14 MASS. EXPERIMENT STATION BULLETIN 291 



DISCUSSION OF RESULTS 



Viewing the results as a whole, the low roughage group of cows had a rather 

 better record. They looked thriftier, put on more flesh, milked more freely, main- 

 tained their production better from year to year, maintained their average test 

 better, and were more nearly normal in their reproductive function. 



In searching for a reason for the better showing of this group the most obvious 

 one is the sightly greater food intake noted on p. 5. This difference in intake of 

 nutrients favors the low roughage group and because of it criticism might be made 

 of the conduct of the experiment. 



It must be pointed out, however, that the discrepancy Is due in some measure at 

 least to an inherent weakness in the high roughage system of feeding which has been 

 brought out by the experiment; viz., that these cows would not, or could not, 

 eat sufficient roughage to satisfy their theoretical requirements when the amount 

 of grain fed was kept down to one pound for each 4^ pounds of milk daily. It 

 is felt also that there must be other reasons for the better showing of the low 

 roughage group. Superiority for milk production of the total digestible nutrients 

 and possibly of the digestible protein in their ration is suggested as another cause. 

 In the high roughage group 24 per cent of the total digestible nutrients and 46 

 per cent of the digestible protein consumed came from the grain, while in the low- 

 roughage group 42 per cent of the total digestible nutrients and 57 per cent of the 

 digestible protein consumed came from the grain. Another factor not to be lost 

 sight of is the additional energy required to digest the extra coarse fodder in the 

 high roughage ration. 



It is evident that cows will not produce to the limit of their ability on a high 

 roughage system of feeding. Whether it is economical to have them do so will de- 

 pend very largely on local conditions as to production and markets, and in a large 

 measure the problem is one for the individual farmer to solve for himself. 



If he is situated relatively far from market, with sufficient low-priced land to 

 grow an abundance of rough feed, and if he has big hearty cows accustomed to con- 

 sume readily large quantities cf hay and ether roughage; then the high roughage 

 system is undoubtedly the one to adopt. If he is near a good market and the demand 

 for milk is such that he is not unduly penalized for surplus production, if he has rela- 

 tively little land and that high priced, and if he has cows of the smaller breeds; 

 then undoubtedly liberal grain feeding is the practice to follow. 



In between these extremes will be found the majority of New England farmers, 

 and it is believed that in a great many cases the ratio of 1 pound of grain to 85 

 pounds of milk is likely to prove the most satisfactory. Each farmer must study his 

 own situation, weigh the facts, and decide for himself. 



In conclusion, it must be emphasized that the high roughage system of feeding 

 cannot prove satisfactory unless the roughage Is of good quality, which means 

 legume or mixed hay cut early and well cured, and corn silage that Is sweet, well 

 eared, and not watery. 



SUMMARY AND CONCLUSIONS 



This bulletin reports the results of an investigation, three and one-half years in 

 length, on the relative merits of two systems of feeding dairy cows. One of these 

 systems involved the feeding of a relatively large amount of roughage and a 

 relatively small amount of grain ; the other Involved the feeding of a relatively small 



