Hydrophobia or Tuberculosis?
By J. R. Leadsworth
In Bulletin No. 44, Bureau of Animal Industry, United States Department of Agriculture, some information is furnished which ought to interest the general public. A highly fatal disease appeared among the cattle in the dairy herd belonging to the government asylum for the insane at St. Elizabeth, D. C. In the course of two weeks from the beginning of the outbreak eighteen animals had died, when the disease suddenly stopped. From the nervous symptoms manifested by these cows before death, and from the fact that a rabid dog had been seen among them a few weeks before, evidence pointed strongly to the epidemic as being rabies, or hydrophobia. Post-mortem examination of the carcasses seemed to confirm the diagnosis. But it was also manifest from this examination that of the eighteen cows at least twelve of the dead animals showed extensive tuberculous lesions. This was a startling discovery, inasmuch as this herd was high bred, great care having been taken in their selection as well as in their care and stabling. But in order to determine the extent of this tubercular infection it was decided to subject the whole herd of one hundred and two cows to the tuberculin test. Imagine the surprise when it seemed evident that seventy-six of the one hundred and two cows were far advanced in tuberculosis. Post-mortem examinations afterward confirmed the reliability of these tests. Previously to the slaughter of these animals it was decided to demonstrate to the satisfaction of the department that milk from such animals would transmit the disease. Taking advantage of the fact that guinea-pigs are as susceptible as man is to tuberculosis, a number of these animals were selected for the experiments. Several of them were killed and examined to preclude the possibility of a previous infection. After having fed the guinea-pigs upon this infected milk for only a few weeks, the animals were killed or otherwise examined, and over twenty-one per cent were found in various stages of the disease. In the light of these figures is it any wonder that so many artificially fed children die from summer complaint or some form of bowel trouble? Six months after first testing the herd, the remaining twenty-six cows were subjected to a second tuberculin test, resulting in eight of the number being condemned. These were afterward proved to be infected, although most of them were not far advanced in the disease. But here is the part that should interest flesh-eaters: being only slightly infected, it was deemed too much of a loss to condemn the meat, hence they were passed to the butcher. Here is the post-mortem report of one so passed:— “One small focus in right retropharyngeal gland, one nodule size of a pigeon’s egg in right cephalic lobe, and four foci containing cheesy deposit in ventral lobe of left lung. Carcass passed.”
This, with a number of others, was considered worthy of a better burying place than the “cold, cold ground,” so was turned over to the butcher, who, for so much a pound, agreed to deposit the remains in a style that would compensate for the untimely end of the deceased. As a result of these investigations, the following are the conclusions arrived at by the department:— 1. The tubercle-bacillus may be demonstrated in milk from tuberculous cows when the udders show no perceptible evidence of disease, either macroscopically or microscopically. 2. The bacillus of tuberculosis may be excreted from such an udder in sufficient numbers to produce infection in experimental animals both by ingestion and by inoculation. 3. That in cows suffering from tuberculosis the udder may, therefore, become infected at any moment. 4. The presence of the tubercle-bacillus in the milk of tuberculosis is not constant, but varies from day to day. 5. Cows secreting virulent milk may be affected with tuberculosis to a degree12that can be detected only by the tuberculin test. 6. The physical examination or general appearance of the animal can not foretell the infectiveness of the milk. 7. The milk of all cows which have reacted to the tuberculin test should be considered as suspicious, and should be subjected to sterilization before using. 8. Still better, tuberculous cows should not be used for general dairy purposes.