130 ILLINOIS STATE DAIRYMEN'S ASSOCIATION. 



The cows should be kept clean at all times, and this is not difficult to 

 do, if the mangers and ties are properly arranged, the stall of the right 

 length and a fair amount of bedding used. All loose dirt should be 

 brushed from the cows and the udders washed and wiped before milking, 

 whether they seem dirty or not. 



The dairy department of the University of Illinois has been investigat- 

 ing the source of milk contamination, and how it may be avoided in actual 

 practice. Several hundred plates have been exposed in the University and 

 other dairy barns and a few of the results are given below, each of which is 

 an average of ten exposures. These plates are glass dishes Zy 2 inches in 

 diameter and having a glass cover fitting closely over the sides. The 

 empty dishes are sterlized by baking in a hot oven over twenty minutes, 

 then sterlized beef-broth containing a little gelatin is poured over the bot- 

 tom, and when this cools it solidiies. These closed sterilized dishes hav- 

 ing twelve square inches of surface are then taken to the dairy barn, and 

 exposed by removing the cover one-half minute. The bacteria floating on 

 the dust in the air settles into the dishes. The covers are again replaced 

 and the dishes held at a warm te?nperature for two or three days. Wher- 

 ever a bacterium has fallen it will commence to multiply until a colony 

 forms which can be seen with the naked eye. 

 Placed Exposed. No. Bacteria Caught. 



Under apparently clean unwashed udder 2023 



Undersame udder after washing 90 



It will be seen from this that the contamination the milk received 

 from an apparently clean udder is very great and that it may be reduced 

 by washing over 95 per cent. 



SECOND, THE STABLE.— Often the sides of the stable and stalls are 

 plastered with dung, and not cleaned for years at a time. Frequently the 

 old bedding in the stalls and refuse in the mangers are not thoroughly 

 removed from one year's end to another, leaving a quantity of dust to be 

 frequently stirred up. Bedding and dry fodder should not be moved just 

 previous to milking as it makes a dust which settles into the milk, carrying 

 with it many bacteria. The air outside is usually comparatively free 

 from germs, and the better ventilation the barn has the fewer germs will 

 the stable air contain. If the cows are in the stable the greater part of 

 the time the stable should be cleaned twice a day. The ceiling should 



