TWO SYSTEMS OF FEEDING DAIRY COWS . 5 



The rations fed to both groups were of the same general character, the differ- 

 ence between the groups consisting in the proportion of roughage to concentrates. 

 The high roughage group received grain at the average rate of one pound to 4| 

 pounds of milk, approximately thirty-five pounds of corn silage (November 

 through April) and as much hay as they would clean up. The low roughage group 

 received grain at the average rate of one pound to 2^ pounds of milk, approximately 

 twenty pounds of corn silage (November through April) and as much hay as they 

 would clean up. The amounts of grain were adjusted each month according to 

 the milk yield. The rations in general were adjusted according to Haecker's stan- 

 dard whenever a change was made in the kind of roughage, e. g., from silage to 

 rowen, or from rowen to green feed. Dry cows received 50 per cent in excess of the 

 nutrients required for maintenance. The average amounts of grain and roughage 

 for each group over the entire period appear in Table 1. When silage was not 

 available, rowen and first crop hay were fed in equal or approximately equal 

 amounts except during July, August, and September, when the rowen was re- 

 placed by such green crops as oats and peas, millet, and fodder corn^, five pounds 

 of green feed being substituted for one pound of rowen. The hay was a mixed 

 hay of good quality grown on the station grounds, containing at times considerable 

 clover, but composed for the most part of timothy, red top, June grass, and sweet 

 vernal grass. At any given time all feeds for both groups were from the same 

 original lots. In order to keep the protein level for both groups approximately the 

 same, it was necessary to feed to the high roughage group a grain mixture some- 

 what richer in protein than that fed to the low roughage group. This was done by 

 varying the proportions of the several ingredients in the two mixtures. The formu- 

 las of the mixtures appear below. 



Grain Mixture 

 For high roughage For low roughage 

 group group 



Per cent Per cent 



Wheat bran 20 20 



Ground oats LS 25 



Corn meal 15 30 



Gluten feed 25 • 15 



Cottonseed meal 25 10 



These mi.xtures contained respectively about 17.9 and 12.8 per cent of digestible 

 protein. The average composition of all feeds used in the e.xperiment is shown in 

 Table 2. Table 3 shows the total and average amounts of dry matter, digestible 

 protein, and total digestible nutrients consumed in each group. 



A study of Table 1 shows that while the average daily amount of feed recom- 

 mended for the high roughage group was slightly in e.xcess of that recommended 

 for the low roughage group (.6 pound more), the amount fed was .5 pound less and 

 the actual amount eaten was .7 pound less. This seeming discrepancy was due 

 to the fact that considerable trouble was experienced from time to time in getting 

 the cows in the high roughage group to eat sufficient roughage to meet their theo- 

 retical requirements according to Kellner's standard. A persistent effort was made 

 to overcome this difficulty by offering the cows their theoretical quota of roughage 

 for days at a time, even when it was evident that they were wasting considerable 

 quantities of it, in the hope that in time they would become accustomed to the 



It would have been desirable to have had pasture for the cows during the summer, but as none was 

 available within reasonable distance green feed was resorted to. It is not believed that under pres- 

 ent farming conditions a system of green crops is economical for the average farmer. 



