342 FEEDS AND FEEDING 



gross income from their herd would be reduced by weeding out the 

 "boarders," their net profits would be materially increased. 



Tho good producers are usually of the dairy type and poor producers 

 are not, even experts are often unable to tell from appearance whether 

 a cow is profitable or not. The only reliable way of finding this out is 

 from records of the actual amount of milk and fat she yields. Fortu- 

 nately, such records may now be easily secured by the use of the milk 

 scales and the Babcock fat test. Knowing the production of each cow 

 and the approximate amount of feed she has consumed in a given period, 

 the dairyman can discard the unprofitable animals, and gradually build 

 up a herd of high producers at small expense by using a bred-for-pro- 

 duction sire and keeping all heifer calves from the best cows. By this 

 means the average yield of fat for the herd can be gradually increased 

 year by year, until it is raised to 250 Ibs., later to 300 Ibs., and then even 

 higher. As good cows sometimes have "off years" in production, ani- 

 mals should not be discarded after a single year's trial if there is good 

 reason to believe they will do better in the future. 



546. Keeping records of production.- The most satisfactory way to find 

 out the value of each cow is to weigh and record each milking from every 

 animal. This does not require much work, if a convenient spring balance 

 and handy milk sheets for entry of the records are provided. Such 

 daily individual records make possible the feeding of each cow with the 

 greatest economy, enable the herdsman to detect sickness quickly by 

 the decline in milk flow, and aid in judging the efficiency of the differ- 

 ent milkers. Where the weight of each milking is recorded, it is suffi- 

 cient to take a sample covering 3 to 5 days of each month for the butter- 

 fat determination. 



Those who feel that they cannot spend the time necessary to weigh 

 each milking may obtain reasonably satisfactory records by weighing 

 and sampling the milk of each cow regularly on 3 consecutive days each 

 month thruout the year. The average yield of milk and fat for this 

 period is taken as the average for the month. Another method of less 

 value, but better than no testing, is to record the production of each cow 

 for 7 consecutive days at intervals of 3 months. 



Tests covering only a week or even a month of the year are far less re- 

 liable than yearly tests, for cows differ widely in persistence of milk 

 yield. A cow which gives a good flow of milk for a time but goes dry 

 relatively soon may be much less profitable than a persistent milker that 

 never yields as much fat in any one week as does the first cow. 



For example, Glover 9 reports that during 3 years the best weekly 

 record of one cow in an Illinois dairyman's herd was 309 Ibs. of milk 

 and 10.5 Ibs. of fat. In her best lactation period, which lasted 266 days, 

 she produced 5,355 Ibs. of milk and 184 Ibs. of fat. The best weekly 

 record of another cow was 197 Ibs. of milk and 10.2 Ibs. of fat, less than 

 the first cow. During her best lactation period (315 days) this cow, 



"111. Cir. 84. 



