8 N. H. Agr. Experiment Station [Bulletin 291 



The checking of milk cans showed that they were not being sterilized 

 sufficiently at the receiving station. The steam pressure at the station was 

 immediately increased from around 40 pounds to 60 pounds maximum. A 

 drop in the number of can counts followed at once ; the steam pressure was 

 then increased to 80 pounds maximum on January 1, 1932, and to 100 

 pounds maximum pressure April 1, 1932. On June 15, 1933, a new 20 h.p, 

 boiler replaced the old 15 h.p. boiler, and the steam pressure was run con- 

 tinuously at 100 pounds maximum. It was further found that when the can 

 washer was run in fast speed and the steam pressure was low the milk cans 

 were not sterilized enough. Eventually the machine was set in low speed 

 so that it required three minutes for a can to pass through. This longer per- 

 iod of sterilizing combined with twice the amount of steam pressure reduced 

 the number of bacteria found thereafter in milk cans to a negligible amount. 

 In fact, several cans were checked and found to be completely sterile. 



When Pattee station is compared with three other Grade A stations, 

 namely, those at North Haverhill, N. H., Lancaster, N. H., and Shelburne 

 Falls. Mass., the improvement in the quality program made by the producers 

 of this station is most striking. In 1931 the producers of Pattee were in first 

 place only five times compared with 19 times in 1932 out of a possible 24 

 times. The average percentage of Pattee producers under 10.000 bacteria 

 counts during the 24-pay periods was only 54.7 per cent in 1931. In 1932 

 this average percentage had increased to 73.4 per cent. On the other hand, 

 the average percentage of producers with counts under 10,000 at Lancaster, 

 North Haverhill, and Shelburne Falls in 1931 was 62.1 per cent, 56.9 per 

 cent, and 50.4 per cent respectively, and in 1932, it was 62.9 per cent, 58.5 

 per cent, and 63.4 per cent respectively. Pattee producers improved their 

 counts about 19 per cent, Shelburne Falls producers about 13 per cent, and 

 Lancaster and North Haverhill stations remained practically the same. 



During the three-year period the amount of milk on which premiums 

 were paid to the Pattee producers declined from 5.412,877 pounds in 1931, to 

 5,178.157 pounds in 19232, and to 3,683.447 pounds in 1933. (See Table 3.) 

 The average premium rate per cwt. was 34 cents in 1931, 38 cents in 1932, 

 and 37 cents in 1933. The total premiums paid in 1931 represented over 12 

 per cent of the gross milk receipts, in 1932 over 14 per cent, and in 1933 

 over 12 per cent of the gross milk receipts. 



There were about the same number of Grade A shippers during the 

 three years. According to the records, the number ranged from 88 to 100 

 and averaged 94 in 1931, from 93 to 107 with an average of 98 in 1932, and 

 from 88 to 118 with an average of 98 in 1933. On this basis the averaee 

 amount of premium paid producers was $196.58 in 1931, $195.91 in 1932, 

 and $142.07 in 1933. 



Boston Board of Health Scores 



About 31 of the Grade A dairies at Pattee were inspected by the repre- 

 sentative of the Boston Board of Health during 1932. Each dairy was 

 scored by the inspector according to recognized standards so as to insure 

 the qualitv of the milk supply. One dairy was scored at 54.3, three from 

 60 to 70, 19 from 70 to 75, and eight from 75 to 80. The one which scored 

 below 60 was temporarily disquahfied until certain conditions were cor- 

 rected as outlined by the health inspector. These inspections were made 

 during 1932 — the majority of them during the fall months. 



When a scatter diagram (see Figure 2) is made of all the bacteria 



