MILK 11 



Gases. The gases dissolved in milk are oxygen, nitrogen, and carbon 

 dioxide; they are probably absorbed during and after milking. Decom- 

 posed milk often contains stinking gases that are derived from the 

 breaking down of the proteins which contain sulphur. 



Composition and Flow of Milk Variable. There are many factors 

 that influence both the amount of milk flow and the composition of milk. 

 It is important to realize this for the variations are not ordinarily appar- 

 ent to our senses which fact has fixed in the minds of most of us the unfor- 

 tunate belief that the variations are of minor importance, that milk is 

 milk, and that its production involves little skill and forethought. In 

 truth, the differences in milk are considerable and the sound management 

 of a dairy herd requires much intelligence as well as thorough training 

 and experience. 



Effect of Maltreating Cows. At the outset it may be said that the 

 milk business is founded on motherhood and that the dairy cow is a 

 high-bred, nervous animal so that it is imperative that she have consider- 

 ate treatment. Cruel and abusive usage of the animals is no part of 

 good dairying and the farmer who curses, beats or dogs his cows is sure 

 to have to pay for it because such acts adversely affect both the quantity 

 and quality of milk yielded. 



Factors Influencing the Milk Flow. A number of things affect the 

 milk flow. Certain breeds of cows and certain individual animals are 

 heavy producers; it is their nature. A cow at different ages yields 

 differently; Eckles, after careful study, reached the conclusion that on 

 the average a dairy cow may be expected to produce about 70 per cent, 

 as a 2-year old, about 80 per cent, as a 3-year old and about 90 per cent, 

 as a 4-year old of the milk and butterfat that she will produce when 

 mature. The richness of the milk remains practically constant except 

 that after the third milking period there is. a slow, gradual decline with 

 advancing years. The size and character of the ration affects the 

 amount of milk given and its character in less degree. Almost any change 

 in feed has a slight temporary effect on the quality of the milk but if 

 the ration is sufficient, the quality of the milk cannot be markedly or 

 permanently altered in this way. Fat cannot be fed into milk but the 

 quality of the butterfat is affected by certain feeds; for instance, linseed 

 oil meal and gluten meal make a soft oily fat while cottonseed meal, 

 wheat bran and some other feeds make hard fat. The milk flow is re- 

 duced in quantity by spells of heat and drouth as it is temporarily in 

 cold snaps and if the cows are exposed to cold wet storms. 



Effect of Milking. The frequency and manner of milking affect both 

 the quantity and quality of the milk. If a cow is milked three or four 

 times a day she will produce more milk, but with greater fluctuations in 

 the percentage of butterfat in the milk at the different milkings, than if 

 she is milked but twice. Cows that are making a record of production 



