SIGNIFICANCE OF COLON COUNT IN MILK. 
25 
hours at the same temperature the average count was about 205,- 
000,000. The difference in the rate of growth of organisms of the 
colon-aerogenes group at this temperature seems to vary somewhat 
with the amount of initial contamination, as is shown by the colon 
counts of the fresh milk and after 6 and 24 hours. Further obser- 
vation of Table 14 shows that when the milk was held at 50° F. 
(10° C.) there was little or no increase over the count in the fresh 
milk. There are, however, a few samples which show a distinct 
growth. 
Table 14. — Influence of conditions of production on the subsequent increase of organisms 
of the colon-aerogenes group. 
Total 
Colon count. 1 
Sample 
No. 
Conditions. 
count in 
fresh 
Held 6 
hours at 
86° F. 
(30° C). 
Held 24 hours at — 
milk. 
Fresh. 
50° F. 
(10° C). 
86° F. 
(30° C). 
1 
f 27, 000 

200 

290,000,000 
2 
58,000 
100 
400 

294, 000, 000 
3 
54,000 
100 

100 
126,000,000 
4 
83, 000 

100 

11,900,000 
5 
28,000 



550, 000 
6 
96, 000 



14,200,000 
7 
11, 800 



38,000,000 
8 
39, 000 

100 

2,400,000 
9 
21,600 



1, 700, 000 
10 
12, 400 



5,300,000 
11 
Barn dirty, cleaned twice a week; 
10, 200 

100 

139,000,000 
12 
utensils sterilized. 
22, 000 



11,500,000 
13 
12,500 



1, 100, 000 
14 
42,000 
100 


250, 000, 000 
15 
16, 400 

( 2 ) 

6,300,000 
16 
22, 800 

( 2 ) 

42,000,000 
17 
24, 000 

( 2 ) 

12,400,000 
18 
37, 000 

( 2 ) 

17, 600, 000 
19 
13, 500 

( 2 ) 
300 
8,600,000 
20 
57, 000 

( 2 ) 

54, 000, 000 
21 
14,200 
400 
( 2 ) 
100 
37,000,000 
22 
I 15,500 

( 2 ) 

28,600,000 
Av( 
jrage 
32,477 
! 
63,279,545 
1 
f 1,320,000 



60,000,000 
2 
790, 000 

400 
100 
450,000,000 
3 
1,600,000 



1,900,000 
4 
295,000 

500 

330,000,000 
5 
1, 940, 000 

200 

2,800,000 
6 
690, 000 
100 
300 

7,500,000 
7 
1.310,000 

1,400 

650,000 
8 
520,000 
100 
4,500 

248,000,000 
9 
750, 000 



11,400,000 
10 
460, 000 
100 
2,600 

510,000,000 
11 
320, 000 

( 2 ) 

9,400,000 
12 
13 
14 
Barn dirty, cleaned twice a week; 
440, 000 
400 
( 2 ) 
800 
260, 000, 000 
■ utensils washed immediately but 
not sterilized. 
180, 000 
490, 000 



900 

1,100 
46,000,000 
285,000,000 
15 
318,000 

1,000 

210,000,000 
16 
497, 000 

1,200 
100 
480, 000, 000 
17 
580, 000 

( 2 ) 

174,000,000 
18 
440, 000 
200 
( 2 ) 
100 
216,000,000 
19 
780,000 
100 
2,400 
100 
420,000,000 
20 
710, 000 
800 
46,000 
600 
525,000,000 
21 
590,000 
100 
8,600 
( 2 ) 
580,000,000 
22 
310,000 
900 
41,000 
( 2 ) 
430,000,000 
23 
190, 000 

800 
100 
55,000,000 
24 
230,000 
300 
74,000 
15, 100 
400, 000, 000 
25 
182,000 

1,100 
100 
152, 000, 000 
26 
340,000 
900 
48, 000 
900 
244,000,000 
Av( 
>rage 
625, 846 
10,677 
234,948,077 
■ — 
1 indicates no organisms of the colon- 
3 No determinations made. 
aerogenes group in 1/100 of a cubic centimeter of milk. 
