PRODUCTION" OP MILK OF LOW BACTERIAL CONTENT. 



33 



of bacteria introduced, it is a factor of less importance than un- 

 sterilized utensils. Nevertheless, dirt and manure should be kept 

 out of milk, not only to help insure the production of milk of low 

 bacterial count, but also to minimize the possibility of infection by 

 disease-producing organisms, particularly that of bovine tubercu- 

 losis. It has been shown by Shroeder (4) that cattle having tuber- 

 culosis swallow their sputum, so that the tubercle bacilli in it pass 

 through their bodies and into the manure. 



The small-top pail was designed for the purpose of helping to 

 prevent the entrance of manure and. dirt into milk. Many investiga- 

 tions, among which may be mentioned the work of Stocking (5), 

 also Harding (6) and his associates, and Lamson (7), have shown 

 it to be of great assistance in this connection. Throughout the 

 experiments both the open and small-top pails were used, and 

 attention is again called to the value of the small-top pail in 

 the experiments whether the cows were clean or dirty. Table 15 

 gives a summary of the average bacterial counts from milk from the 

 sterilized open and small-top pails. Discussion of the results is 

 unnecessary, as they confirm what has been recognized, namely, that 

 lower bacterial counts can be obt'ained when a small-top pail is used. 

 In all except the last figures in Table 15 the averages represent the 

 counts at the same milking when two cows were milked into open 

 and two into small-top pails. The most interesting point in connec- 

 tion with the figures is the fact that even under extremely dirty 

 conditions relatively low average bacterial counts were obtained. 

 The original cost of a small-top pail is little more than that of an 

 open pail; it is no more expensive to care for and is of distinct 

 value in preventing the entrance of manure and dirt info milk; 

 consequently it should always be used. 



Table 15. 



-Summary of bacterial counts of milk drawn under various conditions 

 into sterilized open and small-top pails. 





Number 

 of samples 

 averaged. 



Bacteria per cubic cen- 

 timeter. 



Condition of cows and barn floor. 



Open pail 

 (steril- 

 ized). 



Small-top 

 paiJ (steril- 

 ized). 



Cows dirty, manure removed once a week 



■ 36 

 41 

 23 

 15 

 32 



22,677 

 86,212 

 6,166 

 4,947 

 8, 681 



17,027 



Cows dirty, manure removed once a week (6 months later) 



24, 439 



Cows dirty, udders and teats clean, manure removed twice a week 



2,886 

 2,667 



Cows clean and bedded, udders not washed, manure removed daily. . . 



i 6, 306 



1 65 samples. 



The value of the small-top pail is well illustrated in Plates I, II, 

 and III, in which a series of sediment disks is shown. The cotton 

 disks show the sediment from milk when a small-top and an open 



