1 Nov., 1897.] QUEENSLAND AGRICULTURAL JOURNAL. 361 
Kiffect of Fatigue on Milk Production. 
Unper the heading “ Agricultural Chemical Notes,” the Scottish Farmer has 
the following article on investigations on the effect of fatigue on the quality 
and quantity of the milk yielded by cows, which were carried out during this 
year by Dr. C. M. Aikman at the Vermont (U.S.) Experiment Station :— 
Seventeen cows were purchased by the station and driven about ten miles, 
transported by rail for fifty miles, and finally driven a mile and a-quarter, 
having thus been on the road ail day. A second lot was purchased and 
transported under exactly similar ‘conditions. The yield and composition of 
the milk was determined on the night of arrival, the following morning, some 
days later, and at the end of two weeks, the following figures being given :— 
Milk Yield. | Total Solids. Fat. (sotias not Fat, 
Lb. Per Cent. Per Cent. Per Cent. 
First Lor— 
Night of arrival — 75 14°95 54h 310) 
Morning after arrival... TA 16°70 7°28 9°42 
Two weeks after arrival ... 88 13°90 - 4°55 9°35 
Seconp Lot— — 
Night of arrival... 88 14°10 5'04 9°06 
Morning after arrival rae ve 11°0 14°98 5°90 9°08 
Two weeks after arrival ... 13 a 12°7 14°14 4°88 9:26 
From these it will be seen that the amount yielded was lessened by fatigue, 
the general quality improved, and a decided increase manifested in the fat. It 
was also noted that half of the cows gave richer, and half essentially the same 
amount of poorer milk on the evening of the day of travel as they gave after 
recovery from fatigue. All gave richer milk the morning following the 
travelling than they did two weeks later. The greatest variation was shown in 
the fat, the solids not fat, remaining almost uniform. 
The effect of heavy exercise on milk production has also been investigated 
by Henkel, who came to the conclusion that moderate exercise exerted a 
favourable influence on the quantity and quality of the milk, while heavy fatigue 
diminished both the quantity and the quality of the milk. The experiments 
were carried out by driving a number of cows a considerable distance, in some 
cases up 2 mountain, and analysing the milk for some days before and after the 
trip. It was found that heavy exercise diminished the yield and also the 
absolute amount of milk constituents. This decrease was more or less notice- 
able in the first milking atter the trip, according to thé severity of the exercise, 
but was more pronounced in the second milking. ‘The amount of water’ 
decreased in the first milking, more in the second milking, and then gradually 
sank to the normal. The percentage of fat was greatly increased in the first 
milking, according to the severity of the exercise; was still greater in the 
second milking, and then gradually sank to the normal. The casein increased 
in the first milking, remained about the same in the second milking, and 
then gradually returned to the normal. The milk-sugar decreased in the first 
milking, and usually rose again to the normal in the second and following 
milkings. The ash constituents were decidedly higher in the first milking after 
the trip, but sank to the normal then. It has been asserted that the acidity 
of milk is greater after exercise, but such was found not to be the case. 
