208 DAIRYING. 



YIELD OF MILK AND FAT FROM DAIRY COWS. 



A good dairy cow should give at least 5000 pounds ol 

 milk during a whole period of lactation. As the quality 01 

 milk given by different cows varies greatly, however, as 

 will be apparent from the tables given in the following, the 

 yield of fat produced during a lactation period is a better 

 standard to go by than that of the milk; three-fourths of a 

 pound of tat per day for an average of 300 days may be con- 

 sidered a good yield (total 225 pounds). Many dairy farmers 

 aim to have all mature cows in their herds produce a pound 

 of fat, on the average, for every day in the year. To do 

 this, a cow whose milk tests about 4 per cent, must give 25 

 pounds of milk a day (3 gallons) as an average for the 

 whole year; a cow producing 3 per cent milk must give 33^ 

 pounds of milk daily, and one producing 5 per cent milk 

 must yield 20 pounds of milk daily, on the average, etc. 



The flow of milk is usually at its highest shortly after 

 calving, and then gradually decreases, the rate of decrease 

 being determined by the inbred milking qualities of the 

 cow and the system of feeding practised. The average de- 

 crease in milk yield for good dairy cows on good feed is 

 from one half to three fourths of a pound per head per ten 

 days. Where cows are not fed liberally and receive but lit- 

 tle concentrated feed, the decrease will be more marked, 

 and often exceed one pound of milk per head per ten days. 

 The decrease is more marked during the latter stages of 

 the period of lactation than in the earlier ones, and is also 

 more marked in cows with poorly developed milking qual- 

 ities than in good dairy cows. A cow is considered at her 

 best when from five to seven years old; the constitutional 

 strength of the animal, the system of feeding practised, 

 and the general treatment given the cow will determine 

 her period of usefulness. 



The quality of the milk produced by individual cows 

 generally remains fairly uniform through the greater por- 

 tion of the lactation period, and is not permanently influ- 

 enced in any marked manner by feed or any external 

 conditions. During the last couple of months, when the 



