Gadfly is a name commonly applied to various insects, a large number of which belong to the great Linnaean genus OEstrus, while others belong to the genusTabanus. OEstrus bovis or ox gadfly (the Hypoderma bovis of some naturalists) is about 7 lines in length with a yellow thorax, with a black band; white abdomen; fulvous terminal segments and dusky wings. This species attacks the horse also, the female depositing her eggs in the skin of these animals in considerable numbers. In a short time the eggs are matured, and produce a larva or worm, which immediately pierces the skin, raising large lumps or tumours filled with pus, upon which the larva feeds.
Oestrus equi (the Gastrophilus or Gastrus equi of some naturalists) deposits its eggs upon such parts of the skin of horses as are subject to be much licked by the animal, and thus they are conveyed to the stomach, where the heat speedily hatches the larvae, well known under the name of botts.
Oestrus ovis (also called Cephalomyia ovis) deposits its eggs in the nostrils of sheep, where the larva is hatched, and immediately ascends into the frontal sinuses, attaching itself very firmly to the lining membrane by means of two strong hooks situated at its mouth. Other species infest the buffalo, camel, stag, etc. Even rhinoceroses and elephants are said not to be altogether exempt from their attacks.
The characteristics of the genusTabanus are two enormous eyes, usually of a greenish-yellow colour rayed or spotted with purple, antennas scarcely longer than the head, the last joint with five divisions. These insects suck the blood of horned cattle, horses, and sometimes people. The Tabanus bovinus, or larger gadfly is common in Europe. It is about 25 mm long, brown above and grey below. Its larva live on the ground, and its metamorphosis takes place under the earth but close to the surface. Research Gadfly
An abscess is any collection of purulent matter or pus formed in some tissue or organ of the body, and confined within some circumscribed area, of varying size, but always painful and often dangerous. Research Abscess
Empyema is a pathological term describing a collection of pus in a cavity, especially applied to pus in the pleural cavity of the lung. Research Empyema
Empyema thoracis is the condition of pusformation in the pleural space. The pleural effusion which accompanies infective conditions of the lung may itself become infected and form pus. A lung abscess may burst into the pleural space. Haemothorax may become infected. The symptoms which the condition produces depend on the amount of puspresent, and the degree of compression of, or disease in, the underlying lungs. There is some embarrassment of respiration, and 'swinging' fever, typically present whenever pus has accumulated in the body. Fever may sometimes be absent, especially if the patient is being treated with antibiotics. The patient with an empyema is severely toxic, looks ill, loses weight rapidly and becomes severely anaemic. If the pus is sufficiently thin to be removed through a needle, then the treatment is entirely by aspiration. Penicillin or other antibiotic solution may be injected into the pleural space after the withdrawal of the pus. Aspiration needs to be repeated daily until lung expansion is adequate. If the pus becomes too
thick for aspiration, the empyema is treated by one of two surgical methods: (a) A small intercostal incision is made and a large self- retaining catheter placed into the pleural space to allow the escape of pus. The catheter is connected to an under-water seal. This method of intercostal drainage is rarely used but it is sometimes suitable for children. (b) Rib resection and drainage by a wide-bore tube. Part of one rib is removed and the pleural space opened through its periosteum. This tube may be left open at its outer end or may be attached to an under-water seal. One type of tube is the 'Tudor- Edward' empyema tube which has an additional small rubber side tube through which the empyema cavity can be irrigated. Research Empyema Thoracis
Leucocytosis is the name given to a condition of the blood in which the leucocytes or white corpuscles in the bloodplasma are increased in number. These leucocytes are minute protoplasmic cells, which have the power of movement and can pass out of the smallest capillary blood vessels into the surrounding tissues. They act as scavengers, and play an important part in the destruction and removal of bacteria in the body, a process known as phagocytosis.
The leucocytes are of different types, and normal blood contains a fairly constant proportion of each type. In infection or inflammation the leucocytes become greatly increased in number; the leucocytes which are killed in the attack on the bacteria form pus. In certain blood diseases, of which leukaemia is the best example, the increase is also often enormous, even reaching to 80,000 and 100,000 white corpuscles in a cubic millimetre of blood which normally contains only from 5,000 to 6,000. The symptoms of this disease are very similar to those of anaemia, and the diagnosis is confirmed by microscopic examination of the blood. The leukaemias are accompanied by swelling of the glands but this also occurs in other diseases.
A small increase of the white corpuscles is found in such a great number of the more common diseases that an examination of the blood is often made as a routine measure. In many cases, for instance, of appendicitis, the white corpuscles increase to from 15,000 to 20,000 per cubic millimetre; in pneumonia they also increase sometimes to 40,000 per cubic millimetre. In other more common diseases such as tonsilitis or sore throat, erysipelas, in smallpox, and inflammatory diseases such as septicaemia, boils, bone diseases and pyaemia, a greater or less increase is always found. In other diseases absence of an increase often enables the right diagnosis to be made, since in typhoid fever (which might in the early stages be mistaken for appendicitis) there would be no increase in the early stage of the disease, but it would probably be marked in the latter stages. In whooping-cough a marked leucocytosis occurs, which may confirm a doubtful diagnosis. Research Leucocytosis
Abbreviations
Research Abscess
