PROCEEDINGS CORN BELT MEAT PRODUCERS' ASSN. 517 



salt, equal parts; equal parts of limestone, salt and spent bone-black; 

 the fairly complete mineral mixture fed to the gilts; another made up of 

 34.36 pounds of salt, 28.64 pounds of spent bone-black, 13.75 pounds of 

 wood ashes, 11.46 pounds of sulphur, 11.46 pounds of limestone, .34 of a 

 pound of potassium iodide, total 100 pounds; and another, consisting of 

 38.81 pounds of salt, 32.34 pounds of spent bone-black, 15.52 pounds of 

 wood ashes, 12.94 pounds of limestone, .39 of a pound of potassium iodide, 

 total, 100 pounds. 



In this test, twelve lots were fed, ten of which were getting minerals. 

 All of the lots receiving minerals made a slightly greater gain than the 

 average of the two check lots. All of them but one made this gain at less 

 feed required per 100 pounds of gain than the check lots. The lot that 

 made the greatest gain and the cheapest gain was the lot that received 

 limestone and salt in equal parts, hand-fed, at the rate of one-third of an 

 ounce per pig per day. Where we self-fed these different mineral mix- 

 tures, the pigs did not gain quite so much as where it was hand-fed. In 

 the lots receiving mineral mixtures self-fed, the pigs ate about two-thirds 

 as much as where they were hand-fed. 



We ran still another test in dry lot. In this test we fed lots of ten pigs 

 each on a basal ration of shelled corn (self-fed) plus a supplemental mix- 

 ture (self-fed) made up of 40 parts of blood meal, 30 parts of corn oil cake 

 meal, 20 parts of linseed oil meal and 10 parts of peanut meal. This mix- 

 ture was chosen for one likely to provide all the practical essentials of a 

 ration except mineral substances. Eight of these lots received different 

 mineral mixtures. Lot 1 and Lot 10 were check lots and received no min- 

 erals. For Lot 2 we mixed salt with this supplemental mixture so that 

 with every 100 pounds of supplemental mixture the pigs would have to eat 

 three pounds of salt. To Lot 3 we added a mixture of salt and limestone 

 (equal parts), so that they would still have to eat three pounds of salt to 

 every 100 pounds of supplemental mixture, plus three pounds of lime- 

 stone. To Lot 4 we added a mixture of equal parts of salt and bone meal 

 (finely ground bone meal). The next lot received a mineral mixture of 

 equal parts of salt, limestone and bone meal, so that they would be fed 

 nine pounds of this mixture — three pounds of salt, plus three pounds of 

 limestone and three pounds of bone meal — to every 100 pounds of supple- 

 mental mixture. 



Lot 6 received ten pounds of the fairly complete mineral mixture, made 

 of up 30 pounds of salt, 25 pounds of raw bone meal, 12 pounds of wood 

 ashes, 10 pounds of sulphur, 10 pounds of limestone, 5.7 pounds of Glauber's 

 salts, 5 pounds of epsom salts, 2 pounds of copperas and three-tenths of a 

 pound of potassium iodide. 



Lot 7 received the same mineral mixture as Lot 6, except that Glauber's 

 and epsom salts and copperas were left out. 



Lot 8 received the same as Lot 7, except that sulphur was left out. 



Lot 9 received all of the minerals in the fairly complete mineral mixture, 

 self-fed free choice style. 



Six out of the seven groups receiving mineral mixtures made somewhat 

 better gains and showed a little less daily total feed consumption than 

 either of the check lots. 



