MILK FROM TUBERCULOUS COWS. 
137 
distributed in all parts of the udder if they be present at all. 
Before going on to consider the results of the inoculation 
experiments made with various specimens of milk, it may be 
well to glance at the condition of the cows that have been 
under our control from the time of the beginning of the ex¬ 
periments until they were killed, or until the date of prepar¬ 
ing this paper. 
The history of each cow, as far as we have been able to 
secure it, bears out our assertion—as far as the examinations 
have gone, that none of the udders were affected with tuber¬ 
culosis—certainly so far as gross appearances were concerned. 
This was true also, in the microscopic appearance of every 
case but one (No. 6, Cow F). In this case the gross appear¬ 
ances in the udder were healthy, except that one quarter 
seemed to be slightly fibrous, and there were one or two yel¬ 
low spots which were seen to be made up of fat under the mi¬ 
croscope. With a low power lens only a slight increase of 
fibrous tissue was observable, and the oil-immersion was put 
on merely as a matter of routine. One giant cell was discov¬ 
ered, containing a number of bacilli, but a careful search failed 
to show any others, or any signs of change, except the in¬ 
crease of fibrous tissue as noted above. So that the assertion 
is still true, that we have failed to discover any signs of tuber¬ 
culosis that were easily recognizable in any of the cows here 
recorded, and these include all we have had under close ob¬ 
servation. 
Those from which milk was used for inoculations that are 
not here given had no signs that permitted of even a probable 
diagnosis by skilled veterinarians. 
We also made an interesting series of experimental inocu¬ 
lations in rabbits and guinea pigs with milk or cream from 
various cows, in varying quantities and at different times. Of 
rabbits there were used fifty-seven animals. Of these, five 
were inoculated with milk which had turned sour, two died 
of intercurrent diseases in a few days (coccidium oviforme), 
and of one the material was lost before the microscopic exam¬ 
ination was completed—so that eight animals are to be reject¬ 
ed, leaving forty-nine upon which the results can be based. 
