At the same time, it should always be borne in mind that the change from grass to a poor quality of hay or straw, for cows in milk, should not be too sudden. A poor quality of dry hay is far less palatable in the early part of winter, after the cows are taken from grass, than at a later period; and, if it is resorted to with milch cows, will inevitably lead to a falling off in the milk, which no good feed can afterwards wholly restore. It is desirable, therefore, to know what can be used instead of his best English or upland meadow hay, and yet not suffer any greater loss in the flow of milk, or condition, than is absolutely necessary. In some sections of New England, the best quality of swale hay will be used; and the composition of that is as variable as possible, depending on the varieties of grasses of which it was made, and the manner of curing. But, in other sections, many will find it necessary to use straw, and other substitutes; and it may be desirable to know how much is required to form an equivalent in nutrition to good meadow or English hay. The following brief table of nutritive equivalents will be convenient for reference: ------------------+-----------+----------------- | | Percentage | | of Nitrogen. | Nutritive +--------+-------- |equivalent.| Dried. |Undried. +-----------+--------+-------- 1. Meadow hay, | 100 | 1.34 | 1.15 2. Red Clover-hay,| 75 | 1.70 | 1.54 3. Rye-straw, | 479 | 0.30 | 0.24 4. Oat-straw, | 383 | 0.36 | 0.30 5. Wheat-straw, | 426 | 0.36 | 0.27 6. Barley-straw, | 460 | 0.30 | 0.25 7. Pea-straw, | 64 | 1.45 | 1.79 ------------------+-----------+--------+-------- The following is the composition of these several substances, in which their relative value will more distinctly appear: --------+------+-------+--------+-------+------- | |Starch,|Gluten, | | | Woody| Gum, |Albumen,| Fatty | Saline Water. |fibre.| Sugar.| etc. |matter.|matter. --------+------+-------+--------+-------+------- 14 | 30 | 40 | 7.1 | 2 to 5|5 to 10 14 | 25 | 40 | 9.3 | 3 to 5| 9 12 to 15| 45 | 38 | 1.3 | | 4 12 | 45 | 35 | 1.3 | 0.8 | 6 12 to 15| 50 | 30 | 1.3 | 2 to 3| 5 12 to 15| 50 | 30 | 1.3 | | 5 10 to 15| 25 | 45 | 12.3 | 1.5 |4 to 6 --------+------+-------+--------+-------+------- From these tables it will be seen that, taking good English or meadow hay as the standard of comparison, and calling that one, 4.79 times the weight of rye-straw, or 3.83 times the weight of oat-straw, contains the same amount or nutritive matter; that is, it would take 4.79 times as much rye-straw to produce the same result as good meadow hay.