ILT^TNOIS STATE DAIRYMEN'S ASSOCIATION. 93 



that all cold or all conditions are objectionable or that make 

 an animal uncomfortable will have a tendency to us and waste 

 food energy. So see that she is absolutely comfortable. 



Now, having these three conditions, comes the problera 

 of the amount of fuel to use. Many experiments have been 

 carried on during the past five or six years comparing the 

 different kinds of food stuffs. From my observation, not only 

 during the years that I have been in the Experiment Station, 

 but also during the time that I have been engaged in breeding 

 and dairying, it seems to me that there is very little differ- 

 ence between food stuffs, provided they contain the nutrients 

 needed by the animal. In other words, I find that if I am 

 feeding corn and it is dearer than barley, that I can substitute 

 barley for corn with equally good results. I find that I can 

 eliminate corn from my ration and add ground wheat with 

 equally good results. I can take out wheat and substitute 

 rye with equally good results, if the animal will eat it. Cattle 

 are not as fond of rye as they are of barley and wheat and 

 corn. So we can go on and substitute quite a large list of food 

 stuffs in place of the barley or corn ; they are, in fact, feeding 

 equivalents, containing about the same amount of protein and 

 carbo-hydrates as of corn. This being the case, we can 

 choose whichever one of these feed stuffs is most economical 

 as the principal portion of our ration. Then, in order to 

 produce dairy products economically, we must have the food 

 contain the exact proportion. of the different nutrients that is 

 needed. In order to do that, we will take corn as the stand- 

 ard. We find it contains too much carbo-hydrates and that 

 it is short in protein. Of course we always select from the 

 farm first, so we will add a few pounds of oats; figure up 

 again, find out how much the two contain in carbo-hydrates 

 and in protein and finding the ration is still short of protein 

 or milk-producing ingredients, we try another of our next 

 cheapest feed stuff, with a high per centage of protein, which 

 probably is bran. We will add whatever we think we can 

 afford of bran, and then adding up the totals of the amount 

 of protein and carbo-hydrates, we will very likely find that 

 we are still short in our proportion of these two nutrients, 

 and we may have to add a little oil meal in order to balance 

 it. In this way we can build the ration according to our 



