136 Effect of External Influences. 



stituted. Backhaus observed an increase of milk and fat con- 

 tent after the introduction of an automatic water supply. 



Milk of poor quality is known to have resulted from the use 

 of poor drinking water. Stagnant waters give the milk a repulsive 

 taste. 



Taken as a whole all foods and all food mixtures which are par- 

 taken of and digested by the animals without disturbance in their 

 general condition are adapted to the feeding of milk animals. Food 

 which in continuous feeding causes diarrhea or other intestinal 

 disturbances should be avoided. Intestinal disturbances which 

 quickly subside and which sometimes develop as a result of sudden 

 change of food are of no consequence in the judgment of the food. 

 They may cause considerable fluctuation in the yield of milk and 

 fat content, which however subsides in a few days. From the 

 above statement it will be seen that under certain conditions, espe- 

 cially when a heavy production of cream is necessary, the effects 

 of a change of food must be considered. If, when considering 

 evidence of adulteration, methods of examination are used which 

 take note of the approximately constant factors in milk, that is, 

 such as pertain to the protein-free milk serum, the influence of a 

 feeding method, or a sudden change of feed should be taken into 

 consideration in regard to its effect upon the milk of each indi- 

 vidual animal. 



Spoiled food injures the taste and odor of the milk and 

 butter, and its effects may last for a long period after the time of 

 feeding such food. The feeding of large quantities of beet or tur- 

 nip tops should be guarded against, likewise over feeding with 

 fresh or sour chopped roots, potato slops, residues from starch 

 factories, brewer's grains, rape seed cake, flaxseed meal and poor 

 straw. 



The taste is improved by feeding on pasturage, red clover, 

 meadow grass, carrots, oats and rice flour. 



Firm tallowy butter is derived from grass of acid soil, from 

 grass from fall pastures, late hay made from sour grasses, leaves 

 of sugar-beets, or red beets, chopped roots, potatoes, peas, palm 

 seeds, cocoanut and flaxseed cake, and cotton-seed meal. 



Soft butter results from the feeding of oat hulls, corn bran, 

 wheat bran, rice flour, rape-seed cake and sunflower-seed cake. 



Clover pastures are not suitable for the production of milk for 

 cheese making since the cheese becomes permeated with small holes, 

 and has a sharp repulsive odor. This condition is probably brought 

 about by bacteria which vegetate on the clover plants of the 

 pasture. 



Changes from one feed to another should not be made too sud- 

 denly if it is desired to prevent an effect on the milk production. 

 Newly introduced food substances should not be fed in large 

 quantities at first. In changing from dry food to pastures a dimin- 

 ished milk yield first results, then a period of normal yield and 



