INFLUENCE OF AGE ON THE ECONOMY AND PROFIT 



OF FEEDING CALVES, YEARLINGS AND 



TWO-YEAR-OLDS 



J. H. SKINNER W. A. CocnEi, 1 



During the past three years an experiment has been in progress 

 at Purdue Experiment Station to determine the influence of age on 

 the economy and profit from feeding cattle. Preliminary reports 

 have been made in bulletins Nos. 129, 136 and 142, which contain 

 detailed descriptions of the cattle, methods of feeding, weighing 

 and equipment in use, to which the reader is referred. However, it 

 is well to state in this connection that the calves used in each test 

 were of the best type and breeding that it was possible to obtain, as 

 it is not practical to try to produce prime yearling beef from inferior 

 calves. The yearlings and two-year-olds were selected in such man- 

 ner that they would be comparable with the calves in capacity and 

 condition at the beginning of each test, in order that these two fac- 

 tors should not influence the results. They were not, however, of 

 quite so good type, as illustrated by the initial and final values shown 

 in Tables I and II. At the close of each test the calves were sold 

 at the extreme top price paid for cattle of their weight on the Chi- 

 cago market, while the two-year-olds and yearlings secured this dis- 

 tinction only once in the three trials. In the other two trials they 

 sold from 15 to 20 cents per hundred below the top, due to their 

 being deficient in quality and type, though in each instance they were 

 as fat as the calves when marketed. 



Table I is given in order that a full report of the three trials 

 may be examined. The experiment was repeated in order that condi- 

 tions which could not be brought under entire control might be re- 

 duced to a minimum. This table shows that in each of the three 

 years the calves were valued at a higher price per hundred than the 

 two-year-olds and the two-year-olds higher than the yearlings. The 

 rate of gain varied directly with the age of the cattle in each of the 

 three tests. The amount of feed required to produce a pound of gain, 

 with one exception, the yearlings in 1907-8, increased with the age 

 of the cattle. In each year the time required to make the calves 

 fat was greater than with the older animals. This is on account 

 of the younger animals having to devote a much larger proportion 

 of their feed to growth while the older animals had nearly reached 

 their limit in growth, hence, could devote their feed largely to main- 

 tenance and fat production. 



Associate in Animal Husbandry Resigned December 1, 1909 



