FEEDING AND CARE OF DAIRY COWS 251 



curate records may be obtained 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 con- 

 secutive days at intervals of 3 months. Tests covering only a week 

 or even a month of the year are unreliable, 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. 



Cow-testing associations. — The remarkable development of dairy- 

 ing in the Scandinavian countries of northern Europe has been largely 

 due to the work of cow-testing associations. In these organizations a 

 trained tester is employed, who spends a day every month with each 

 of the herds in the association. Arriving on the farm in the after- 

 noon he weighs and samples the milk from each cow at milking time. 

 He furthermore weighs the concentrates given each cow and also the 

 roughage which several get and then estimates the approximate 

 amount given to each cow in the herd. The following morning this 

 is repeated, after which the samples of milk are tested for butter fat. 

 From this day's record he computes the milk and fat production and 

 cost of feed for each cow for the current month. While such records 

 are not as exact as if every milking were weighed, careful studies have 

 shown the results to be within 2 per ct. of the actual production of 

 the cow. The tester also studies the local feed market and aids the 

 dairyman in working out economical rations. Many dairymen who 

 would not test their herds themselves are glad to secure this service 

 at small expense as a member of the association. The improvement 

 wrought by these associations is marvelous. In Denmark, largely due 

 to their work, the average annual yield of butter per cow has increased 

 from 112 lbs. in 1884 to 224 lbs. in 1908. Cow-testing associations are 

 now increasing rapidly in the United States and have already accom- 

 plished much good. The first association in this country was organ- 

 ized in Michigan in 1905. During the first 8 years the average yield 

 of butter fat per cow in 7 herds which had been in the association from 

 the beginning, was increased from 231.1 to 284.7 lbs., and the average 

 net returns over cost of feed were more than doubled. 



Official tests and advanced registry of dairy cows. — The estab- 

 lishment by the dairy breed associations of advanced registers for 

 pure-bred cows is another important development of the dairy indus- 

 try. Cows are entitled to advanced registry only when their yield in 

 tests conducted by representatives of the state experiment stations or 



