Part 60

OTHER SURGICAL OPERATIONS.

Descriptions of other surgical operations not given in this chapter may be found in other parts of this work by reference to the index.

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SURGICAL OPERATIONS.

DESCRIPTION OF PLATES.

Plate XXVI. Devices for casting cattle. (From Fleming.)

Fig. 1. Reuff's method of throwing or casting the ox.

Fig. 2. Miles's method of throwing or casting the ox.

Plate XXVII. Surgical instruments and sutures. (After Reynders and Fleming.)

Figs. 1 and 2. Seton needles. These may be either long or short, straight or curved, according to the locality in which a seton is to be inserted.

Fig. 3. Various forms of surgical needles.

Fig. 4. Suture forceps or needle holder, for passing needles through thick and dense tissues.

Fig. 5. Knot properly tied.

Figs. 6, 7, 8, 9, 10. Various forms of sutures. Fig. 6, interrupted suture; 7, quilled suture; 8, uninterrupted suture; 9, twisted suture, made by passing suture pins through the parts to be held together and winding the thread about them so as to represent the figure 8; 10, single-pin suture.

Fig. 11. Appliance for ringing the bull, one-fourth natural size.

Fig. 12. Nose clamp, with spring and keeper.

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TUMORS AFFECTING CATTLE.

By JOHN R. MOHLER, V. M. D.,

Chief, Bureau of Animal Industry.

Definition.--Tumors are abnormal masses of tissue, noninflammatory and independent in character, arising, without obvious cause, from cells of preexistent tissue, possessing no physiologic function, and characteristically unrestrained in growth and structure.

Tumors are abnormal masses of tissue. The application of the term "tumor" is directly connected with the fact that they produce local enlargement.

They are noninflammatory; that is, the process of inflammation is not directly the cause or accompaniment of them. An inflammatory new growth tends to disappear upon the subsidence of the inflammatory process, while spontaneous disappearance of a tumor is comparatively rare.

Tumors are independent. For instance, their nutrition bears no relation to the nutrition of the body. A lipoma, or fatty tumor, in the subcutaneous tissue, may go on increasing to huge bulk while the body is steadily emaciating. Again, the tissues of the aged gradually undergo atrophy, yet cancers arise at this time and grow rapidly.

Tumors are unrestrained in growth and structure. In the development of an animal we know at what period of its existence the mass of tissue called liver will develop--what its site, structure, and size will be. We know that it will remain only in that locality, and not, as it were, colonize throughout the system. With tumors it is different; there are no laws by which we can forecast the time, place, nature, or size of development of them. There is no cartilage in the kidney or parotid gland, yet a chondroma, or cartilage tumor, may develop in either. Even when a new growth of tissue is started by an injury and consequent inflammation--as, for instance, proud flesh--there is a limitation of its size, but the controlling influences which govern the size of an organ or normal mass of tissue and limit the extent of an inflammatory overgrowth are all absent in the case of tumors. They are unrestrained, lawless.

Metastasis expresses the lawlessness of tumors as regards being limited to the original site of development. Small particles of tumors enter the blood vessels or lymph streams and are carried to distant parts of the body, where they lodge and start new tumor formations. Expansion by colonization in this manner is a rule with many tumors, and, since they exercise no function of use to the organism, this dissemination of actively growing particles becomes a menace to the system by numerically increasing the body's burden, opening new channels of drain upon the system and adding new centers for the absorption of putrefactive materials when the secondary tumors shall have degenerated. It is this which makes metastasis such an important element in the malignancy of tumors.

Tumors possess no physiological function. They are absolutely useless. Fibrous tumors bind no parts of the organism together; bony tumors add nothing to the supporting framework of the body; the tissue of fatty tumors never serves as a storehouse of feed and energy; the cells of an adenoma, or gland tumor, furnish no secretion; a tumor composed of muscle tissue produces no increase to the strength of the individual--its muscle cells are not contractile.

Tumors arise from cells of preexistent tissue. Tumor tissue is not a new variety. Whatever the structure of a tumor, its counterpart is found among the tissues of the body, the lawlessness of the tumor, however, showing itself in more or less departure from the normal type. This departure is usually a reversion to a more elementary or embryonic stage, so that the tumor tissues may be said to be structurally immature.