Page:Popular Science Monthly Volume 48.djvu/823

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PRACTICAL RESULTS OF BACTERIOLOGY.
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inoculation. 3. Number of animals dying within twelve days after the second inoculation. 4. Number of animals dying of anthrax within a year after protective inoculations. 5. The yearly average loss before inoculations were practiced. The total number of animals inoculated during the period to which this report refers was 1,788,077 sheep and 200,962 cattle. The average annual loss before these protective inoculations were practiced is said to have been about ten per cent for sheep and five per cent for cattle. The total mortality from this disease among inoculated animals, including that resulting from the inoculations, was 0·94 per cent for sheep and 0·34 per cent for cattle. Chamberland estimates that the total saving as a result of the inoculations practiced has been five million francs for sheep and two million francs for cattle.

Podmolinoff gives the following summary of results obtained in 1893 and 1893 in the government of Kherson (Russia): Number of sheep inoculated, 67,176; loss, 294 = 0·43 per cent. Number of horses inoculated, 1,452; loss, 8. Number of cattle inoculated, 3,652; loss, 2. The conclusion is reached that Pasteur's method of inoculation affords an immunity against infection with virulent anthrax bacilli in greater amounts than could ever occur under natural conditions.

Another disease in which inoculations have been practiced on a large scale is erysipelas of swine (rouget of French authors), which prevails extensively in France and other parts of Europe.

Pasteur's first studies relating to the ætiology of rouget were made in collaboration with Chamberland, Roux, and Thuillier in 1882. Pasteur found that the virulence of his cultures was increased by passing them through pigeons and diminished by passing them through rabbits. By a series of inoculations in rabbits he obtained an attenuated virus suitable for protective inoculations in swine. In practice he recommended the use of a mild virus first, and after an interval of twelve days of a stronger virus. These inoculations have been extensively practiced in France, and the fact that immunity may be established in this way is well demonstrated.

In a paper published in 1894 Chamberland states that in the preceding seven years, during which time protective inoculations had been practiced in France on a large scale, the mortality from rouget had been reduced to 1·45 per cent, whereas before these inoculations were practiced the mortality from this disease was about twenty per cent.

Hutyra has given the following statistics of inoculations made in Hungary during the year 1889 with "vaccines" obtained from the Pasteur laboratory in Vienna: 48,637 pigs were inoculated on 117 different farms. Of these, 143 (0·29 per cent) died between the