digestibility and utilization of protein 

 and energy. These results contradict 

 any advantages claimed for the pur- 

 chase of the higher priced coarse 

 dairy feed for dairy cows. 



N. F. CoLovos, H. A. Keener, 

 A. E. Teeri and H. a. Davis, 



Grass Silage Produces Good Growth 

 When Fed to Dairy Heifers 



In a continuation of the work to 

 determine the best method of pre- 

 serving forage, silage was found to 

 contain the most protein on the dry 

 basis, mow-cured hay was second, 

 while field-cured hay was lowest. 

 The forage used was a gras^-legume 

 mixture containing a high percentage 

 of red clover and it was harvested 

 so that the material stored by all 

 three methods would have had the 

 same original composition. When 

 these forages were fed to 12-18 

 months old dairy heifers as the sole 

 ration, silage produced by far the 

 best gains; field-cured hay was in- 

 termediate, while the mow-cured hay 

 produced the smallest gains. This 

 was in spite of the fact, as reported 

 elsewhere, that the silage was much 

 inferior to both hays with respect to 

 the digestibility of both protein and 

 energy. 



In other experiments with heifers 

 of a similar age, oat silage preserved 

 with sulphur dioxide produced gains 

 in body weight which were just as 

 high as those produced by a similar 

 silage preserved with molasses. The 

 sulphur dioxide preserved silage was 

 also higher in carotene and had much 

 better keeping qualities during warm 

 weather than the molasses treated 

 silage. Better than normal gains in 

 body weight resulted from feeding a 

 ladino-brome silage as the sole ra- 

 tion. When timothy silage was fed 

 as the sole ration, the growth rate 

 was very poor, but it was improved 

 to some extent by feeding corn silage 



along with the timothy silage. Corn 

 silage also increased the growth rate 

 when it was fed along with hay. 



It is concluded that normal 

 body weight gains can be made by 

 dairy heifers after one year of age 

 when they are fed only high quality 

 grass-legume silage alone or in com- 

 bination with corn silage. Good grass 

 silage appears to contain some sort 

 oi: growth-promoting factor (or fact- 

 ors) in much greater quantities than 

 is found in hay. The ensiling of a 

 poor quality forage will not make a 

 high quality feed out of it. Sulphur 

 dioxide appears to have considerable 

 possibilities as a silage preservative. 



H. A. Keener 

 N. F. CoLOvos 

 H. A. Davis 



Limestone Lowers Digestibility 

 Of Silage 



Because of the lower digestibility 

 of silage compared to mow-cured 

 and field-cured hay as determined in 

 experiments elsewhere reported, it 

 was deemed desirable to determine 

 the causes of these differences. It 

 was thought that pulverized lime- 

 stone, a common mixed concentrate 

 ingredient, might be used to neutral- 

 ize the acidity of the silage and per- 

 haps improve its digestibility. Con- 

 trary to this idea, however, the re- 

 verse was found to be true. The feed- 

 ing of ground limestone at a rate of 

 100 g. per day caused a drop of 6 

 to 8 per cent in the digestibility of 

 the protein in the silage. 



The results of this investigation 

 ])ose the very important question as 

 to what harm, if any, inclusion of 

 minerals in the ration in improper 

 proportions may cause in the di- 

 gestion and utilization of its nutr- 

 ent constituents. 



N. F. CoLOVos, H. A. Keener, 

 A. E. Teeri and H. A. Davis 



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