52 



HATCH EXPERIMENT STATION. 



[Jan. 



the period proper of .53 per cent. It is to be noted tliat 

 the nitrogen during this period was .034 per cent, lower 

 than in tlie previous period. A similar decrease was noticed 

 when linseed oil was fed. ^ 



The percentage of solid matter in both herds suffered a 

 slight decline during the third period, possibly due to winter 

 weather conditions ; but it was greater in case of Herd II., 

 due largely to the decrease of the solids not fat. 



In the fourth or corn meal period the milk of Herd I. 

 increased a little in total solids, perhaps due to advanced 

 lactation or to warmer weather. In case of Herd II., the 

 sudden removal of the corn oil caused a temporary decrease 

 of .54 per cent, of fat and a slight increase in the nitrogen. 

 The so-called fat equilibrium, however, was gradually 

 restored ; for in the second week of the preliminary period 

 it was equal to that yielded during the last week of the 

 former period, and the percentage continued quite regular 

 during the entire period. The percentage of nitrogen 

 gradually increased for several weeks, and diu-ing the last 

 week of the period it was equal to the average percentage 

 found during the second period. Similar conditions were 

 observed in former experiments.^ 



Attention is called to the evenness in the composition of 

 the milk produced by Herd I., which had the same feed for 

 a period of six months, the only change worthy of notice 

 being the gradual increase of the solids not ftit from 9.19 to 

 9.58 per cent. 



Table VU. — Composition of the Butter Fat.^ 

 First period : both herds, standard ration. 



1 Thirteenth report of tliis station, pp. 107-109. 2 Xoo. Cit. 



s Methods of the Association of Ollicial Agricultural Chemists. 



