16 BULLETIN 501, U. S. DEPARTMENT OF AGRICULTURE. 
These values are figured on the basis of a ton of manure being 
worth $1 at the barn and on a production of approximately 1| tons 
per cow per month during the period they are kept in the stable. 
From the data en three of these farms, showing the quantity of 
manure actually hauled to the fields, it is evident that the credit 
given for manure is liberal. It is easy to overestimate the actual 
credit value of manure per cow, and before deciding on a definite 
valuation for any herd it may be well to consider the care taken of 
the manure and the quantity that is actually returned to the land 
where crops can use it. 
VALUE OF CALF. 
The value of calves at birth depends upon their breeding and sex. 
Heifer calves from high-producing grade cows are usually valued 
higher than males. In regions where the main product of the dairy 
is market milk the common practice is to raise but few of the heifer 
calves. All the bull calves and most of the heifer calves are dis- 
posed of shortly after birth. On the Pennsylvania farm the number 
of heifers selected for raising was relatively small as compared with 
the numbers sold or killed at birth, so that the credits for calf values 
in this herd is low, amounting to but SI. 16 per cow. Calf credits 
on the other three farms are 84.16. $4.52, and $4.74 per cow. 
MINOR CREDITS. 
Certain minor credits are shown on these farms as receipts for sale 
of hides, fees for bull services, fair premiums, and rebates for feed 
sacks. 
APPRECIATION" CREDIT. 
In some herds for certain years, or for a period of years, there 
may be a credit for appreciation. This may be the result of careful 
management in building up a higher producing herd by using a pure- 
bred sire and the introduction of pure-bred cows. This method of 
management accounts for the appreciation of 86.37 per cow on the 
Wisconsin farm. Adding this appreciation credit to the 815.38, as 
given in Table IX. the percentage of costs other than feed offset 
by credits on this farm is increased from 29.3 to 41.2 per cent. On 
the Xorth Carolina farm there is an appreciation for one year, which 
is more than offset by the depreciation of other years, and the result 
is an average net depreciation of 83.52 per cow, as shown in Table I. 
The question of depreciation is discussed farther on (see p. 26.) 
QUANTITY OF MILK PRODUCED. 
Table X gives the average quantity of milk produced per cow on 
the four farms for each year production records are available. On 
three of these farms the yearly average is little over 5,000 pounds 
