DAIRY FARMING — DAIRYING. 



341 



the height of the milk pail aud in close proximity to the same while 

 the milking is in progress. The results of some of these experiments 

 are summarized below: 



Effect of icxshiufj udder on the bacteria in milk. 



November 6 . . 



November 10 



November 24. 

 February 20 . 



March 3 



August 23 



Date. 



Treatmeut of cows. 



Stabled . . 



do ... 



do... 



do... 



do... 



do ... 



Pastured 



Estimated number 

 of bacteria de- 

 posited per min- 

 ute on 78 sq. in. 

 of surface (10- 

 iuch milk pail.) 



Ordinary 

 condi- 

 tions. 



16, 400 

 4,010 

 1,700 

 4,165 

 1,800 

 2,700 

 3,260 



Udder 

 and flank 

 washed. 



2,600 



1,860 



560 



1,370 



1,300 



330 



114 



Reduc- 

 tion of 

 organ- 

 isms. 



Per cent. 

 85 

 54 

 66 

 69 

 27 

 88 

 96 



During the last trial the germs due to those floating in the air were 

 checked by exposing a plate to the air under similar conditions. 



"While 114 germs were deposited under the cow, 65 were found on the plate exposed 

 simply to the air. The extent of diminution is therefore really greater than would 

 appear from the foregoing table." 



In feeding hay, straw, or coarse dry fodder the barn air is much 

 infected witii dust particles to which bacteria are attached in large 

 numbers. A gelatin plate exposure made in the stalls during the feed- 

 ing showed that over 160,000 organisms were deposited in a minute on 

 an area covered by an ordinary milk pail. 



" These settle with tlie dust, and in doing so inevitably gain access to the open milk 

 vessels. In this Avay the hay bacillus and allied forms that are of a resistant char- 

 acter find their way easily into the milk. This source of danger can be eliminated 

 by feeding moistened feed during the milking, or the dry feed immediately subse- 

 quent to this operation but after the milk has been removed from the stable." 



It is stated that by observing the precautions as to cleanliness men- 

 tioned above " the keeping quality of the milk may be increased to 

 such an extent that it will remain sweet from 24 to 48 hours longer 

 than it otherwise would." 



"The following example shows to what extent the bacteria of the milk can be con- 

 trolled by rational methods of milking: In October the mixed milic taken in the 

 ordinary way was found to contain 15,500 germs jier cubic centimeter, while the 

 average of the total yield of a cow that had been carefully cleaned and the milking 

 done in the manner already suggested contained only 330 bacteria for the same vol- 

 ume. In February, imder winter conditions, a rei)ctition of tlie same experiment 

 revealed a. still smaller number, there being 7,G!^0 germs per cubic centimeter in the 

 mixed milk, while that received in open sterile pails, but with greater care, had 

 only 120 bacteria for the same volume. . . . 



"At room temperature there was a difference of 24 hours in time before both 

 soared in favor of the milk secured with this extra care." 



8708— No. 4 (i 



