In this compilation the following basis has been adopted in determining what constitutes a reaction, as in the experience of the Bureau of Animal Industry this method has been found to give reliable results: A reaction consists of a rise of 2° F. or more above the highest temperature before injection, provided the maximum temperature after injection reaches 103.8° F.

It should also be explained that the number of tests shown in the table represents only those of which the Bureau received reports, and not the entire number of doses of tuberculin prepared and distributed by the Bureau during the period named.

Assuming that 10 per cent represents the prevalence of tuberculosis among dairy cattle as indicated by tuberculin tests, and 1 per cent among cattle slaughtered for beef, as shown by the meat-inspection figures, and taking 21,194,000 as the number of milch cows and 50,073,000 as the number of other cattle in the United States on January 1, 1908, as estimated by the Bureau of Statistics of the Department of Agriculture, we conclude that as a general average about 3.5 per cent of the cattle of this county are affected with tuberculosis.

ECONOMIC LOSSES FROM ANIMAL TUBERCULOSIS.

While the financial loss caused by tuberculosis of farm animals can not be calculated with exactness, a study of the subject affords a basis for estimates sufficiently close to show that it is a serious drain on the live-stock industry.

LOSS ON TUBERCULOUS ANIMALS SLAUGHTERED.

The writer recently made an effort to collect reliable data as to the loss caused by tuberculosis in animals slaughtered under Government meat inspection. Carefully compiled figures were obtained from a number of large firms engaged in the slaughtering and meat-packing business, in one instance the calculations covering an entire year's business. In arriving at the loss the general method, in brief, was to deduct from the average cost of a live animal of a certain class the average amount realized from a tuberculous carcass of that class, the difference representing the loss.

Under the inspection system the animals found tuberculous are disposed of in three classes, according to the extent of the disease. Carcasses which show very slight infection may often be safely passed for food after the removal of the lesions, the loss in such cases of course being small. Other carcasses, affected to a somewhat greater degree, but still not badly diseased, are allowed to be rendered into lard or tallow at a sterilizing temperature after all diseased portions have been cut away and condemned. In these cases the loss is more considerable. A third class comprises carcasses that are considered unfit for food in any form and are totally condemned. The loss on these

is still greater, amounting in the case of cattle to about three-fourths of the cost. The salvage consists of the hide, grease, fertilizer, etc.

The loss on condemned adult cattle was found to vary from $10 to $75 a head, according to grade, price, weight, etc. While the loss per carcass is of course heavier on the higher priced animals, the proportion of condemnations is much greater among the cheaper grades. After weighing these factors and studying the figures the writer has concluded that for the purpose of this paper the condemned cattle may be grouped in two general classes, one representing about the average of the better grades, including those known as native and western cattle, in which steers largely predominate, and the other representing the cheaper grades and lighter weights, including "cutters" and "canners," largely cows. At present Chicago market prices the loss on the first class, when condemned, is estimated at $45 a head and on the second class at $18 a head. These figures are believed to be conservative and below rather than above the actual losses, as are all the estimates made in this article. It is also estimated that two-thirds of the condemnations occur in the cheaper class of cattle and one-third in the higher class. This proportion gives $27 a head as the general average loss on condemned cattle. On carcasses rendered into tallow the average loss is estimated at $20. On a percentage basis the combined average loss on cattle carcasses condemned and those rendered into tallow is about 70 per cent of the cost of the live animals. The loss on beef carcasses passed for food is very slight, being estimated at 50 cents each.

The loss on calves condemned is about $7 a head, and the loss on those passed for food after condemning an organ or part is estimated at 25 cents a head.

The average loss on tuberculous hogs is estimated at $8.50 (or 55 per cent) on those condemned, $5.75 (or 38 per cent) on those rendered into lard, and 50 cents on those passed for food.

Applying the foregoing figures to the number of animals found tuberculous in the Federal meat inspection during the fiscal year ending June 30, 1908, the annual loss is as follows:

The significance of this loss may be better appreciated when it is known that tuberculosis is the cause of two-thirds of the entire loss resulting from condemnations at the time of slaughter in the meatinspection service.

The loss on animals slaughtered without Federal inspection can not be so readily computed. Some States and municipalities have more

or less efficient inspection systems, but the great majority of the animals slaughtered without Government inspection are not subjected to inspection of any kind, and it has already been pointed out that tuberculosis is doubtless more prevalent among them than among those coming under Federal inspection. It is safe to say, however, that without inspection the actual loss is very slight. Nevertheless the writer is of the opinion that the loss should be computed as it would occur under efficient inspection. Applying to the number of animals slaughtered without Federal inspection the same factors that were used for those coming under inspection, but assuming that the cattle are generally of an inferior quality and worth 25 per cent less, it is estimated that the loss because of tuberculosis among animals slaughtered without Government inspection would, if proper inspection were applied, reach $1,720,000 a year, making the aggregate estimated loss on all food animals killed in the United States $3,832,435 annually.

DEPRECIATION IN VALUE AND OTHER LOSSES.

Aside from the loss on animals slaughtered, tuberculosis unquestionably causes a considerable depreciation in the value of those remaining alive. There are no definite data upon which to calculate this depreciation, but it is entirely reasonable to estimate that tuberculous milch cows decrease in value annually at least one-tenth of what the loss would be if they were slaughtered and condemned, while other cattle depreciate annually one-third and hogs one-half of such oss. On this basis, taking the estimate of the Bureau of Statistics of the Department of Agriculture as to the number and value of farm animals in the United States January 1, 1908, and assuming that 10 per cent of dairy cattle, 1 per cent of other cattle, and 2 per cent of hogs are tuberculous, the total annual depreciation is no less than $8,049,889.

Tuberculosis also has the effect of decreasing the productiveness of dairy cows by diminishing the yield of milk as well as, perhaps in some cases, by shortening their lives, and consequently the period during which they produce milk. Again, the amount of the loss is largely a matter of conjecture, but the writer feels that he is within reason in estimating that the average milk yield of a tuberculous cow is 10 per cent less than that of a healthy cow, and on this basis the annual loss, valuing milk at wholesale prices, is fully $10,000,000. Serious damage is caused by tuberculosis from the standpoint of breeding. The disease is found to a greater extent in purebred herds than in common stock. In adding fine animals with a view to “breeding up" his herd, an owner may unwittingly also introduce tuberculosis, with disastrous results. By causing unthriftiness and

impairment of fecundity the disease has an adverse effect upon the number and value of the offspring.

The influence of tuberculosis toward increasing the cost of meat and dairy products has already been alluded to. There is also a considerable economic loss resulting from the destruction of cattle in the efforts already being made in some States to eliminate the disease. The trade in live animals and in animal food products also suffers losses because of tuberculosis. Doubtless there are still other sources of loss chargeable to this disease in live stock, such as the expense of maintaining a sanitary service, disinfection of premises, etc.

THE AGGREGATE LOSS.

Taking into consideration the various items mentioned, the tribute which the United States pays each year to this scourge among its farm animals aggregates more than $23,000,000.

Such a loss is too great, merely as a matter of economics, to be allowed to continue and increase from year to year. And when in addition we consider the bearing of animal tuberculosis on human health, it seems imperative that vigorous measures should be taken to eradicate the disease from our herds, especially when such eradication seems entirely possible and practicable.

THE CONTROL AND ERADICATION OF TUBERCULOSIS.

Any efforts to reduce or control tuberculosis of live stock in order to be of lasting value must have eradication in view as the final object. We should not temporize with such an insidious malady, but should adopt aggressive measures that will insure success within a reasonable time.

It has been clearly shown by the work of the Bureau of Animal Industry and by other investigations that hogs readily contract tuberculosis from cattle and that diseased cattle are the primary source of the infection in hogs. The main problem, therefore, is to eradicate the disease from cattle, and when this is accomplished tuberculosis may easily be eradicated from hogs.

The eradication of animal tuberculosis may as well be recognized at the outset as a tremendous undertaking, which will require not only the best efforts of the authorities in charge but the sympathy and support of stock owners and the general public. Large sums of money will be necessary, and in order that adequate appropriations may be obtained, the necessity and importance of the work must be generally realized and understood.

WHAT MAY BE DONE BY INDIVIDUALS.

With proper assistance much can be done by the individual stock owner to exclude and eliminate the disease from his animals. He

should be careful to avoid the introduction of tuberculosis into his herd by requiring that any cattle purchased shall have passed the tuberculin test. He can also do much to promote the health of his animals by keeping them in sanitary stables and under hygienic conditions. When tuberculosis is suspected he should notify the authorities and have his cattle tested. When the presence of the disease is known the safest course is to have the affected animals slaughtered, but in the case of valuable breeding stock, where slaughter would involve great sacrifice, the Bang system of segregation may be used.

EDUCATIONAL WORK.

The individual, however, must first be aroused as to the danger of having tuberculosis in his herd and the importance of eradicating it, and he must also be informed as to the nature of the disease and the best methods of combating it. Valuable work in this direction may be done by the general and agricultural press and by official publications, also by lectures at public gatherings, farmers' institutes, etc.

GOVERNMENT AND STATE MEASURES.

If the campaign for the eradication of animal tuberculosis is to be comprehensive, systematic, and generally successful, it must be directed by Federal and State officials conjointly, who must be armed with adequate laws and funds and supported by public opinion.

Excellent work has been done by the authorities of several States during recent years, but a study of the laws and regulations of all the States shows that in most of them the importance of the subject is not appreciated. Thirteen of the States at present require the tuberculin test on cattle brought in, this requirement usually being limited to cattle intended for dairy or breeding purposes. Fourteen States have provisions for the slaughter of animals found affected with tuberculosis and the payment of indemnity to the owners, while a few others' give authority for condemnation and slaughter without making provision for indemnity.

The work of the Federal Government, as carried on by the Bureau of Animal Industry, so far consists (1) in supplying tuberculin free of charge to State officers, (2) in endeavoring to prevent the interstate shipment of tuberculous animals, and (3) in tracing when practicable the origin of animals found affected with tuberculosis in the meatinspection service and notifying State authorities.

As a basis for further work Federal and State authorities should first determine in what localities tuberculosis exists to the greatest extent among live stock (where this has not already been done), and should first apply the tuberculin test generally and systematically to cattle in such sections.