THE COW IN CALF 



DESERVES MORE HONOR 



Register of Merit of American Jersey Cattle Club Reveals Discrimination 

 Against Cow Carrying Calf During Test Period — Young 

 Cows Now Given the Advantage 



J.J. 1 Ii)()1'i:k 



Kentucky Agrkiiltural Experiment Station 



IT is recognized that breeders of dairy 

 cattle have attained remarkable re- 

 sults in the past decade in increas- 

 ing the productivity of cows. The 

 standard that has been adopted by 

 breeders of Jersey cattle for Register 

 of Merit cows stipulates that they shall 

 prodiice at least 250 pounds of fat 

 when two years old (or younger) and 

 one-tenth of a pound more of fat for 

 each day that they are older, until they 

 reach five years of age when the maxi- 

 mum requirement of .'3(50 pounds of fat 

 has been attained. This applies to tests 

 covering a year. Xo requirement is 

 prescribed for the quantity of milk. It 

 is quite obvious that the standard should 

 be correct and that it should be equally 

 proportioned for all ages. It is hardly 

 fair to place a greater burden on young 

 cows than on old ones, or vice versa. 



In this study we have tabulated rec- 

 ords of 1,497 Register of Merit cows 

 entered in the volume that was pub- 

 lished in 1910. We have kept the rec- 

 ords of the A class of cows separate 

 from those of the AA cows. The A 

 cows are not required to carry a calf 

 during the period of their record, while 

 it is stipulated that the AA cows shall 

 carry their calves at least 155 days cov- 

 ered by their test. It is believed that 

 the AA cows are handicapped by carry- 

 ing a calf in titer o while making a test 

 and accordingly they are given higher 

 rating by being designated as AA cows. 



By reference to the table (See Appen- 

 dix) it will be found that the A cows 

 averaged a little higher in milk and fat 

 production than the AA cows. It 



2.S0 



seems that they have a little ad- 

 vantage in that they are only perform- 

 ing one function, that is, milk produc- 

 tion while the others are performing: 

 two functions, namely, milk produc- 

 tion and also the growth of a calf in 

 utero. At the same time there is not 

 very much ditTerence in their records, 

 as will be observed by referring to the 

 table or to the graph. There it is shown 

 that for the one- and two-year-old cows- 

 there is very little difference between 

 the two classes, but they separate more 

 widely from four to eight years of age. 

 In other words, it seems that a very 

 young cow, with her wonderful vitality,, 

 can perform the two functions easily, 

 but at the age of four years she is taxed' 

 heavily to carry a calf, in comparison 

 with an A cow. When the cows reach 

 the age of eight to ten years they seen> 

 to again possess the ability to carry a 

 calf, without serious detriment to their 

 milk and fat production, in comparison 

 with the A cows. From this study it ap- 

 pears correct that the cows that carry 

 calves for five months or more of the 

 test period deserve some recognition 

 above the other cows, and especially is 

 this true between the ages of four to- 

 eight years. 



Another interesting p<^int brought out 

 in this study is the fact that the A cows- 

 increase in fat and milk production 

 steadily until they reach the age of four 

 years, when they seem to attain almost 

 their maxinuun production, while the 

 AA cows continue to rise in production 

 until they are five years old, apparently 

 maturing a year later than the A cows. 



