Delepine, S. Brit. Med. Jour., 1898, vol. 2, p. 918.

In a popular lecture, gives the following results with milks collected by health officers of Liverpool, Manchester, and elsewhere:

(a) Seven specimens unmixed milk from cows showing no evidence of tuberculosis. Tubercle bacilli in none of the specimens.

(b) Twenty-two specimens unmixed milk from cows showing distinct evidence of tuberculosis and in 6 cases udder involvement. Tubercle bacilli in 27.24 per cent.

(c) Fifty-four specimens mixed town milk. Tubercle bacilli in 5.55 per cent.

(d) One hundred and twenty-five specimens country farm milk. Tubercle bacilli in 17.6 per cent.

The presence of tubercle bacilli was determined by inoculation of guinea pigs and their post-mortem examination.

Petri. Zum Nachweis der Tuberkelbacilli in Butter und Milch. Arb. a. d. kais. Ges.-Amt., XIV, 1898, p. 1.

Milk specimens taken from various places in Berlin. Centrifuged in 150 cubic centimeter flasks. Three cubic centimeters each of cream, skim milk, and sediment injected into 4 guinea pigs (12) animals for each specimen). Later, on account of the lack of animals, 5 cubic centimeters from each specimen were inoculated into each of 4 guinea pigs.

Sixty-four specimens were examined. Tubercle bacilli were demonstrated in nine (14 per cent). Tubercle bacilli-like rods, not true tubercle bacilli in 4 specimens (6.3 per cent).

It appears that 200 out of the 478 animals died, mostly of peritonitis within the first three weeks, thus eliminating 7 specimens from consideration, and leaving 57 on which to base a percentage of incidence. As 9 of these contained tubercle bacilli, the corrected percentage would be 17.5.

The importance of using a large number of animals for each specimen is shown by the fact that in only 3 of the 9 positive specimens did more than 1 animal become tuberculous. In these 3 cases there were 2.

Ascher. Untersuchungungen von Butter und Milch auf Tuberkelbacillen. Zeit. f. Hyg., Bd. 32, 1899, S. 329.

Injected 17 specimens of Koningsberg milk into guinea pigs intraperitoneally. One of the animals became tuberculous. The milk was partly centrifuged, and the cream and sediment injected, and partly uncentrifuged. No other acid-fast bacilli found.

The first streams from the milking were used, which may account for the lower percentage of infected specimens detected by him than by Rabinowitsch, who used the last part of the milking. The com

parison of results with these different portions of the milking may throw light upon the source of infection of the milk, whether from feces or from the milk glands.

Jaeger. Ueber die Möglichkeit tuberkulöser Infektion des Lymph-systems durch Milch und Milchproducte. Hyg. Rundsch, 1899, IX, p. 801.

Examined the milk supplied to a large hospital in Königsberg. The dairy was in good condition and frequently inspected, but the cows were not tested with tuberculin.

Six guinea pigs were injected with the milk intraperitoneally. Two died of sepsis, 2 remained normal, and 2 developed tuberculosis. One hundred specimens were examined by the coverglass method for the tubercle bacillus, which was demonstrated in 7 specimens. Kanthack, A. A., and Sladen, E. S. St. B. Influence of the Milk Supply on the Spread of Tuberculosis. Lancet, 1899, vol. I, p. 74.

Examined the milk supply of the various colleges in Cambridge for the presence of the tubercle bacillus. Milk from 16 dairies was examined, 3 specimens from each. Two guinea pigs were injected subcutaneously with each specimen, one from the cream layer and the other from the sediment, after centrifuging 10 cubic centimeters of the milk for minutes; guinea pigs examined after death from disease or killed, the characteristic histological tubercle being deemed necessary for the diagnosis of tuberculosis. Of 33 animals suspected of being tuberculous 10 were found by microscopical examination to be free from the disease, while of 23 having typical histological tubercular lesions, 16 showed the presence of the bacillus.

Results: Of 16 daries examined, 9 furnished tubercular milk. Of 90 guinea pigs inoculated, 23 died from tuberculosis (25.55 per cent). It is interesting to note that 13 of these were inoculated with the cream layer, while only 10 received the sediment.

Macfadyen, Allan. Lancet, 1899, vol. II, p. 849.

In a report of work done at the Jenner Institute for the Hackney vestry, it appears that of 100 specimens submitted for examination 23 had to be excluded from the results because of the premature death of the test animals. Of the remaining 77 specimens, 17, or 22 per cent, were found to be infected with virulent tubercle bacilli. The milk was centrifuged 30 minutes, the cream removed and the milk recentrifuged for 30 minutes. The sediment was then used for inoculating guinea pigs.

Ostertag. Zeit. f Fleisch- und Milchhygiene, IX, No. 12, 1899, p. 221.

Examined the milk of some 50 cows which had no clinical evidence of tuberculosis, but had reacted to tuberculin. Milk received with

complete precautions into liter flasks and immediately cooled. The cream rose during transportation and was pipetted off, and to it was added enough of the milk to make 80 cubic centimeters. This mixture was then centrifuged, and a mixture of cream, skim milk, and sediment injected into guinea pigs. Three or four animals were injected with 10 cubic centimeters of each specimen. Each specimen was also examined microscopically for the presence of tubercle bacilli and the remainder was fed to guinea pigs.

Tubercle bacilli were not found in any specimen of the milk by microscopic examination. No pseudo-tubercle bacilli were found. Only 1 animal contracted tuberculosis out of all those injected, representing 1 specimen of 49. The other 3 animals receiving this same milk remained healthy and proved normal on section. The authors, for reasons which they give, do not regard this one case of tubercular infection as being due to the milk. They conclude that there were no tubercle bacilli in any of the 49 specimens. Fourteen specimens of the mixed milk from this herd were then examined. Only 11 remained for consideration. One of the injected guinea pigs was found tuberculous on being killed after seventy-one days, but the lesions were slight and the animal had lost only 20 grams. None of the fed animals became tuberculous.

Rabinowitsch, Lydia, and Kempner, Walter. Zeit. Hyg. XXXI, 1899, p. 137.

Recalls the results of earlier experiments of Rabinowitsch, in which of 25 samples of Berlin milk examined (1897), 7 (28 per cent) contained tubercle bacilli. The milk was centrifuged and a mixture of the cream and sediment layers injected into the peritoneum of guinea pigs.

The present article deals with an examination of the milk of cows reacting to tuberculin. Of 14 such cows, 10, or 71.4 per cent, gave milk containing tubercle bacilli. The condition of these cows is here detailed: Only 1 had pronounced udder tuberculosis. Another had udder tuberculosis demonstrable only histologically. Three cows with advanced generalized tuberculosis gave histologically the picture of chronic interstitial inflammation of the udder. One cow had low grade tuberculosis. One had râles on one examination, but none on the next two. Two cows had no symptom of tuberculosis. Another showed symptoms of beginning tuberculosis only on the second and third examinations.

This demonstrates that in beginning tuberculosis without discoverable udder disease, and in latent tuberculosis demonstrable only by the tuberculin reaction, the tubercle bacilli may be present in the milk. They believe that repeated examination would have shown tubercle bacilli in the milk of more of these cows.

Boyce. (Results given by Annett, Lancet, 1900, p. 160.)

He examined the market milk of Liverpool, England; his results are given in the following table:

The superiority of the town milk is attributed to the inspections conducted in town.

Rabinowitsch, Lydia. Deut. med. Woch., XXVI, 1900, p. 416.

Repeatedly examined the milk of eight Berlin dairies. This milk was designed especially for the use of children, was not sterilized, and sold for 35 to 60 pfennig per liter. In three of these dairies the cows were rigidly tuberculin tested. No tubercle bacilli were ever found in this milk. In the other five the cows were subjected to clinical oversight by veterinarians, but the tuberculin test was employed only now and then upon suspicious animals. In three of these five dairies the milk was found to contain tubercle bacilli. The percentage of specimens containing tubercle bacilli is not stated.

Proskauer, Seligmann, and Croner. Zeit. Hyg., Bd. 57, 1907, p. 173.

Made an examination of the milk sent in from Denmark, comparing it with Berlin milk. The examination was very thorough, including a search for tubercle bacilli by means of animal inoculation. Danish milk: Thirteen specimens examined, 5 found to contain tubercle bacilli (38.5 per cent). There appears to have been a verbal agreement with the contracting parties that the milk furnished should have been heated 80° to 84° C. Berlin milk: Of 9 samples, 5 contained tubercle bacilli (55.5 per cent). However, in five tests of milk from dairies controlled by veterinary inspections no specimens were found to contain tubercle bacilli.

THE NUMBER OF TUBERCULAR COWS IN THE DAIRIES SUPPLYING WASHINGTON, D. C.

A letter was addressed to Dr. W. C. Woodward, health officer, Washington, D. C., and to the Agricultural Department requesting data as to the number of cows in dairies supplying milk to the city of Washington that had responded to the tuberculin test. Dr. J. R. Mohler stated October 4, 1907, that of 1,147 recently tested cows supplying milk to the city of Washington, 214, or 18.6 per cent, responded

to the tuberculin test. He stated that he did not consider this a fair estimate of the extent of tuberculosis in the dairy herds of this vicinity as the tests were only being applied to those herds which had recently been cleansed by private tests or appear so healthy that their owners have no fear of having them tested.

I am informed by the District health department that 1,059 cows, from 51 herds in Virginia, Maryland, and the District of Columbia, supplying milk to the city of Washington were tested for their reaction to tuberculin; of this number 160, or 15.1 per cent of the total number of cows tested, responded to the tuberculin test.

Of course the above figures furnished by the department of Agriculture and the District health department do not give a fair idea of the prevalence of tuberculosis in the herds supplying milk to Washington, as only the owners of those herds who had reason to think that their cows were free from tuberculosis permitted the test to be made. If the test had been applied to all the cows supplying milk to the District I have no doubt that the percentage would be very much higher than the above figures would seem to indicate.

RESULTS OF TUBERCULIN TESTS ELSEWHERE THAN IN HERDS SUPPLYING WASHINGTON.

The following figures by Salmon show the number and percentage of cattle carcasses condemned for tuberculosis during the years 1901-1905 in the meat-inspection service of the Bureau of Animal Industry:

This does not show the total number of animals affected with tuberculosis, for in many cases only a part of the carcass was condemned and probably many had the disease so slightly that the entire carcass was passed as fit for food.

The following table, also taken from Salmon's article, showing the results of the tuberculin test of cattle in some States, is of value as showing the wide distribution of bovine tuberculosis. It must be remembered that most of the herds tested were suspected herds, which may account for the very high percentages found:

a Salmon, D. E.: Bull. No. 38, Bureau Animal Industry, 1906.