MAIS-UAL OF CATTLE-FEKDIRa. 431 



Even tlie milk drawn at different lionrs of tlie day from 

 tlie same cow is by no means always of the same quality. 

 Tlie longer the time from one milking to another, the more 

 watery is the milk ; so that if the cowb are milked three 

 times daily, the morning milk is more watery than the 

 noon or evening milk. 



Still more striking are the differences observed in dif- 

 ferent portions of milk from the same milking. The 

 milk w^hich is first drawn from the udder is always far 

 more w^atery and poorer in fat than the last portions 

 drawn. 



These circumstances, of course, nnist all be taken into 

 account, and the possible errors arising from them avoided 

 in any experiments upon the effect of feeding on the 

 quality of the milk. This can only be done by extending 

 the observations over a considerable time, and making a 

 large number of milk analyses. Kesults based on but a 

 small number of analyses, or covering but a short period, 

 are to be accepted wdth great caution. 



^4. The Feeding Standard. 



The Nutritive Ratio. — ^All experiments on milk cows 

 agree in showing that an abundance of protein in the 

 fodder is an essential condition of the maximum produc- 

 tion of milk. This implies a rather narrow nutritive 

 ratio, since otherwise the quantity of protein in the amount 

 of fodder which could be eaten would be too small. 



It is true that a large supply of protein and a narrow 

 nutritive ratio tend to increase the protein consumption in 

 the body, and for that reason the nutritive ratio must not 

 be made too narrow. At the same time, there is less fear 

 of this effect with milking animals than watli others, be- 

 cause much of the protein goes to sustain the activity of 



