N. H. Agr. Experiment Station 



[Bulletin 291 



producers were improving their methods, and the volume of Grade A milk 

 was gradually increasing. But the quality of B milk was greatly improved. 

 Consequently there was not much apparent difiference to the consumer be- 

 tween the two classes. Because of these conditions and the lessened demand, 

 the basis of Grade A was cut from 100 per cent of Class I ratings during 

 the period to 85 per cent and still lower to 75 per cent, as shown in Table 1. 



Grade A Standing 



A wide seasonal fluctuation occurred in the percentage of producers who 

 kept their bacteria counts under 10,000. (See Figure 1.) This fluctuation 

 was in direct correlation with the premium rates paid. For illustration, in 

 1931 the highest premium rates were paid in June, July, August, and Sep- 

 tember, when the smallest percentage of the producers was able to keep their 

 counts under 10,000. In 1932 there was a seasonal drop in June, August, 

 and September, but not in July and the first part of August. In 1933 the 

 decline occurs in July, August, and September. Expressed on a percentage 

 basis for June, Jwly, August, and September, only 41.5 per cent had counts 

 averaging 10,000 in 1931, 67.1 per cent in 1932, and 60.9 per cent in 1933. 

 The better showing made in July and August of 1932 was without doubt due 

 to a better understancHng on the part of the producers of the factors causing 

 bacterial growth and of better methods of control. The tendency for the 

 percentage of low counts to taper ofif during the summer months may be 

 partly due to the lessening of the farm ice supply and the practice of drying 

 off cows previous to establishing a base rating during the fall months. 



PERCENT 

 100 



90 .. 

 80 .. 

 70 



60 4- 

 50 



40 4. 

 30 

 20 



10 4. 







\ A.'*\ .A 



i^fc-^ 



■^ • > -• 





'^ ^-^.^ 



CODE 

 a' ^.^^l933,PERCEnT OF PRODUCERS 



«...»...• 1932, ' 



» »» »> 



X — X— vl95l, 



t> •> » 



JAN FEB ri/^R APR mr JUHi Jl/ir AUG SCPT OCT NOV DEC 



Figure 1. Comparison of the per cent of Grade A producers whose counts 



averaged under 10,000 for each pay period during the years 



1931, 1932, and 1933. 



