21 



were fed almost entirely with milk, this food was doubtless the 

 source of infection. 



In the case of swine which are largely fed with skimmed milk, 

 whey, or butter-milk, the '' feeding turberculosis " takes an impor- 

 tant part. 



Tuberculosis in horses is not rare in Denmark, doubtless because 

 of the extended use of milk in fattening young horses intended for 

 market. This usually appears as '* feeding tuberculosis," with intes- 

 tinal ulcers and very large deposits in the mesenteric glands, some- 

 times also in the peri-pharyngeal glands, or with secondary deposits 

 in the lungs. 



Tuberculosis investigations have made it highly probably that the 

 cooperative dairies often contribute to the spread of the disease. 

 The patrons receive in return skimmed milk for feeding calves and 

 swine. It is understood of course that they do not receive their own 

 milk but a part of the mixed milk. In case the milk of another 

 patron comes from a tuberculous cow the danger is at hand that in 

 this manner the disease may be communicated to a healthy herd. 

 That this actually happens is proved by the common observation that 

 all grown cattle of a herd may be found healthy, while various calves 

 and heifers react. Fortunately skim-milk is almost everywhere 

 sterilized before being distributed, but it is frequently not heated to a 

 suthciently high temperature. Since I called attention to this danger 

 which is involved in the otherwise useful cooperative dairies these 

 conditions have gradually improved. I hope it will not be long 

 before all skim-milk will be heated to 80" C (185" F) before 

 being used. From the observations described it must be apparent 

 that infected milk has much to do with the spread of tuber- 

 culosis. By cooking or warming at high temperature, sure protec- 

 tion may be easily obtained. The calf, however, can scarcely 

 dispense with the colostrum during the first day of its life, but from 

 the second day, cooked milk is easily digested. At Thurebylille, I 

 have fed all calves very successfully with cooked milk from the 

 second day on. The colostrum is warmed to 65^ C (149° F). This 

 temperature does not, indeed, kill tubercle bacilli, but weakens 

 somewhat their virulence. Not much importance is'laid on this 

 heating of the colostrum. Probability of an infection through the 

 use of the raw material for one day is evidently not very great. 

 Moreover in this wav a tuberculous cow can onlv infect one calf and 



