54 STORRS AGRICULTURAL EXPERIMENT STATION. 
is about 9 per cent. of the yield of the preceding month.” The 
shrinkage in butter yield would, of course, be less, because the 
milk grows richer in fat. 
In the case of herd A, instead of a falling off in milk flow there 
was an average daily increase of seven-tenths of a pound in the 
test while they were fed the narrow ration over what it had been 
with the wide ration six weeks earlier. There was practically no 
change in milk flow in the case of the two other herds. With all 
three herds there was a slight increase in butter yield with the 
narrow ration in the second test. ‘The total size of the ration as 
measured by the fuel value averaged less in the second test than 
in the first. ‘The protein was increased and the carbohydrates 
and fats were decreased in the second test. 
In these cases both milk flow and butter yield were so much 
affected by the change from a wide to a narrow ration that 
instead of a shrinkage in production, as would naturally fol- 
low from advancement in. period of lactation, the animals more 
than held their own, Too much importance should not be given 
to a few results, but these are in line with the best observations 
here and elsewhere, that so far as physiological effects are con- 
cerned, narrow (nitrogenous) rations give larger yields of both 
milk and butter than do wide (carbonaceous) rations. 
COST OF MILK PRODUCTION WITH WIDE AND NARROW RATIONS. 
The following tabulations indicate that the cost of milk and 
butter production from the food alone was much less on the nar- 
row ration, even when the cows were six weeks farther advanced 
in lactation than earlier on the wide ration. So far as these tests 
may be taken as an indication, narrow rations may be fed more | 
profitably than wide. 
The cost of food to produce too pounds of milk was as follows: 









TOTAL COST OF FEED. NeET* Cost OF FEED. 
HERD. 
WideeRenent Pees Wide Ration.| “#towen 
Ration. Ration. 
Arie Bogie osree | $1.47 $1.15 $0.79 BO. 52 
B; = - - - 1.00 1.03 53 .50 
SLs - = - 1.41 1:30 gl 73 
Average, > = $1.29 $1.16 $0.74 $0.58 






* Total cost less value of obtainable manure. 


