TUBERCULOSIS IN CATTLE. 61 
gradual exclusion of the non-reacting herd. The farmer will, 
of course, seek to get rid of the animals in the reacting herd as 
rapidly as he can do this without loss, and in time the reacting 
herd will probably very largely disappear. All of this will, 
of course, hasten the reduction of the number of reacting 
animals. 
It must not be understood that the conservative recom- 
mendations that have been here suggested are universally 
agreed upon by bacteriologists or veterinarians in Europe or 
elsewhere as sufficient. Very much more drastic measures are 
frequently suggested and advised. There are still those who 
insist that all animals reacting from tuberculin should be 
slaughtered ; that under present conditions of things it is un- 
safe to use the flesh of such animals under any conditions, that 
slaughter-house inspection cannot be enforced sufficiently to 
make it safe; and that it is absolutely unsafe to recommend, 
even tentatively, the use of the milk of animals that have re- 
acted to the tuberculin test. It is pointed out, and of course 
properly pointed out, that it is impossible to tell when such a 
reacting animal may acquire tuberculosis in the udder, and, 
even though at the time of inoculation the disease may be in- 
cipient and the milk healthful, it is perfectly possible that at 
any minute the disease may become located in the milk gland 
and the milk become contaminated. These are, of course, 
undoubtedly, facts, and tend to increase the question as to 
how safe it is to use raw milk of reacting animals, even under 
any conditions. Nevertheless, the present indications that the 
number of cases of tuberculosis as derived from milk is so 
small, and the almost universal opinion that such cases are 
confined to children, lead to a growing belief that the milk of 
reacting animals may be used, if precautions are taken to en- 
sure its pasteurization or its sterilization, for use by infants. 
III. PRACTICAL CONCLUSIONS. 
There are several practical conclusions to be drawn from the 
facts as they have been pointed out in the previous pages, and, 
while these conclusions have already been mostly indicated, a 
summary of the more important may not be out of place. 
If a farmer owns a herd free from tuberculosis he wishes to 
know how to preserve it in this condition. His only sure 
