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It will be seen from the above table that the rabbits inoculated with the oblongata emulsion from Mrs. J. have all succumbed with unmistakable and characteristic symptoms of rabies. Also that the three rabbits in the subseries likewise developed the typical paralytic form of rabies. Further, that the two check rabbits are still alive and their health apparently unimpaired at this writing." As a result of the microscopic lesions found by the histological examination of the plexiform ganglion on the pneumogastric nerve and of the bulb of the medulla, also of the experimental inoculation of rabbits, it seems justifiable to conclude that the person in question was suffering with rabies at the time of death.

a These animals were chloroformed eight months after inoculation and found to be in a healthful condition.

DESCRIPTION OF PLATE I.

Fig. 1. Section of normal plexiform ganglion stained with hematoxylin and eosin. Camera-lucida drawing made at the stage level with No. 4 compensating ocular and Zeiss 4 mm. objective.

Note the single layer of endothelial cells (a) lining the capsule of the ganglionic cells, the open pericellular space, and the appearance of the protoplasm and nuclei of the nerve cells (b).

Fig. 2. Section of the plexiform ganglion of Mrs. J. stained with hematoxylin and eosin. Camera-lucida drawing made at stage level with No. 4 compensating ocular and Zeiss 4 mm. objective.

The proliferation of the endothelial cells of the lining capsule (a) is well marked, as is also the destruction of the cell protoplasm (b) and the infiltration of leucocytes (c).

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Haines, del.

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FIG. 2. SECTION OF GANGLION SHOWING LESIONS OF RABIES.

BREUKER & KESSLER CO PHILADA

SPREAD OF TUBERCULOSIS AMONG HEALTHY CATTLE UPON EXPOSURE TO TUBERCULOUS CATTLE.

By E. C. SCHROEDER, M. D. V., and W. E. COTTON,

Superintendent and Expert Assistant of Experiment Station of Bureau of Animal Industry. A number of investigations have already been made regarding the rapidity with which tuberculosis spreads among healthy cattle, under various conditions, when exposed in stalls and stables previously occupied or occupied at the same time by cattle affected with tuberculosis. These investigations have generally shown that the introduction of a tubercular animal into a healthy herd will, in all probability, be followed by serious consequences in a comparatively short period of time. In fact, a healthy herd of cattle, through the introduction of a tubercular cow, in the light of the following experiment and the investigations above referred to, may in less than a single year become entirely tubercular. The importance of this fact not only in its simple economical bearing on the cattle industry, but also on the public health, is so great that it can hardly be sufficiently accentuated. This is especially true when the subject is contemplated in connection with the now well-established reputation of tuberculin as a diagnostic agent in tuberculosis, and the knowledge that, through the proper use of tuberculin, healthy herds of cattle can almost with absolute certainty be protected from exposure to tubercular cattle, and tubercular cattle can readily be separated from other cattle which have not yet become affected.

On January 27, 1903, in the following experiment 7 healthy cattle and 3 tubercular cows were confined in a stable containing 10 box stalls. The stalls were separated by solid 2-inch plank partitions, 6 feet high. Five of the healthy cattle and the 3 tubercular cows occupied different stalls each day, in a rotation which exposed each of the healthy cattle equally to the 3 tubercular cows. Two of the healthy cattle occupied stalls near the center of the stable and were at no time allowed to enter other stalls or to come into closer contact with any of the other cattle. On April 10, 1903, 1 of the 3 tubercular cows was removed from the stable, and 2 other and more severely affected cows were introduced. On June 12, 1903, 1 of the latter died and was found on autopsy to be affected with generalized tuberculosis; however, without disease of the udder or lymph glands associated with or near the udder. Eight guinea pigs which were fed the milk of this cow from

April 6 to June 8 were killed about two months after the feeding ceased and were found to be unaffected. Three guinea pigs received on April 15, 1903, each an intraabdominal injection of 5 c. c. of milk from this cow. Two of the guinea pigs died, respectively, on June 11 and June 29, affected with generalized tuberculosis, and the third was killed on September 4, 1903, and was found to be fat and free from all lesions of disease.

The 4 other tubercular cows used in the experiment are alive at this time [November 7, 1903]. Guinea pigs fed the milk of these cows remained healthy, and the same is true of guinea pigs which received intraabdominal injections, with the exception of the milk from 1 cow, which on injection caused generalized tuberculosis in 2 of 3 guinca pigs. The latter cow was one of the 2 introduced into the stable on April 10. The other 3 cows were so slightly affected with tuberculosis that the presence of the disease would have escaped the casual observer. A record of the exposed cattle follows:

Bull No. 263, yearling; in good condition; tested with tuberculin without reaction.

January 27, 1903.-Placed in stable with tubercular cattle. Occupied a stall about the center of the stable, which was separated from the other stalls by a 6-foot-high solid 2-inch plank partition. At no time did he enter a stall which had been previously occupied by a tubercular animal.

June 30, 1903.-Tested with tuberculin and gave a reaction which reached 3.6° F., at its highest point. a General condition, excellent.

August 3, 1903.-Killed and examined postmortem. Autopsy record follows: General condition, excellent. Posterior mediastinal glands are slightly enlarged and contain numerous small recent foci of tuberculosis. The anterior mediastinal glands are greatly enlarged and are filled with foci of tubercular material. Bronchial glands contain several small foci of recent tubercular disease.

Cow No. 257, about six years old; in good condition; tested with tuberculin without reaction.

January 27, 1903.—Placed in stable with tubercular cattle. Occupied a stall about the center of the stable, which was separated from the other stalls by a 6-foot-high solid 2-inch plank partition. At no time did she enter a stall which had been previously occupied by a tubercular animal.

June 25, 1903.—Produced a healthy female calf.

June 30, 1903.-Tested with tuberculin without reaction. August 3, 1903.-Killed and examined postmortem. Autopsy record follows: Several of the mediastinal glands are greatly enlarged and thickly sprinkled with small tubercular nodules, which are recent in character. Several small recent areas of tubercular disease sprinkled through the lung. The liver is adherent to the diaphragm in several places by bands of firm, white connective tissue. No tubercular lesions in the liver or portal glands. The right hind quarter of the udder is indurated, and the proper secreting tissue has been replaced by a thick, dense network of connective tissue supporting small masses of fat. This quarter of the udder secreted practically no milk. The other quarters of the udder healthy. The disease of the

a The amount of reaction in all these cases is determined by subtracting the highest temperature on the day before injection with tuberculin from the highest temperature on the following day.

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