252 



Nature-Study Agriculture 



Differences 

 in richness 

 of milk 



Butter fat 



Holstein- 



Friesians 



compared 



with 



Jerseys 



squarely built as compared with the more slender dairy 

 cattle. Their food is used in putting on flesh rather 

 than in making milk. They give only about enough 

 milk to support their calves. Dairy cows with their 

 calves could not be allowed to run loose for months at 

 a time on the Western ranges as beef cattle do without 

 being milked, for their calves could not take all the 

 milk, and the cows would suffer. Some dairy cows must 

 be milked three times a day. 



Dairy cows do not all give milk of the same quality. 

 Jerseys give much richer milk than Holsteins. By 

 " richness " is meant the amount of butter fat which 

 the milk contains. By setting two bottles of milk side 

 by side and allowing them to stand for one or two days, 

 it is easy to see which has the more cream. This is 

 only a rough test, however, for different samples of 

 cream may have different amounts of milk mixed with 

 them. Cream may contain anywhere from ten to sixty 

 per cent of pure " butter fat." Tests have shown that 

 the amount of butter fat in milk from different .cows 

 may vary from about three to six per cent; that is, 

 some cows give milk twice as rich as others do. 



The Holstein-Friesians unquestionably produce milk 

 in larger quantities than do cattle of any -other breed 

 (Fig. 201). As compared with the Jerseys, the quantity 

 of milk they give is almost double, but in richness it 

 falls far short of Jersey milk. Average Jersey milk is 

 about four and a half or five per cent butter fat, whereas 

 that of a Holstein cow averages about three and a half 

 per cent. As butter producers they rank fully as well 

 as Jerseys, however, because the larger quantity of milk 



