104 



EXPERLMEXT STATION, 



[Jan. 



The above figures represent the average of five-day composite 

 samples of the milk prochiced by the herd of nine cows while on 

 the two different rations. Samples of each cow's milk were also 

 tested five days in each week for total solids and fat. The aver- 

 age of the two herds by this method varied less than .1 per cent, 

 from the above figures. It is, therefore, evident that the differ- 

 ence in the amount of protein in the ration did not vary the 

 fat, solids not fat, nitrogen or ash content of the milk. 



Expcrimp.ni VI. — lOOo-OG. 



This experiment, hitherto not reporte<:l. was carried out by 

 the group method, six cows constituting each of two groups. 



The object of the experiment was to note the effect of a ration 

 low in digestible protein, — the amount required in the milk 

 ])lus that for maintenance, — as compared with one containing 

 a])])roximatcly ^/o pound in excess. The effect of the tAvo rations 

 was to be noted (a) on the condition of the animals; (h) on the 

 yield of milk, milk solids, fat and nitrogen; (r) on the relative 

 shrinkage; (d) on the composition of the milk. 



Plan of the Experiment. — The twelve cows were divided 

 as evenly as possible into two groups. The first few weeks 

 both groups received the low-protein ration in order to establish 

 a basis for comparison. The record of the milk yield and its 

 composition is reported for the last week of this preliminary 

 period. At the beginning of the period proper, Group TI. re- 

 ceived the high-protein ration, and Group I. continued on that 

 low in protein. 



Hktory of the Cows. 



