In any attempt to estimate the average value of the manure derived from
the consumption of food for the production of milk, the difficulty
arising from the very wide variation in the amount of milk yielded by
different cows, or by the same cow at different periods of her
lactation, is increased by the inadequate character of information
concerning the difference in the amount of the food actually consumed by
the animal coincidently with the production of such different amounts of
milk. But although information is lacking for correlating, with
numerical accuracy, the great difference in milk-yield of individual
cows with the coincident differences in consumption to produce it, it
may be considered as satisfactorily established that more food is
consumed by a herd of cows to produce a fair yield of milk, of say 10 or
12 quarts per head per day, than by an equal live-weight of oxen fed to
produce fattening increase. In the cases supposed it may, for practical
purposes, be assumed that the cows would consume about one-fourth more
food than the oxen. Accordingly, in the Rothamsted estimates of the
value of the manure obtained on the consumption of food for the
production of milk, it is assumed that one-fourth more will be consumed
by 1000 lb. live-weight of cows than by the same weight of oxen; but the
estimates of the amounts of the constituents of the food removed in the
milk, or remaining for manure, are nevertheless reckoned per ton of each
kind of food consumed, as in the case of those relating to feeding for
the production of fattening increase. It may be added that the
calculations of the amounts of the constituents in the milk are based on
the same average composition of milk as is adopted in the construction
of Table V. Thus the nitrogen is taken at 0.579 (= 3.65 nitrogenous
substance)%, the phosphoric acid at 0.2175%, and the potash at 0.1875%
in the milk.
Table VIII. shows in detail the estimate of the amount of nitrogen in
one ton of each food, and in the milk produced from its consumption, on
the assumption of an average yield of 10 quarts per head per day; also
the amount remaining for manure, the amount of ammonia corresponding to
the nitrogen, and the value of the ammonia at 4d. per lb. Similar
particulars are also given in relation to the phosphoric acid and the
potash consumed in the food, removed in the milk, and remaining for
manure, &c. This table will serve as a sufficient illustration of the
mode of estimating the _total or original_ value of the manure, derived
from the consumption of the different foods for the production of milk
in the case supposed; that is, assuming an average yield of a herd of 10
quarts per head per day.
In Table IX. are given the results of similar detailed calculations of
the _total or original_ manure-value (as in Table VIII. for 10 quarts),
on the alternative assumptions of a yield of 6, 8, 12 or 14 quarts per
head per day. For comparison there is also given, in the first column,
the estimate of the _total or original_ manure-value when the foods are
consumed for the production of fattening increase.
So much for the plan and results of the estimations of _total or
original_ manure-value of the different foods, that is, deducting only
the constituents removed in the milk, and reckoning the remainder at the
prices at which they can be purchased in artificial manures. With a view
to direct application to practice, however, it is necessary to estimate
the _unexhausted manure-value_ of the different foods, or what may be
called their _compensation-value_, after they have been used for a
series of years by the outgoing tenant and he has realized a certain
portion of the manure-value in his increased crops. In the calculations
for this purpose the rule is to deduct one-half of the _original
manure-value_ of the food used the last year, and one-third of the
remainder each year to the eighth, in the case of all the more
concentrated foods and of the roots--in fact, of all the foods in the
list excepting the hays and the straws. For these, which contain larger
amounts of indigestible matter, and the constituents of which will be
more slowly available to crops, two-thirds of the _original
manure-value_ is deducted for the last year, and only one-fifth from
year to year to the eighth year back. The results of the estimates of
_compensation-value_ so made are given for the five yields of 6, 8, 10,
12 and 14 quarts of milk per head per day respectively in Lawes and
Gilbert's paper[6] on the valuation of the manures obtained by the
consumption of foods for the production of milk, which may be consulted
for fuller details. It must, however, be borne in mind that when cows
are fed in sheds or yards the manure is generally liable to greater
losses than is the case with fattening oxen. The manure of the cow
contains much more water in proportion to solid matter than that of the
ox. Water will, besides, frequently be used for washing, and it may be
that a good deal of the manure is washed into drains and lost. In the
event, therefore, of a claim for compensation, the management and
disposal of the manure requires the attention of the valuer. Indeed, the
varying circumstances that will arise in practice must be carefully
considered. Bearing these in mind, the estimates may be accepted as at
any rate the best approximation to the truth that existing knowledge
provides; and they should be found sufficient for the requirements of
practical use. Obviously they will be more directly applicable in the
case of cows feeding entirely on the foods enumerated in the list, and
not depending largely on grass; but, even when the animals are partially
grass-fed, the value of the manure derived from the additional dry food
or roots may be estimated according to the scale given.
TABLE VIII.--_Estimates of the Total or Original Manure-Value of
Cattle Foods after Consumption by Cows for the Production of Milk.
Valuation on the assumption of an average production by a herd of 10
quarts of milk per head per day._
+----+---------+---------------------------------------+-----------------------------+--------------------------+---------+
| | | Nitrogen. | Phosphoric Acid. | Potash. | |
| | +-------+------+------------------------+-------+------+--------------+------+-----+-------------+Total or |
| | | | | In Manure. | | | In Manure. | | | In Manure. |Original |
| | Descrip-| | In +------------------------+ | In +-------+------+ | In +-------+-----+ Manure- |
|Nos.| tion of | In | Milk | | Nitro-| Value | In | Milk | | Value| In | Milk| |Value| Value |
| | Food. | 1 Ton | from | Total | gen | of Am- | 1 Ton | from | Total | at | 1 Ton| from| Total | at | per Ton |
| | | of |1 Ton |remain-| equal | monia | of |1 Ton |remain-| 2 d. | of |1 Ton|remain-|1-1/2| of Food |
| | | Food.| of |ing for| Am- | at 4 d.| Food. | of |ing for| per | Food.| of |ing for| d. |consumed.|
| | | | Food.|Manure.| monia.| per | | Food.|Manure.| lb. | |Food.|Manure.| per | |
| | | | | | | lb. | | | | | | | | lb. | |
+----+---------+-------+------+-------+-------+--------+-------+------+-------+------+------+-----+-------+-----+---------+
| | | lb. | lb. | lb. | lb. |L s. d.| lb. | lb. | lb. | s. d.| lb. | lb. | lb. |s. d.| L s. d.|
| 1 |Linseed | 80.64 |25.04 | 55.60 | 67.52 |1 2 6 | 34.50 | 9.34 | 25.16 | 4 2 |30.69 | 8.02| 22.67 | 2 10| 1 9 6 |
| 2 |Linseed | | | | | | | | | | | | | | |
| | cake |106.40 |20.86 | 85.54 |103.87 |1 14 7 | 44.80 | 7.79 | 37.01 | 6 2 |31.36 | 6.71| 24.65 | 3 1| 2 3 10 |
| 3 |Decort- | | | | | | | | | | | | | | |
| | icated | | | | | | | | | | | | | | |
| | cotton | | | | | | | | | | | | | | |
| | cake |147.84 |19.27 |128.57 |156.13 |2 12 1 | 69.44 | 7.18 | 62.26 |10 5 |44.80 | 6.22| 38.58 | 4 10| 3 7 4 |
| 4 |Palm-nut | | | | | | | | | | | | | | |
| | cake | 56.00 |17.86 | 38.14 | 46.31 |0 15 5 | 26.88 | 6.68 | 20.20 | 3 4 |11.20 | 5.73| 5.47 | 0 8| 0 19 5 |
| 5 |Undecor- | | | | | | | | | | | | | | |
| | ticated | | | | | | | | | | | | | | |
| | cotton | | | | | | | | | | | | | | |
| | cake | 84.00 |15.66 | 68.34 | 82.99 |1 7 8 | 44.80 | 5.85 | 38.95 | 6 6 |44.80 | 5.07| 39.73 | 5 0| 1 19 2 |
| 6 |Cocoa- | | | | | | | | | | | | | | |
| | nut cake| 76.16 |15.66 | 60.50 | 73.47 |1 4 6 | 31.36 | 5.85 | 25.51 | 4 3 |44.80 | 5.07| 39.73 | 5 0| 1 13 9 |
| 7 |Rape | | | | | | | | | | | | | | |
| | cake |109.76 |12.50 | 97.26 |118.11 |1 19 4 | 56.00 | 4.69 | 51.31 | 8 7 |33.60 | 4.09| 29.51 | 3 8| 2 11 7 |
| | +-------+------+-------+-------+--------+-------+------+-------+------+------+-----+-------+-----+---------+
| 8 |Peas | 80.64 |17.86 | 62.78 | 76.24 |1 5 5 | 19.04 | 6.68 | 12.36 | 2 1 |21.50 | 5.73| 15.77 | 2 0| 1 9 6 |
| 9 |Beans | 89.60 |17.86 | 71.74 | 87.12 |1 9 0 | 24.64 | 6.68 | 17.96 | 3 0 |29.12 | 5.73| 23.39 | 2 11| 1 14 11 |
| 10 |Lentils | 94.08 |17.86 | 76.22 | 92.56 |1 10 10 | 16.80 | 6.68 | 10.12 | 1 8 |15.68 | 5.73| 9.95 | 1 3| 1 13 9 |
| 11 |Tares | | | | | | | | | | | | | | |
| | (seed) | 94.08 |17.86 | 76.22 | 92.56 |1 10 10 | 17.92 | 6.68 | 11.24 | 1 10 |17.92 | 5.73| 12.19 | 1 6| 1 14 2 |
| 12 |Maize | 38.08 |17.38 | 20.70 | 25.14 |0 8 5 | 13.44 | 6.50 | 6.94 | 1 2 | 8.29 | 5.56| 2.73 | 0 4| 0 9 11 |
| 13 |Wheat | 40.32 |17.38 | 22.94 | 27.86 |0 9 3 | 19.04 | 6.50 | 12.54 | 2 1 |11.87 | 5.56| 6.31 | 0 9| 0 12 1 |
| 14 |Malt | 38.08 |17.86 | 20.22 | 24.55 |0 8 2 | 17.92 | 6.68 | 11.24 | 1 10 |11.20 | 5.73| 5.47 | 0 8| 0 10 8 |
| 15 |Barley | 36.96 |17.38 | 19.58 | 23.78 |0 7 11 | 16.80 | 6.50 | 10.30 | 1 9 |12.32 | 5.56| 6.76 | 0 10| 0 10 6 |
| 16 |Oats | 44.80 |16.68 | 28.12 | 34.15 |0 11 5 | 13.44 | 6.24 | 7.20 | 1 2 |11.20 | 5.40| 5.80 | 0 9| 0 13 4 |
| 17 |Rice meal| 42.56 |16.68 | 25.88 | 31.43 |0 10 6 |(13.44)| 6.24 | 7.20 | 1 2 |(8.29)| 5.40| 2.89 | 0 4| 0 12 0 |
| 18 |Locust | | | | | | | | | | | | | | |
| | beans | 26.88 |13.90 | 12.98 | 15.76 |0 5 3 | .. | 5.19 | .. | .. | .. | 4.42| .. | .. | .. |
| | +-------+------+-------+-------+--------+-------+------+-------+------+------+-----+-------+-----+---------+
| 19 |Malt | | | | | | | | | | | | | | |
| | coombs | 87.36 |15.66 | 71.70 | 87.07 |1 9 0 | 44.80 | 5.85 | 38.95 | 6 6 |44.80 | 5.07| 39.73 | 5 0| 2 0 6 |
| 20 |Fine | | | | | | | | | | | | | | |
| | pollard | 54.88 |16.68 | 38.20 | 46.39 |0 15 6 | 64.96 | 6.24 | 58.72 | 9 9 |32.70 | 5.40| 27.30 | 3 5| 1 8 8 |
| 21 |Coarse | | | | | | | | | | | | | | |
| | pollard | 56.00 |15.66 | 40.34 | 48.99 |0 16 4 | 78.40 | 5.85 | 72.55 |12 1 |33.60 | 5.07| 28.53 | 3 7| 1 12 0 |
| 22 |Bran | 56.00 |13.90 | 42.10 | 51.12 |0 17 0 | 80.64 | 5.19 | 75.45 |12 7 |32.48 | 4.42| 28.06 | 3 6| 1 13 1 |
| | +-------+------+-------+-------+--------+-------+------+-------+------+------+-----+-------+-----+---------+
| 23 |Clover | | | | | | | | | | | | | | |
| | hay | 53.76 | 8.94 | 44.82 | 54.43 |0 18 2 | 12.77 | 3.35 | 9.42 | 1 7 |33.60 | 2.94| 30.66 | 3 10| 1 3 7 |
| 24 |Meadow | | | | | | | | | | | | | | |
| | hay | 33.60 | 8.36 | 25.24 | 30.65 |0 10 3 | 8.96 | 3.10 | 5.86 | 1 0 |35.84 | 2.62| 33.22 | 4 2| 0 15 5 |
| | +-------+------+-------+-------+--------+-------+------+-------+------+------+-----+-------+-----+---------+
| 25 |Pea straw| 22.40 | 7.83 | 14.57 | 17.69 |0 5 11 | 7.84 | 2.91 | 4.93 | 0 10 |22.40 | 2.46| 19.94 | 2 6| 0 9 3 |
| 26 |Oat straw| 11.20 | 6.95 | 4.25 | 5.16 |0 1 9 | 5.38 | 2.60 | 2.78 | 0 6 |22.40 | 2.29| 20.11 | 2 6| 0 4 9 |
| 27 |Wheat | | | | | | | | | | | | | | |
| | straw | 10.08 | 5.98 | 4.10 | 4.98 |0 1 8 | 5.38 | 2.23 | 3.15 | 0 6 |17.92 | 1.96| 15.96 | 2 0| 0 4 2 |
| 28 |Barley | | | | | | | | | | | | | | |
| | straw | 8.96 | 5.46 | 3.50 | 4.25 |0 1 5 | 4.03 | 2.04 | 1.99 | 0 4 |22.40 | 1.80| 20.60 | 2 7| 0 4 4 |
| 29 |Bean | | | | | | | | | | | | | | |
| | straw | 20.16 | 5.68 | 14.48 | 17.58 |0 5 10 | 6.72 | 2.14 | 4.58 | 0 9 |22.40 | 1.80| 20.60 | 2 7| 0 9 2 |
| | +-------+------+-------+-------+--------+-------+------+-------+------+------+-----+-------+-----+---------+
| 30 |Potatoes | 5.60 | 2.07 | 3.53 | 4.29 |0 1 5 | 3.36 | 0.78 | 2.58 | 0 5 |12.32 | 0.66| 11.66 | 1 5| 0 3 3 |
| 31 |Carrots | 4.48 | 1.46 | 3.02 | 3.67 |0 1 3 | 2.02 | 0.54 | 1.48 | 0 3 | 6.27 | 0.49| 5.78 | 0 9| 0 2 3 |
| 32 |Parsnips | 4.93 | 1.67 | 3.26 | 3.96 |0 1 4 | 4.26 | 0.63 | 3.63 | 0 7 | 8.06 | 0.49| 7.57 | 0 11| 0 2 10 |
| 33 |Mangel | | | | | | | | | | | | | | |
| | wurzels | 4.93 | 1.32 | 3.61 | 4.38 |0 1 6 | 1.57 | 0.49 | 1.08 | 0 2 | 8.96 | 0.49| 8.47 | 1 1| 0 2 9 |
| 34 |Swedish | | | | | | | | | | | | | | |
| | turnips | 5.60 | 1.14 | 4.46 | 5.42 |0 1 10 | 1.34 | 0.44 | 0.90 | 0 2 | 4.93 | 0.33| 4.60 | 0 7| 0 2 7 |
| 35 |Yellow | | | | | | | | | | | | | | |
| | turnips | 4.48 | 0.93 | 3.55 | 4.31 |0 1 5 | (1.34)| 0.34 | 1.00 | 0 2 |(4.93)| 0.33| (4.60)| 0 7| 0 2 2 |
| 36 |White | | | | | | | | | | | | | | |
| | turnips | 4.03 | 0.84 | 3.19 | 3.87 |0 1 3 | 1.12 | 0.31 | 0.81 | 0 2 | 6.72 | 0.33| 6.39 | 0 10| 0 2 3 |
+----+---------+-------+------+-------+-------+--------+-------+------+-------+------+------+-----+-------+-----+---------+