386 STATE BOARD OF AGmcULTTJEE. 



th:at milk produced would be of the bes^t, the milk showed mauurial pol- 

 lution each of the sixteen times that it wais tested. 



We do not cite these caiseis to prove that good surroundings are not de- 

 sirable for the production of clean milk, but as instances, illustrating the 

 often observed fac-t, that a careless dairy man will produce poor milk 

 under the best; of surroundings and that the exceptional dairyman may 

 produce clean milk under the poorest of conditions. We believe, how- 

 ever, and our observations during the contest confirm the belief, that for 

 the average dairyman, the better surroundings the better the milk 

 produced. 



MILK SCORES DURING THE CONTEST. 



The pH sicores of the samples of milk delivered during the contest 

 proper are tabulated as Table II. These represent the condition of the 

 milk as it arrived at the plant during the months of April and part of 

 May. During this time the farmers knew that the contest was in prog- 

 ress, and were receiving weekly letters telling of the contest results and 

 advising them as to methods which might be expected to improve the 

 supply. The average pH score during this period was 78. This is an 

 average improvement of 5 in spite of the fact that the average mean 

 temperature was 22° F. warmer during this period than during the 

 preliminary period. 



The elfect of the temperature upon the average pH score during the 

 preliminary period and during the contest proper is shown in Cliart 

 No. 1. 



DISCUSSION OF CHART NO. 1. 



It will be noted that during the preliminary perio<l a very close rela- 

 tion existed between the atmos]>heri:c temperature and the pH score. 

 Later on in the i)reliminary ])eriod the i)H score improved slightly as com- 

 l)ared with the tem]>erature. This no doubt ^^'alS due to the fact th,at 

 wlien some of the farmers saw samples of their milk taken they became 

 suspicious of something unusual and as a consequence produced the milk 

 with more than the usual care. 



The fact that the line, representing the average pH score of the isamples 

 of milk, checks so well with the temijerature during this period, is a good 

 indicator of the value of this method. A line, rejiresenting the bacterio- 

 logical eount wihen charted in a similar manner, fluctuates from the top 

 of the chart to the bottom showing a very .slight tendency to check with 

 the temperature curve. As the temperature is the only important variable 

 during this period, an efficient method should slioiw a clotse relation to it. 



During the contest ju'oper the curve representing the pH score shows 

 a great iniprovcnient in irelation to the atmospheric temperature curve. 

 As interest in the contest grew the pH score inniiroved even as the tem- 

 perature became warmer. The average pH score during the contest repre- 

 sented an average improvement over the pireliminary i)eriod of 5, although 

 the average mean temperature was 22° F. higher. A comparison of results 

 obtained last year with Chart I indicates that the average pH score 

 this period would have been between 45 and 50 if the contest had uot been 

 during this period would have been between 45 and 50 if the contest had 

 not been in progress. Last year, at a corresponding time, several cans 



