530 Bulletin 169. 



largest yield of milk for one year was 13,446.75 pounds which 

 contained an average of 3.19 per cent fat and a total of 428.75 

 pounds of fat. The smallest production of fat was in the year 

 1893-94 and was 121.78 pounds. This was from 3,619 pounds 

 of milk containing an average of 3.37 per cent fat. The smallest 

 yield of milk was 2,203 pounds in the year 1891-92. This con- 

 tained an average of 5.91 per cent fat and a total of 130.13 

 pounds of fat. The annual average yield of milk varied from 

 6,875 pounds in 1892-93 to 7,575 pounds in 1897-98. The aver- 

 age production of fat varied from 265.88 pounds in 1895-96 to 

 291.92 pounds in 1893-94. I'tie lowest average per cent of fat 

 (3.57) was also in 1895-96, while the highest average (3.94) was 

 in 1891-92. The average of all the cows for the seven years was 

 7,331.6 pounds of milk, 275.69 pounds of fat and 3.76 percent fat. 

 The average age for each year ranges from 4 years in 1891-92 to 4.8 

 in 1894-95. The average age for seven years is 4.4 years. It 

 should be noticed that the lowest record for each year was by 

 either a two or three year old, while the highest record was in 

 each case by a full aged cow. 



Production as Influenced by Age. 



With a view to determine the average gain in production as a 

 cow increases in age, we have taken from the records that go to 

 make up Table I, such records as there are beginning with two- 

 year olds and continuing for two or more years. In order to 

 make this comparison as just as possible, the first forty weeks in 

 each period of lactation are taken to represent the cows produc- 

 tion for that period. In only a comparatively few cases do the 

 periods taken in this comparison fall short of forty weeks and 

 these instances are noted in the table. While the shorter periods 

 may work to the slight disadvantage of the cow concerned, still 

 they do not materially affect the average of the whole, which is 

 the most important part of the comparison. The milk records of 

 Bertha, Gem Valentine, Pearl and Ruby as two-year olds were 

 made during the year 1890-91 when the milk was not tested for fat 

 and thus the amount of fat produced cannot be given. This 

 comparison is shown in the following table (III) and along with 

 the forty week records, is given the per cent of gain in milk and 

 fat from one year to another. 



