PRINCIPAL SWINE FEEDS AND THEIR USE 139 



Let us bear in mind that too much common salt fed sud- 

 denly may cause trouble. Accustom pigs to it slowly, and do not 

 throw in the troughs any brine in which salt pork has been, be- 

 cause in this case pigs, particularly if they have not been getting 

 meatmeal tankage or similar feeds, will be so anxious because of 

 the meat flavor of the salt brine to consume it that they may con- 

 sume an extraordinary amount, and the salt in it may kill them. 

 Primarily, we think, in these cases, because of the favorable meat 

 flavor of the salt brine, they over-consume. But then, too, salt 

 thrown out to the pigs even in its original form is apt to cause 

 trouble, if they have been starved from it for a long time. 



Sulphur. This may be allowed. We are not sure of the 

 efficiency of sulphur, but believe that powdered sulphur or Glau- 

 ber's salts, which is really a sodium sulphate, can be allowed to 

 pigs to good advantage. Perhaps both can be allowed but we are 

 inclined to favor the Glauber's salts. We hope to have something 

 more definite to offer on this later. These sulphur compounds are 

 supposedly valuable because they furnish sulphur, which is an 

 essential constituent of bodily protoplasm and which must be pres- 

 ent in the ration somewhere, or else an animal cannot grow 

 properly. 



Charcoal or Slack Coal. Just why charcoal, slack coal or 

 partially burned cobs are fed they all being of about the same 

 character is not exactly known. It is usually said that charcoal 

 is fine because it absorbs alimentary gases, but no one has yet dem- 

 onstrated that the gases should necessarily be absorbed in this 

 manner. Anyhow, apparently, they offer some advantages. We 

 believe that if these materials are supplied to pigs, and they eat 

 of them, the chances are that they may do some good. We have 

 found that pigs receiving corn alone are more likely to eat large 

 quantities of charcoal or slack coal than those that have a prop- 

 erly balanced ration, made up of corn and meatmeal tankage, or 

 corn and milk, and we have found that pigs that have been furn- 

 ished with corn and meatmeal tankage free-choice style during the 

 entire period of their lives in drylot eat very little charcoal in their 

 earlier stages of development, when they are on a heavy tankage 

 ration, consuming up to say % to % of a pound daily. But when 

 pigs reach 300 pounds or thereabouts, and are living practically 

 entirely on corn (maybe 1 percent would be meatmeal tankage), 

 then they begin to eat charcoal, eating more in one day than in 

 their whole previous lives, and not only one lot that we have ex- 

 perimented with but many have done this, thus indicating that 

 there is a newly-developed need, after hogs come down to prac- 

 tically entirely corn. 







Some day we may know more about mineral mixtures, but to- 

 day we are in a transition state of knowledge concerning these 

 mixtures, and so long as things are uncertain in regard to them we 

 prefer not to give mixtures, but would emphasize the free-choice 



