282 IOWA DEPARTMENT OF AGRICULTURE. 



fed five parts of corn meal to one part of tankage, their gains being 

 larger than those in the Indiana test but somewhat less economical, 

 particularly as to the feed saved by the use of tankage. In the Indiana 

 test, from 33.5 to 38.9 per cent of the corn meal ration was saved by 

 the use of tankage; in the Iowa test from 20.8 to 30.4 per cent was saved. 

 Beef meal fed at the Iowa Station effected a saving of 24.9 per cent 

 in the amount of grain required for 100 pounds of gain. 



THE USE OF DAIRY BY-PRODUCTS. 



The use of dairy by-products in pig feeding makes possible both the 

 most economical returns for the ration and the highest quality in the 

 carcass. 



The injurious effects of feeding a ration of corn meal only can be 

 largely overcome by the addition of skim milk, and comparative tests 

 between rations- of corn meal only and one of corn meal and milk have 

 usually shown advantages for the milk ration out of all proportion to 

 the actual feeding value of the milk. For some time the real cause 

 of this was in doubt, but chemists have quite recently shown that there 

 is a ferment or enzyme in milk which has a digestive action, render- 

 ing from 1 to 3 per cent of the insoluble proteids digestible. Doubtless 

 this ferment is accountable for the high efficiency of a grain and milk 

 ration. 



At the Tennesee Experiment Station pigs on corn meal only made 

 average daily gains of one pound, eating feed at the rate of 416 pounds 

 of dry matter for each 100 pounds of gain made. Pigs on a ration of 

 corn meal and dairy by-products made gains at the rate of 2.3 pounds 

 per day per pig, and the dry substance in the feed eaten was only 293 

 pounds for each 100 pounds of gain, although the pigs ate a great deal 

 more feed than those on corn meal only, the difference being more 

 than made up by the large gains. The net proiit of feeding these 

 pigs for sixty days, value of manure and cost of care and feed being 

 considered, was respectively $7.69 and $12.06 per lot of three pigs. A 

 peculiar feature of this experiment was that the money cost of feed 

 per 100 pounds gain was considerably greater in the cost of the pigs 

 on dairy by-products; this, like the greater consumption of feed, was 

 offset by the increased gain of the pigs on the more expensive feed. If 

 large results are to be obtained, you may often use expensive methods 

 of feeding. Here is w^here one's business judgment must be used. 

 Other results at the Tennessee Station show average daily gains of .50 

 pounds and 1.35 pound for pigs on rations of corn meal only, and corn 

 meal and skim milk, 410 pounds of corn meal in the first case being 

 required for 100 pounds of gain, and 160 pounds of corn meal and 

 1,190 pounds of milk in the second. In this case the money cost ol 

 the skim milk ration was less per one hundred pounds gain, although 

 the total cost was considerably greater than that of the corn meal ration. 

 The results just quoted are the average of two years' investigations. 



The Nebraska Station- has recently published the results of experi- 

 ments in which they show the value of skim milk in a corn meal ration. 

 Pigs on the respective rations of corn meal and corn meal and skim 



