AGRICULTURAL EXPERIMENT STATION. 



125 



Average Composition for One Year of the Skimmed Milk, 

 Cream and Butter Milk. 



0/ 0/ 



/o /o 



9.41; .29 



10.12 .56 



10.70 l.M 



10.46 .24 



Ifia 1 10.96i .67 



Jansje 



Nancy Avoudale. 



Queen Linda 



Agnes 



tjkiinuied 

 Milk. 



Cream. 



/o 

 23.75 



24.70 

 24.37 



27.42 

 27.68 



/o 

 16.13 

 16.79 

 16.21 

 19 20 

 19.39 



Bntter Milk. 



0/ 



/o 



9.68 

 10.05 



9.95 

 10.37 

 10.. 50 



/o 



.4S 

 .47 

 .34 

 .17 

 .19 



There has prevailed somewhat generally the opinion that the 

 skimmed milk of Jersey cows is of poorer quality than that of the 

 Ayrshires or other breeds whose milk is not so rich in fat. That 

 opinion is not sustained by these analysis, the Jersey skimmed 

 milk proving to contain a higher per cent, of solids than that of 

 the other two breeds. The same is true of the butter milk. 

 Except for the first month or so, there is a gradual increase in the 

 solids of the skimmed milk and butter milk up to parturition. 



The average percentage of fat in the skimmed milk varies great- 

 ly, being least with one of the Jerseys, and largest with one of 

 the Ayrshires. It is true, however, that during the time of a full 

 flow of milk the percentage of fat in the skimmed milk of the 

 Ayrshires were much larger than in the case of the other breeds, 

 the Jerseys showing the instances of the most complete separation. 

 It is true of all the cows without respect to breed, that the per- 

 centage of fat in the skimmed milk, or in other words the waste 

 of fat, increases in a marked manner as the period of milking 

 lengthens and parturition approaches. 



The butter milk of the Jersej^s shows least fat, the percentage 

 being onl}^ about half tliat of the oiher cows. 



Later will be given the percent-ige of the total fat of each cow 

 which passes off in the waste products, when the relative loss will 

 be more clearl}' seen. 



The analyses of the cream coincide with the churn tests in show- 

 ing the Jersey cream to be considerably richer in fat than that 

 from the other breeds. Again while the cream grows richer in solids 

 as the period of lactation lengthens and parturition approaches, 

 (which is also true of the milk.) the percentage of fat does not in- 

 crease but rather diminishes. The following figures show that 

 this increase in solid matter falls upon other constituents of the 

 cream than upon the fat, which is equivalent to showing that the 

 fat in the milk of cows approaching parturition separates from 

 the casein, etc., less readily and therefore less completely than in 

 the early stages of the milking period : 



2-M 



