farmer to sell off nearly half of his
cows, and to feed the whole of his hay and roots hitherto used into the
remainder.

An animal, to be fully fed and satisfied, requires a quantity of food in
proportion to its live weight. No feed is complete that does not contain
a sufficient amount of nutritive elements; hay, for example, being more
nutritive than straw, and grains than roots. The food, too, must possess
a bulk sufficient to fill up to a certain degree the organs of digestion
of the stomach; and, to receive the full benefit of its food, the animal
must be wholly satisfied--since, if the stomach is not sufficiently
distended, the food cannot be properly digested, and of course many of
the nutritive principles which it contains cannot be perfectly
assimilated. An animal regularly fed eats till it is satisfied, and no
more than is requisite. A part of the nutritive elements in hay and
other forage plants is needed to keep an animal on its feet--that is, to
keep up its condition--and if the nutrition of its food is insufficient
for this, the weight decreases, and if it is more than sufficient the
weight increases, or else this excess is consumed in the production of
milk or in labor. About one sixtieth of their live weight in hay, or its
equivalent, will keep horned cattle on their feet; but, in order to be
completely nourished, they require about one thirtieth in dry
substances, and four thirtieths in water, or other liquid contained in
their food. The excess of nutritive food over and above what is
necessary to sustain life will go, in milch cows, generally to the
production of milk, or to the growth of the foetus, but not in all
cows to an equal extent; the tendency to the secretion of milk being
much more developed in some than in others.

With regard, however, to the consumption of food in proportion to the
live weight of the animal, it must be taken, in common with all general
principles, with some qualifications. The proportion is probably not
uniform as applied to all breeds indiscriminately, though it may be more
so as applied to animals of the same breed. The idea of some celebrated
stock-raisers has been that the quantity of food required depends much
upon the shape of the barrel; and it is well known that an animal of a
close, compact, well-rounded barrel, will consume less than one of an
opposite make.

The variations in the yield of milch cows are caused more by the
variations in the nutritive element