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are removed, will look like ordinary flesh, save in cases of long duration, when of course the animal will be wasted. There is reasonable doubt whether the flesh of animals suffering from pleuro-pneumonia is hurtful; the existing evidence is rather to the effect that it has been consumed by large populations without injury. Nevertheless it should be an offence to sell the carcases of animals which have died from or suffered from this disease as if from a healthy animal.

From what has been said it is obvious that, save the organs of the chest be inspected, there is no chance of detecting the facts after death, although from noting that the pleura has been stripped off there may be a well grounded suspicion that something was wrong.

(471) Cattle Plague.

Cattle plague is occasionally epizootic in the British Islands. It is a highly contagious malady attended with diarrhoea, injection of the mucous membrane, and is accompanied by an eruption. The post-mortem signs in mild cases are not marked. There will be found congestion and ecchymoses in the gastro-intestinal mucous membrane, especially on the free borders of the mucous folds in the fourth compartment of the stomach and around the pylorus. In severe cases the alterations in the intestines and stomach are more profound. Not alone congestion of the entire surface but hæmorrhages, extravasations of blood and ulcers are to be seen. Sometimes there are extensive excoriations from the shedding of the epithelial layers of the mucous membrane. There is injection of the trachea and bronchi in the worst cases; here again the epithelial layer may have been shed, leaving excoriations. The lungs are often emphysematous, the heart is usually flabby and friable, the blood is dark coloured and coagulates imperfectly. The skin may be found in parts desquamating, in parts covered with pustules or papules. In mild cases the meat apart from the internal organs will not look different from any other meat, on the other hand in severe cases the meat itself will be dark coloured and the muscular tissues soft. There is no difference of opinion that animals which have died of cattle plague are unfit for human food.

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(472) Tuberculosis.

Tuberculosis has been fully considered at page 462. The question as to whether an apparently local affection of the lung also affects the entire body has been now definitely answered in the affirmative, and the safest course is to consider tubercle always generalized, and to condemn the whole carcase for the slightest tuberculous taint; it would also be a just and sufficient ground to condemn any milk derived from a tuberculous cow or other animal as not fit for human food.

(473) Actinomycosis.

This is a somewhat common disease of cattle, and occasionally it has been found to be a cause of disease and death to man. Possibly it is more common both in animals and men than is believed, for the symptoms during life and the appearances after death may be readily mistaken for local and generalized tuberculosis or for those of septicemia.

The disease is caused by the "ray fungus" (actinomyces); this (see Fig. 54) parasite forms rosettes of club-shaped elements. They may be seen as little white or yellowish specks by the unaided eye. The method by which it gains access to the body is unknown, but presumably it is swallowed with the food, and then effects an entrance into the tissues. Once in the tissues a local inflammatory action is set up and a neoplasm is formed very similar in appearance to tubercle. Often these tubercle-like nodules break down and suppurate. In cattle there is a predilection for the disease to attack the lower jaw. It also invades the lung and sometimes the bones.

The lithographic plate (Plate IX.) contains a representation of specimens in the Museum of the Royal College of Surgeons, No. 2,274 and 2,274c. The specimens are from the tongue of an ox profoundly affected with actinomycosis. The tongue was much enlarged, protruding four or five inches from the mouth. It is excessively hard and dense. The connective tissue is much increased, in the centre a great portion of the substance is converted into a pale and to the naked eye structureless medullary mass. There are several nodules, these are most numerous in the middle of the tongue, the size of the nodules varies from that of a bean to very

minute hardly distinguishable points. The nodules are for the most part aggregated in elongated masses, which are placed between the vertical muscular fibres. The transverse section shows well the white medullary growth.

The appearance of one of the tufts when examined by the microscope is delineated in Fig. 54. They are capable of cultiva

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tion in a nutrient medium, as, for instance, peptone-gelatin, and the disease may be propagated in animals by inoculation. The writer considers it the duty of the sanitary officers to condemn as unfit for human food an animal suffering from this disease; even although the malady is in appearance localized.

(474) Anthrax.

Anthrax is a rapidly fatal disease, killing numbers of oxen and sheep yearly in this and other countries; it is caused by the multiplication of a bacillus, the bacillus anthracis, within the body.

We have here only to deal with the post-mortem characteristics. A peculiar feature of anthracoid maladies is their tendency to putrefaction even before life is extinct. Immediately after death the body of the animal often becomes immensely swollen and deformed from a large development of gas. Everywhere in the subcutaneous tissue there are infiltrations of serum, the same infiltration extends between the muscles; the muscles themselves are of a dark red, violet, or black tint, and very friable. So that in a

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