8 MASS. EXPERIMENT STATION BULLETIN 291 



Table 4. — General Appearance of Cows. 



Age at Appearance 



Conclusion At the beginning At the end or 



OF Experiment or when included in when withdrawn from 



Cow No. Years Months the experiment the experiment 



High Roughage Group 



35 10 7 Good Excellent 



71 8 3 Good Good 



88 7 2 Excellent Excellent 



98 4 . . (a) Fair Good 



128 3 11(6) Fair Good 



137 3 7(c) Fair Good 



139 4 8 Good Fair 



143 3 3(d) Good Fair 



144 4 4 Excellent Good 



Low Roughage Group 



15 11 6(c) Good Good 



33 10 6 Good Good 



40 6 1 1 CO Fair Fair 



99 5 »{g) Fair Good 



121 4 6(h) Good Excellent 



126 S 6 Good Good 



138 4 8 Good Excellent 



141 4 7 Fair Excellent 



(a) Age when sold June 17, 1929. Very poor producer. 



(b) Age when sold September 23, 1930. Aborted and had been a poor producer previously. 



(c) Age when sold February 16, 1931. Reactor to tuberculin test. 



(d) Age when sold February 16, 1931. Reactor to tuberculin test. 



(?) Age whensold February 16, 1931. Old cow getting thin and lame. 

 if) Age when sold July 15. 1929. Could not get her with calf. 

 (g) Agewhensold February 16, 1931. Reactorto tuberculin test. 

 (h) Age w^hen sold February 16,1931. Reactorto tuberculin test. 



Body Weight 



Because two-thirds of the individuals were immature when inckided in the 

 experiment, maintenance of body weight could not be used as a criterion. It has 

 been necessary to compare instead the relative gain in weight of the two groups, 

 care being used to have weights for any one individual at beginning and end repre- 

 sent approximately the same stage of gestation. The weights are shown in Table 5. 



With one exception' all the individuals gained in weight during the course of 

 the experiment, the older cows making moderate gains, while the younger ones 

 made normal to excellent growth. Taking the data in Table 5 at their face value it 

 would seem that the low roughage ration was somewhat superior to the high rough- 

 age ration for maintenance and growth. It must be pointed out, however, that 

 the average time interval between the two series of weights was twenty-seven 

 months in this group while the average time inter\'al for the high roughage group 

 was twenty-two months. Assuming that had the time interval for the latter group 

 also been twenty-seven months they would have continued to gain in weight at a 

 rate equal to the average for the twenty-two month interval, the average individ- 

 ual gain would then have been 124 pounds and the percentage gain for the group 

 11.5 per cent. The above assumption may not be strictly justifiable, but no 

 better means of adjustment is known and in fairness some allowance should be 



^This cow was purchased for the experiment and at time of purchase was in show condition, carrying 

 considerably more flesh than it is our practice to have our animals carry. Her failure to gain in 

 weight is attributed to this reason. She was by no means thin when the experiment was completed. 



