FEEDING VALUE OF SKIM MIl.K. 109 



is that the milk proved to be worth in money, or pork sold, 3.10 

 cents for each ten pounds or 31 cents a hundred. 



Perhaps the question ma}' now be asked, is buttermilk of equal 

 value with skim milk? Not so many experiments have been made 

 with buttermilk as with skim milk. I have here the results of three 

 experiments involving the use of three pigs in two cases and six in 

 one, and the figures vary greatly ; but the average value of butter- 

 milk is less than skim milk, and that is as it must be, as it seems to 

 me. At the station we have been analyzing buttermilk, taking the 

 buttermilk before the butter is washed, and we find that in a hun- 

 dred pounds of buttermilk there is on the average one pound less of 

 solid matter than in a hundred pounds of skim milk, and I think 

 those figures can be trusted as representing practically the relative 

 amount of solid matter in buttermilk and skim milk. I would ex- 

 press the opinion that these experimental figures do not quite do 

 buttermilk justice, but they are all I could get at. 1 think butter- 

 milk is worth just about a tenth less than skim milk. 



Now what is the skim milk of a cow worth in money for a year? 

 Have you cows that will give 6,000 pounds of milk a year? 



Oiie-fifih of that will go away in cream and you will have left 

 4,8U0 pounds of skim milk worth for pork raising, as a'ou have seen, 

 31 cents a hundred pounds. You are thus getting practically $15 

 out of the skim milk turned into pork, and I will leave it to }ou to 

 say whether the manure from the pig pen will pay for the care or 

 not. Now that in a somewhat brief way finishes that side of the 

 question. 



What about the effect on the fertility of the farm in the loss or 

 use of this skim milk ? Every hundred pounds of skim milk contains 

 about 55-100 of a pound of nitrogen lor which you are paying to-day 

 in commercial fertilizers from 17 to 18 cents a pound. This year 

 you will pay higher for it as compared with last year I expect, 

 because the price has been going up. You have in that hundred 

 pounds of milk about one-fifth of a pound of potash and a little 

 more than a fifth of a pound of phosphoric acid. If you buy those 

 ingredients in commercial fertilizers and pay the ruling prices — and 

 they are worth as much in this milk as there, because they are in an 

 entirely useful form — we will say 18 cents for nitrogen, four cents 

 and a quarter for potash and eight cents a pound for phosphoric 

 acid, the manurial ingredients of your forty-eight hundred pounds of 

 skim milk would cost in commercial fertilizers $5.71. 



