11 



THE PREPARATORY RATION, 



or ration (i), contained mixed hay and oat fodder. The variation 

 of the volatile acids and iodine number, due to other causes than 

 food, may be seen in the table, along the first line. 



Vetches (3) and oat fodder (5) were tried but once in each case. 

 The former was fed to group II after (1) and the latter was fed to 

 group IV in the same order. Neither produced any apparent 

 change in volatile acids. Clover hay (2) was fed to groups I and 

 IV, and in each case the volatile acids were increased, which is con- 

 trary to the observed facts for progress of lactation, and should be 

 attributed to the food. In the case of group IV there appears to 

 be but a very slight increase, but in a month the advance of lacta- 

 tion usually lowers the volatile acids appreciably. 



Mixed hay (4) was fed to groups I and III. With group III it 

 followed the preparatory ration and increased the volatile acids \ with 

 group I it followed clover hay (2) and kept the volatile acids at 

 the high point to which the clover hay had raised them. 



Rations (6) and (7) caused no appreciable change in the compo- 

 sition of the butter-fat from the previous rations, unless the con- 

 stancy of volatile acids with group II is considered equivalent to 

 an increase, which may be attributed to the mixed hay. 



Iti general, since the oat fodder was fed in the preparatory ration 

 and in (5), it appeared in this series that it caused a lower amount 

 of volatile acids in the butter-fat, than was the case with clover hay 

 or mixed hay. 



The sinking of volatile acids and rising of the iodine number 

 with the advance of lactation, was again seen in this series in the 

 last period, where the two samples of butter were taken with an 

 interval of two weeks between them. Group III was an exception 

 in the case of the volatile acids. 



There is to be noted in conclusion that some of the results of 

 this scientific investigation are in accord with the practice of many 

 dairy-men who produce a high grade of butter. A favorite ration 

 with them is corn meal and clover or mixed hay. 



Corn meal has been shown to produce a butter-fat with a low 

 iodine number, corresponding to a hard, firm butter. Clover hay 

 and mixed hay have produced a butter-fat with a high figure for 

 volatile acids, which is equivalent to a high flavor. 



Nevertheless, corn meal and clover hay are not the only suitable 

 foods for producing a firm, highly flavored butter, and the study 

 of this bulletin should show other combinations even better. 



