562 IOWA DEPARTMENT OF AGRICULTURE. 



fine what I have to say to a few suggestions regarding some points in test- 

 ing that have given more or less trouble. 



The first persons that became acquainted with the test were the cream- 

 ery butter makers; they soon learned how to operate it and I think that after 

 using the test a while, every competent butter maker feels as if he is able 

 to test milk accurately, although he connot always give a satisfactory ex- 

 planation for some of the results he gets. His experience soon shows him 

 that the cause for what may seem to be an abnormal test or result must 

 be sought for in the sample instead of being the result of a faulty method 

 of testing. This confidence which the butter maker has in the method is 

 not always shared in by everyone who is interested in the test. It often 

 happens that dairymen or creamery patrons from their lack of familiarity 

 with the subject are sometimes suspicious and inclined to condemn the 

 method whenever the results obtained do not correspond with their Idea 

 of what the tests ought to be. 



It is occasionally hard for a patron to understand why the tests of his 

 cow's milk will vary as is sometimes the case. He naturally thinks that 

 so long as he feeds the same cows the same feed that the tests of their 

 milk ought to be uniform from week to week. This undoubtedly ought 

 to be true and is in many cases, but observations made by testing the milk 

 of each cow in a herd at every milking for a full period of lactation have 

 shown that any kind of excitement, such as hurrying the cows, roughly 

 treating them or exposing them to cold, wet weather will very often have 

 an immediate effect on the milk test. It has also been noticed that indi- 

 gestion will also effect the test of a cow's milk. This was very strikingly 

 illustrated in the dairy tests at the World's Fair. The superintendents 

 of the different herds at that time kept a careful watch of the daily tests 

 of each cow's milk and I well remember that any sudden rise or fall in the 

 tests would direct the herdsman's attention to such cows and a careful 

 examination of them would be made at once. 



There are many other ways of varying the test of milk and we recently 

 had an illustration of a variation in a patron's milk test at the Wisconsin 

 Dairy School that may be of interest to others. A sudden drop was noticed 

 in the test of the weekly composite sample of a certain patron's milk and 

 he at once came to the creamery to see what was the matter. We dis- 

 cussed the subject a while and I tried to suggest all the things I had ever 

 heard of as the possible cause of the drop in test. I did not seem to make 

 much impression on him for he said he "had no new cows and no fresh 

 ones." He was feeding corn and every part of the feeding and milking 

 was being done in the same routine way each day. He knew this to be true 

 because he was doing the work himself. He suggested that either our 

 sampling or our testing was incorrect and that the creamery should pay 

 for his milk on the basis of the tests obtained before the sudden drop. The 

 creamery manager could not find a good reason for accepting this proposi- 

 tion and explained to the patron how the milk samples were taken and how 

 the testing was done at the creamery. This did not convince the patron 

 who insisted that there must have been some mistake at the creamery and 

 that he was the loser on account of another man's error. The manager 



