366 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



physical. Thns, the butter made from the milk of one breed may be 

 more waxy than butter made in a like manner from milk from a 

 cow of a different breed. The butter made from the large globules of 

 a milk appears to be of a superior grain to the butter made from the 

 small globules of the same milk. Globules of a large size are more 

 easily ruptured through the process of churning than those of a small 

 size, and those of extreme minuteness cannot be ruptured at all. Con- 

 sequently the quantity of butter obtained in practice is not dependent 

 entirely on the amouirt of fat in the milk by analysis, but rests upon 

 the form in which it occurs. By means of a microscopic study of 

 milk, the experienced worker can judge of the butter-value of a milk, and 

 can quickly separate from a herd those cows which produce an unprofit- 

 able milk for the butter-manufacturer. He can also separate those milks 

 which are the least valuable for the cheese-maker from those that are 

 the most valuable. He can also tell to a certain extent what food will 

 make his milk best for his purpose. Of the effect of food upon the 

 yield of butter from milk of different breeds, the writer says : 



The question of the effect of food apon the butter is, therefore, principally a ques- 

 tion concerning nutrition, of the digestibility of food, and of the ability to cause cer- 

 tain constituents of the food to be taken up iu a quantity sufficient for the wants of 

 the animal as determined by structure. When a cow is producing less butter than her 

 structure tits her for secreting, then must an increase of proper food increase her but- 

 ter product. When her food is nnlitted, through its character or condition, to supply 

 the blood with the requisite elements, then must a change of food for the better be 

 beneficially perceived on the butter-yield. We have an individual influence, however, 

 which complicates the action of nutrition, for the superior cow is more a creature of 

 art, the inferior cow more the production of nature, and accordingly the best and 

 poorest cow of a herd being fed with au increased supply of food, in every case the 

 better cow will respond to a greater extent than the poorer. 



The influence of the fats of the food in accelerating digestion and other chemical 

 reactions of the food is of importance in a practical view of the effect of the feeding. 

 It is even probable that the nearer the food given approaches the state in which its 

 elements are found in the product, (if the food be digestible in this state,) the better 

 the result. It is even probable that the presence of certain oils or fats in the food may 

 influence to some extent the proportionate quantity of the separate oils in the butter 

 and the fat. It is but a-s we regard an animal as a whole, and attempt to know her 

 by the study of the history of how she came to be what she is, as well as what she is, 

 that we can form an understanding of the action or product of auy particular part. 

 Wo recognize the formation of butter as allied to the formation of fat, with this essen- 

 tial diftcrence: the fats are formed and stored subject to the order of the animal 

 economy ; the batter is formed and thrown oft', and thus disconnected with the animal 

 structure is nominally subject but to the order of an external being, the calf or the 

 milker. 



The summary of what would be indicated by the theory of the cow and her food is 

 that each cow has a limit to production, governed by structure, and the greatest gain 

 of butter is when her food keeps her to this limit and is not in excess. Second, that the 

 character of the food must influence to a certain extent the cbaracter of the butter, 

 but that in tlie presence of abnndant and similar food, heredity exerts a prepotent 

 influence. The third indication is that the proportion of the butter stands in no 

 definite relation with tlie casein, but that either may be increased within certain 

 limits without a proportionate increase of the other. I call this an indication only, 

 for we have not as yet presented the formation of casein, but will here assume that it 

 arises in the milk tlirough an entirely diflerent process from the butter, and although 

 influenced by structure, yet in a different manner from that in which the butcer 

 element is influenced, and there is accordingly no necessarily direct co-relation between 

 the quantity of these two products. 



A summary of facts indicating the same propositions as our theory is, first, that 

 common experience has shown that one cow is always better than some other cow in 

 a herd, and that no matter what may be the food the yjoorer cow can never, on the 

 same kind of food, and both abundantly supplied, equal in product the better cow. 

 Our second proposition is shown by the experiments of Thomas Horafall, as given in 

 full in the Journal of the Royal Agricultural Society of England, xvii, 260; xviii, 15U. 

 Our third, is the fact that the difference between the butter percentage of various 

 breeds is far greater than is the diftcrence between the case in percentage ; that series 

 of analyses of same milks at different x'c^riods from calving indicate uo ratio between 

 the two. 



