176 PRINCIPLES AND PRACTICE OF MILK HYGIENE 
the hay or fodder is thrown down directly into the stable 
from a loft above, the quantity of dust set free in the 
stable air is much greater than when it is thrown down 
into a passageway outside of the stable. Feeding meal 
or ground grain immediately before milking is also objec- 
tionable, and for the same reason. It is not necessary to 
feed cows before milking to keep them quiet during milk- 
ing; they soon become accustomed to being fed after 
milking. 
The investigations of Ruehle and Kulp’ indicate that 
under ordinary conditions dust in the stable air is not 
nearly as much concerned in the bacterial contamination 
of milk as has been generally believed, but as it is only 
necessary to perform the several stable operations in a 
certain order, and does not require additional labor, to 
protect milk against this source of contamination it is 
advisable to take this precaution, especially since un- 
usual conditions which will increase the infection from 
this source are likely to prevail at times. 
The feeding of ensilage fills the air of the stable for 
a time with the odor characteristic of this substance, and 
if milking is done during this period the odor and taste 
of the milk is likely to be tainted. This is likewise true of 
cabbage and rape, and also of beets, turnips, rutabagas 
and carrots, and their tops (see page 29). Odors in the 
stable are very quickly absorbed by milk, especially when 
it is warm. 
Sudden changes of feed and overfeeding should be 
avoided. A sudden change from dry to green feed will 
produce diarrhoea. Old and highly acid ensilage and 
sometimes overfeeding will have the same effect. Indi- 
1 Geneva, N. Y., Expt. Sta. Bull. No. 409. 
