Development. Leuckart found that the adult Pentastomata copulate in the nasal chambers, as many as half a million of eggs being fertilized in a single female; that these eggs are discharged with the nasal mucus and falling on vegetables are taken in by herbivora; their shells are digested and destroyed in the stomach, and the liberated embryos perforate the intestinal walls and encyst themselves in various organs. The encysted embryo varies from ¹⁄₅₀₀ to ¹⁄₄₀ inch in length, is rounded and blunt anteriorly but very thin posteriorly with the tail slightly curved toward the ventral aspect. It is several months before the feet, cutaneous spine and generative organs are developed, and during this period it undergoes several moultings. Finally it leaves its cyst and may live free in the cavities in the body of its host, and if it does not escape from the body it finally constructs a new cyst and then dies. If the host is eaten by a carnivorous animal the liberated pentastomata reach the nose either from the lips or pharynx and in a few months more acquire their complete development. They must reach the nose of the horse by their presence in the food or water.
Symptoms Caused by the Pentastoma. No morbid symptoms have been traced to the young encysted condition of the parasite. Yet it would not be surprising if their presence in large numbers in the mesenteric glands and liver should give rise to troubles of assimilation, sanguification, biliary secretion and the like. Frerichs says they are more common in the human liver in Germany than echinococcus, but adds that they have no clinical importance.
In their mature condition however they cause considerable irritation and nasal discharge when present in large numbers. In dogs there is running from the nose the discharge containing an abundance of the ova, restless, fretful habits, sometimes a morbid readiness to bite, frequent shaking of the head and rubbing of the face.
The treatment would be to trephine the sinuses and inject lotions impregnated with creosote, carbolic acid or naphtha. From the danger to man of becoming infested it is important to ascertain the true nature of any nasal discharge of the dog especially in countries like Germany and Egypt in which this parasite is common.
Prevention. Deny raw offal of herbivora to dogs.
AFFECTIONS OF THE THROAT.
Sore throat, Angina, Cynanche—is a generic name applied to a series of inflammatory affections of the various structures about the throat. If the larynx is specially inflamed the disease is known as laryngitis, if the pharynx, as pharyngitis, if there are exudations forming false membranes it is croupous or diphtheritic, or if associated with some general febrile affection, it takes its name accordingly, influenza, strangles, distemper, or scarlatina, as the case may be.
LARYNGITIS IN THE HORSE.
ANGINA LARYNGITIS, CYNANCHE LARYNGEA, ETC.
Causes, mechanical, cold, irritants, extension, diet, close stables, infectious disease. Symptoms of acute form, head extended, throat swollen, tender larynx, cough, in early stage, after exudation, wheezing in inspiration, dysphagia, fever, œdena glottidis, spasms, dyspnœa, successive discharges. Lesions, tumefaction, softening, friability, redness (ramified or not), erosions of mucosa, œdema. Course, duration, sequelæ, cough, roaring. Subacute form, chronic form, in old debilitated animals, in those reined too tightly, in those which perspire with difficulty or bear heavy coats. Symptoms, local, in breathing, cough, effect of cold air, or water or of dust. Sequelæ, ossified cartilages, roaring, emphysema, bronchiectasis. Treatment, hygienic, soothing, sheepskin, compress, poultice, mustard, sulphur dioxide, laxative, neutral salts, expectorant, sedative, derivative, tracheotomy, with trochar and cannula, with scalpel, tracheotomy tubes. Insufflation, injection. In chronic laryngitis, electuaries, mustard, derivatives, astringents, caustics, tonic inhalations.