April 1908. j 



345 



Live Stock. 



4. The other two experimenters also 

 contracted the disease, but in their case 

 the eruptions were confined to the 

 mouth. 



5. The precise nature of the virus of 

 foot-and-mouth disease has not yet been 

 elucidated. Some years ago various 

 bacteria were isolated from the lesions 

 and the blood of the affected animals, and 

 each bacterium was claimed by its 

 respective discoverer as the causal 

 agent ; but it has recently been shown 

 that the liquid contents of the vesicles 

 of this disease retain their viruleuce 

 after large dilution with water and 

 passage throutrh a filter, the pores of 

 which are so minute as to prevent the 

 transmission of the smallest known 

 bacteria. It is, therefore, probable that 

 the true causal agent is not within the 

 range of the existing powers of micros- 

 copic vision. 



Tuberculosis. 



6. Another disease communicable to 

 man from the lower animals is Tuber- 

 culosis. It is caused by the tubercle 

 bacillus which was discovered by Koch. 

 The relation between human and bovine 

 tuberculosis is a subject of vital impor- 

 tance. But it is strange that there has 

 recently been a good deal of difference 

 of opinion regarding it. 



7. Koch himself held the opinion that 

 human tuberculosis was entirely different 

 from bovine, and could not be trans- 

 mitted to cattle, and that the infection 

 of human beings from bovine tuberculosis 

 rarely occurred, if ever. 



8. On the other hand, there are ex- 

 perts who believe in the essential 

 identity of both types of the disease, 

 and say that there is only one tubercle 

 bacillus, and that its pathogenic proper- 

 ties are determined by its habitat and 



by the tissues and fluids in which it has 

 developed. 



9. Dr. Nathan Raw, an eminent 

 specialist, holds an opinion which may 

 be called the mean between these two 

 extremes. He says that the bacillus of 

 human tuberculosis and that of the 

 bovine disease are different varieties of 

 a commou species, and that bovine tuber- 

 culosis is frequently communicated to 

 human beings both by means of infected 

 food and by contagion. 



10. As to the particular lesions in the 

 human body produced by these two 

 varieties of the tubercule microbe, he 

 thinks it probable that phthisis pul- 

 monalis and ulceration of the intestines 

 and abdominal glands are produced by 

 the bacillus of the human type and 

 tubercular peritonits, tuberculosis of the 

 lymphatic glands, tubercular meningitis 

 and lupus by the bovine bacillus. 



11. When there is such a divergence 

 of opinion, it is best to err on the side of 

 prudence with regard to the sanitary 

 measures adopted for the prevention of 

 the disease ; and the recent Royal Com- 

 mission on Human and Animal Tuber- 

 culosis, after numerous experiments and 

 exhaustive examinations of the lesions, 

 have come to the conclusion that the 

 tuberculosis set up by the bacillus of 

 human source is, so far as its anatomical 

 and histological features are concerned, 

 one and the same as the tuberculosis set 

 up by the bacillus of the bovine source. 



12. They have further arrived aG the 

 conclusion that cattle and man can be 

 reciprocally infected, and urge the 

 necessity of more stringent measures 

 being enforced to prevent the sale and 

 consumption of milk from cows affected 

 with tuberculosis. 



E. T. HOOLE, 



Acting Govt- Veterinary Surgeon. 



44 



