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cal and bacteriological work on the Swiss type of cheese is done at Washington, the cheese being made at the Pennsylvania State College in cooperation with that institution. Experiments in the manufacture of the Cheddar type of cheese are carried on at Madison, Wis., in cooperation with the Agricultural Experiment Station of the University of Wisconsin. Work on the Roquefort type of cheese is conducted at Storrs, Conn., in cooperation with the Storrs Agricultural Experiment Station. Investigations on milk secretion are carried on at Columbia, Mo., in cooperation with the experiment station of the University of Missouri.
The work with milk during the year consisted mostly of a study of the bacteria of pasteurized and raw milk. In addition about 150 analyses of goat's milk were made, and the use of buttermilk and whey as by-products received attention.
Investigations were carried on pertaining to changes in storage butter, and experiments were made with a view to producing dried cultures for use in butter and cheese making. The results of the Roquefort cheese investigations for assisting the manufacture in this country of that well-known European variety of soft cheese will soon be ready for publication.
Some important results have been secured in the milk-secretion experiments, wherein certain cows were fed rations varying from below maintenance to fattening. These results will be published in due course. Work has also been done concerning the effect on the milk when cows are fed with cottonseed products.
THE STUDY AND CONTROL OF ANIMAL DISEASES. Some of the animal diseases which have been the subject of investigation and eradication during the fiscal year are Texas fever, tuberculosis, glanders, hog cholera, rabies, dourine of horses, scabies in sheep, cattle, and horses, lip-and-leg ulceration of sheep, ringworm of sheep, roundworms and tapeworms of sheep, gid in sheep, necrobacillosis of various animals, chronic bacterial dysentery of cattle, swamp fever of horses, and poultry diseases. A few facts concerning the more important of these will be mentioned.
TEXAS FEVER AND TICK ERADICATION. The eradication of the ticks which transmit the contagion of Texas fever of cattle and which inhabit the southern part of the country is proceeding vigorously in cooperation with State and local authorities. During the fiscal year the territory released from quarantine as a result of this work aggregated 10,965 square miles. Since the beginning of systematic work in exterminating these ticks five years ago there have been cleared of ticks and released from quarantine
23165°—AGR 1911- 4
139,821 square miles. This is about one-fifth of the original infested area.
Dipping experiments have been continued with a view to finding the most effective and economical means of ridding cattle and pastures of the ticks. Recent work shows that arsenic yields better results than the crude petroleum formerly used as a dip. Arsenical dips are therefore now being principally used.
During the year 4,016,048 inspections of southern cattle were made by employees of the Bureau of Animal Industry in connection with the work of tick eradication. The number of cattle permitted unrestricted movement under certificate was 103,338, and of these 45,613 were dipped or otherwise treated.
The movement of cattle from the quarantined area is carefully regulated so that the disease can not be transmitted to animals outside the area. There were shipped from the quarantined area to northern markets during the quarantine season of 1910, under the supervision and in accordance with the regulations of the department, 1,065,119 cattle.
SCABIES OF SHEEP AND CATTLE.
In the work for the eradication of the parasitic diseases known as scabies in sheep and cattle, employees of the Bureau of Animal Industry made 56,584,129 inspections of sheep and 18,593,251 inspections of cattle, and supervised 12,715,631 dippings of sheep and 1,234,123 dippings of cattle. There were released from the quarantine for scabies of sheep 22,560 square miles in Oregon, and from the quarantine for scabies of cattle 14,810 square miles in South Dakota, Nebraska, and Kansas.
TUBERCULOSIS. Tuberculosis has been for many years a subject of investigation by the Bureau of Animal Industry. During the year the problem of protecting animals from the disease by vaccination has been studied at the Bureau Experiment Station. Some favorable results have been obtained, but, as the only methods found effective require the use of living tubercle bacilli, such methods are not considered practicable for general use because of the danger of spreading the disease.
Some important results were obtained during the year in the pathological laboratory through a study of material from hogs fed upon garbage from the kitchen of an institution where tuberculous insane were kept. Both the human and bovine types of tubercle bacilli were obtained from these hogs. Further tests were also made in the laboratory with the ophthalmic and intradermal methods of applying the tuberculin test for the diagnosis of the disease.
The work of eradicating bovine tuberculosis in the District of Columbia as reported last year has been followed by the systematic
retesting of cattle with tuberculin to guard against the reappearance or reintroduction of the disease. The testing of dairy herds in Maryland and Virginia which supply milk to the city of Washington has also been continued. During the fiscal year the tuberculin test was applied to 4,327 cattle in Virginia, 1,847 in Maryland, and 1,967 in the District of Columbia. The percentage of diseased cattle among those not previously tested was 16.06, while in the retests it was only 3.95. Seventy-three reacting animals in the District of Columbia were slaughtered, and in all but one case the lesions of tuberculosis were found on post-mortem examination, thus verifying the result of the tuberculin test.
INSPECTION OF LIVE STOCK FOR INTERSTATE MOVEMENT.
In addition to work already reported, the bureau inspects live stock for interstate movement for purposes other than immediate slaughter, and tests cattle with tuberculin and horses and mules with mallein, when such measures are required by the laws of the State or Territory to which the animals are destined. In this work 52,230 cattle were inspected during the year, of which 18,778 were tested with tuberculin. Similarly 34,789 horses and mules were inspected and 5,789 tested with mallein.
DOURINE OF HORSES.
An outbreak of a disease of horses in Iowa, suspected of being dourine, was reported in May, and a prompt investigation was made, as a result of which the scientists of the Bureau of Animal Industry were able by prolonged search with the microscope to find in the blood the causative organism of the disease. This was the first time that the organism had been demonstrated in a natural infection in the United States, although the disease had existed in this country for some years and had been stamped out about five years ago. The manner in which the present outbreak was introduced was not positively determined, although indications pointed strongly to its having been brought in by an imported stallion. Strict quarantine measures were at once enforced, with the cooperation of the Iowa State authorities, and the disease is now believed to be practically eradicated.
The practical value of the serum for the prevention of hog cholera, produced after long experimentation by the Bureau of Animal Industry, is now generally recognized. At the suggestion of the department, the large hog-raising States have taken up the manufacture and distribution of the serum, and upward of 200,000 inoculations have already been made by State officials in 21 different States. The results of this work have been extremely favorable.
At the request of Nebraska State officials and the Nebraska Swine Breeders' Association the bureau carried out a demonstration with the preventive serum at South Omaha during the year, similar to a previous test held at Kansas City. Thirty young hogs were used, of which 4 were inoculated with blood from hogs sick of hog cholera, 18 were given one dose of the serum, and the remaining 8 were left untreated. All the hogs were then placed together in one pen, the experiment extending from July 23 to September 17. The result was that the 4 inoculated hogs as well as the 8 untreated hogs died of hog cholera, while the 18 hogs that had been given the serum all remained perfectly well.
During the fiscal year the brain tissues from 173 suspected cases of rabies were examined in the pathological laboratory at Washington, including 152 dogs, 8 cattle, 2 hogs, 1 horse, and 1 goat. The great majority of these cases came from the District of Columbia and the surrounding country. One hundred and thirty proved to be positive, the method of diagnosis being the detection of Negri bodies, supplemented in some instances by the inoculation of rabbits.
EXPORT AND IMPORT ANIMALS.
During the fiscal year there were made 370,369 inspections of American and 32,470 inspections of Canadian animals for export. The number of animals actually exported was 171,006; the greater number of inspections is accounted for by the fact that many of the animals were inspected two or more times. This work also includes the supervision of vessels, of which 438 inspections were made.
All live stock for export to Canada are inspected by bureau veterinarians, and cattle, horses, and mules must in addition be testedthe cattle with tuberculin and the horses and mules with mallein. During the year 13,404 horses, 1,046 mules, and 460 cattle were thus tested, the reactions numbering 251 horses, 12 mules, and 16 cattle. The other inspections for Canada were 28,428 sheep, 25 goats, and 110 swine.
A strict inspection, with quarantine in certain cases, is maintained over all animals imported from foreign countries. This is necessary in order to exclude the numerous animal diseases which are prevalent in other parts of the world. For this purpose hay, hides, wool, etc., are also inspected and disinfection required. The total number of import animals inspected during the year was 261,478, and of these 4,127 were quarantined in accordance with the regulations,
DISTRIBUTION OF VACCINE, ETC.
Over 1,000,000 doses of blackleg vaccine were prepared and sent out during the year by the Bureau of Animal Industry. The necessity for immunization against this virulent disease of young cattle is being more thoroughly appreciated by cattle raisers, and the department vaccine is the means of preventing heavy losses.
Tuberculin and mallein are furnished to State, county, and municipal officials for the diagnosis of tuberculosis and glanders, respectively. During the past year 422,043 doses of tuberculin and 91,642 doses of mallein were sent out.
The department does not distribute the preventive serum for hog cholera, this work having been taken up by State laboratories, as already mentioned.
NEEDED LEGISLATION RELATING TO ANIMAL INDUSTRY.
Further legislation by Congress is urgently needed in order to enable the department to deal more effectively with matters relating to the live-stock industry.
It is especially desirable that the Secretary of Agriculture should have power to control and supervise the manufacture and importation of vaccines, serums, and like substances used for treatment of animals, so as to insure their purity and potency. Such preparations, when contaminated, have in the past been responsible for the introduction of contagious diseases into the country. The great cost of eradicating these outbreaks should alone be a sufficient reason for granting the authority required.
Further legislation is also needed for the regulation of live stock in interstate transportation, so as to prevent more effectively the spread of contagious disease and to secure more humane treatment of the animals in transit.
These matters are discussed more fully and specifically in my report for 1910 and in the report of the Chief of the Bureau of Animal Industry for the fiscal year 1911.
BUREAU OF PLANT INDUSTRY.
There are over 6,300,000 farms in the United States, and the demand for help from these farms is growing greater each year. The Bureau of Plant Industry is endeavoring to meet some of these demands, and its activities now extend into many fields, covering research, experiments, and demonstrations. The primary function of the bureau is to develop and encourage constructive agriculture by assisting the farmer to increase the output per acre and at the same time to build up and maintain the fertility of the land. The