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Similarly, the Bureau has had occasion to test with tuberculin a large number of purebred cattle intended for shipment into Canada, Argentina, Uruguay, and other countries requiring such certificates of health; and the breeders of full-blooded cattle are also being encouraged and assisted by the Bureau in cleaning their herds. By such testing, new centers of infection are located, advice is given to the breeders as to the best methods for controlling the disease, and the State authorities are notified for such action as they may deem advisable.

Furthermore, the meat-inspection service during the past two years has been used as an adjunct in determining the extent and prevalence of tuberculosis in individual States. This has been accomplished by obtaining all available information concerning each lot of tuberculous animals slaughtered, and in case these animals can be traced back to the farm whence they came, the breeder or feeder, as the case may be, is notified concerning the post-mortem findings on his animals, and likewise the State veterinarian or sanitary officer is informed, in order that the testing of the remainder of the herd and the disinfection of the premises may be properly carried out.

In order to prevent as far as possible the interstate traffic which has evidently been going on in cattle that had reacted to the tuberculin test, the Secretary of Agriculture in 1907 issued a notice classifying tuberculosis as one of the contagious diseases to be controlled under the law, and calling attention to the fact that it was an offense against the law to drive or transport cattle that were known to be tuberculous across State lines. While the fact that such action is illegal may not cause it to be entirely stopped, law-abiding citizens will conform to the law, and with the earnest prosecution of all cases of violation detected this practice will be greatly reduced. Notice has been furnished railroad and steamship companies, cattle raisers, and stock papers that it is a violation of the Federal statutes to ship animals affected with tuberculosis from one State to another, and the only hardship it occasions is with stock owners in one State who are unable to send their cattle to a packinghouse center located in close proximity in an adjoining State. However, the benefits of such an order are so superior that they greatly overcome the few disadvantages.

Congress has also granted power to the Department of Agriculture to examine and report upon the results obtained from the use of various kinds of tuberculin sold in this country. This power of keeping the public informed upon the value of such an important biological product as tuberculin came none too soon, for worthless tuberculin has been found on the market, and there can be no question that many inconsistent results-results which were embarrassing to the testers and caused dissatisfaction among the stockmen—

from the use of different tuberculins can be explained by the inertness of certain of these products.

The testing of a few dairy herds near the District of Columbia showed the widespread distribution of tuberculosis and the serious extent to which it prevailed among the cattle in that vicinity. This knowledge, coupled with the agitation of the citizens of Washington for a pure milk supply, led the Bureau to volunteer to test all herds supplying Washington with milk, provided the owners would agree to disinfect the premises afterwards and endeavor so far as possible to keep their herds free of this disease. The herds belonging to Government institutions and other public organizations in various parts of the country have likewise been tested by the Bureau, not only as a repressive measure, but also as an object lesson for the owners of other dairy herds in their vicinity.

Since 1893 the Bureau has been constantly assisting some of the States in controlling tuberculosis by preparing and distributing tuberculin to their State and municipal health authorities and sanitary officers, and during the last few years the demand has been greatly increased, 215,000 doses having been sent out in the past year.

In the appropriation act for the Department of Agriculture for the fiscal year 1909 Congress authorized a study of the extent and prevalence of tuberculosis in the United States. In order to determine these facts both quickly and accurately the work will necessarily be undertaken in those States where cooperation can be obtained, not only from the standpoint of organization and funds, but also with reference to having proper laws regarding the entry of tuberculous cattle; in other words, it will be the object to help those States that are endeavoring to help themselves. Already several veterinary inspectors have been stationed at important shipping points for the purpose of accommodating shippers who desire to have cattle tested which are destined for States requiring the tuberculin-test certificates, and while this work at present is entirely voluntary, the establishment of a large number of such points would probably follow if more States had compulsory tuberculin-test laws.

It will therefore be seen that a constantly increasing activity relative to the suppression of tuberculosis is being manifested by the Bureau of Animal Industry, and I believe the day is not far distant when all breeding and dairy cattle crossing State lines will be required to show a tuberculin-test bill of health. A great impulse will be given this subject in consequence of the educational propaganda resulting from the International Congress on Tuberculosis held in Washington. If the States themselves would all enact such laws, the enforcement of an order for the testing of the above classes of cattle entering interstate commerce, and the appointment of veterinary tuberculin testers by the Government to all the principal

shipping centers, would be more likely to follow. In this event it probably would not be long before the country would be divided into districts for the eradication of tuberculosis, as it is at present in the South for the repression of the fever tick, and in the West for the extermination of the cattle and sheep scab mites.

The effort to control tuberculosis is a most reasonable and proper one, and if conservatively directed should receive the support of every friend of the cattle industry. Not only is tuberculosis a disease to be dreaded because of the value of the cattle which it injures or destroys, but its existence is believed by the best sanitary authorities to be a serious menace to the health of the consumers of meat and dairy products. The individual States therefore have good reason for desiring to stop the importation from other States of tuberculous animals and for adopting measures intended to lessen or control the disease within their own borders. The herds of the United States are far less seriously affected with tuberculosis than are those of European countries, and the proportion of animals affected in Europe indicates both the danger which threatens our herds if the disease is allowed to progress here, and the importance of thorough measures to prevent it from becoming as prevalent in this country as it is in that part of the world.



By JOHN R. MOHLER, V. M. D., Chief of the Pathological Division,


HENRY J. WASHBURN, D. V. S., Senior Pathologist, Pathological Division.


The ravages of tuberculosis in the avian family are so patent that the gravity and increasing prevalence of this affection must not be ignored. The first outbreak of fowl tuberculosis in the United States was reported by Pernot in Oregon during 1900. The disease has since been located in California by Moore and Ward in 1903, in Canada by Higgins in 1905, in New York by Burnett in 1907, and in Michigan by the Bureau of Animal Industry in 1907. Four other outbreaks of avian tuberculosis have been studied by the Pathological Division since 1907, which indicates the probability of the disease being much more extensive in its depredations than has hitherto been realized. Other writers have reported tuberculosis among poultry, but the failure to make bacteriological demonstrations makes these reports useless as scientific evidence.

In the cases investigated by the Pathological Division both dead and live birds were received, showing in some instances incipient and in others generalized tuberculosis, as attested by microscopic demonstration of the tubercle bacillus, and the feeding experiments carried on afterwards resulted successfully in from three to five months. The importance of continued investigation in this direction is shown by the fact that numerous vague diagnoses under the title of liver disease, spotted liver, "going light," rheumatism, etc., are common among poultry raisers, some of which in the above-mentioned demonstrations have been proved to be tuberculosis, thus suggesting that avian tuberculosis is rapidly becoming disseminated. The finding by all investigators of multitudes of tubercle bacilli in the feces suggests the ease with which the disease may be spread throughout the flock. And it must be admitted in the present state of our knowledge of this disease in mammals and birds that the appearance of tuberculosis in a flock of chickens or other poultry opens up for that locality all the questions connected with this malady.

Rivolta, Straus, and other writers early demonstrated the fact that after tubercle bacilli have been retained for generations in the

tissues of fowls they will not readily affect mammals. Conversely, mammalian tubercle bacilli are said to affect fowl very infrequently; in fact, many noted bacteriologists affirm most positively that it is utterly impossible by any manner of infection or inoculation to infect fowls with mammalian tubercle bacilli. It becomes, therefore, of interest to investigate any case in which tuberculosis seems to have been conveyed by natural means of transfer from birds to mammals, or vice versa. It is furthermore very interesting to study the relations between tubercle bacilli from various species of animals and to make test inoculations upon all available species of laboratory animals with as many varieties of cultures as may be obtainable.


The occurrence of an outbreak of tuberculosis among the poultry on a ranch in Oregon which seemed to be extending to the swine of the same farm, causing many of them to be condemned as tuberculous when inspected at the abattoir, presented an opportunity for inaugurating a systematic study of this outbreak, especially in regard to the transmissibility of the disease from the birds to the hogs that were kept near them upon the home ranch, and also to other mammals experimentally.

This outbreak was called to our attention by Dr. S. W. McClure, an inspector of this Bureau located in Oregon, in the following report:

The history of this infection is somewhat interesting. About one year ago Mr. B. had 65 grown chickens; one or two of them were noticed to be sick, and, after a lingering illness, died. About three months later other members of the flock became affected and died in the same manner. Altogether about 30 of the 65 died during the last six months, several of which were examined by the owner and found to be in the same condition as those which we examined. He now has remaining less than 20 of his original flock, and most of them are affected with the disease. These chickens are in the yard with about 30 hogs, and those that have died have been consumed by the hogs. He has slaughtered some of the hogs lately and has found their livers affected exactly similarly to those of the chickens.

The facts shown in this letter and reports from a neighboring abattoir which confirmed the presence of tuberculosis in the swine made further investigation desirable, especially as there was nothing in the history of the outbreak among the hogs to indicate that they derived their infection from tuberculous cattle or their products. Several fowls were therefore secured and shipped to the laboratory at Washington. The following letter accompanied them:

The four hens forwarded were secured from the ranch of Mr. B. referred to in my previous letter. These are all the chickens that he has left. On my earlier visit to this ranch I found hens that presented no physical symptoms whatever, and yet they showed on post-mortem the advanced lesions of tuber

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