.
Provided that the new growth has a well-developed pedicle it can be removed through the mouth by the use of an écraseur or simply by tearing out.
BRONCHITIS.
Diseases of the bronchi in bovine animals reveal very different characters, according to the nature of the primary cause, for which reason cases occur of simple acute bronchitis, verminous bronchitis, simple chronic bronchitis, pseudo-membranous bronchitis, tuberculous bronchitis, etc.
SIMPLE ACUTE BRONCHITIS.
Simple acute bronchitis co-exists with, or is often only the logical and inevitable complication of, coryza and acute laryngitis. It is commonly associated with inflammation of the mucous membrane of the trachea.
It accompanies cold and wet seasons, and usually appears with the autumn frosts, in animals still at grass. In animals under shelter it occurs after undue exertion followed by chills, and after sudden rain storms. It also attacks working oxen, which are much exposed to the weather.