TUBERCULOSIS OF THE COW 



139 



farm, while the greater part of those reacting in groups A and 

 B had been purchased from outside sources. 



Summary of Tuberculin Tests. 



Group A = 3. group of 7 creameries immediately adjacent to Medina 

 and Oak Park. 

 „ B = & group of 4 creameries near but not contiguous to Medina 

 and Oak Park. 



Of the 184 animals condemned after slaughter as many 

 as 110 showed invasion of lymph glands of body cavity or 

 liver. 



The Pkbvalence of Tubbecle Bacilli in Dairy Pkoduce 



Milk. — The table on page 332 shows the percentage of 

 tubercle bacilli found in a number of milk samples as supplied 

 to a number of the large cities in England. 



The milk supply of the smaller areas appears to be no- 

 better, in fact it is probably infected with tubercle bacilli 

 even more extensively. For example, out of 28 samples of 

 milk supplying Wakefield^ 4 contained tubercle bacilli, a 

 percentage of 14-3. Kanthack and Sladen " examined the 

 milk supply of the different colleges in Cambridge. Milk 

 from 16 dairies was examined, 3 specimens being collected 

 from each. Nine of the 1 6 dairies showed tubercle bacilli in 

 the milk, as demonstrated by guinea-pig inoculations. 



Investigations in other countries show an equally high 

 percentage of tubercle bacilli in market milk. In Washington ^ 



1 Medical Officer, Sept. 3, 1910. 



2 Lancet, 1899, vol. i. p. 74. 



3 Bulletin No. 4-1, Public Health and Marine Hospital Service, U.S.A., 

 1908, p. 191. 



