and of their Increase whilst Fattening, 
439 
quantity of dry substance of food required will vary between these 
limits, according to the exact description and quality of the food, 
and other circumstances. But 9 parts of dry substance of food for 
1 of increase in live-weight may be taken as a very fair average 
result for sheep, with good food, and good management. 
In the case of liberally-fed pigs, 1 part of increase in live- 
weight should be obtained from 4 to 5 parts of the dry substance 
of the fattening food. 
In reference to the point just referred to, it may be considered 
that oil-cakes and foreign corn will, on the average, contain rather 
more than six-sevenths, and home-grown corn, hay, &c., rather 
less than six-sevenths, of their weight of "dry substance." In the 
same way, it may be reckoned that the commoner sorts of turnips 
will, on the average, contain about one-twelfth, swedes about 
one-ninth, mangolds about one-eighth, and potatoes about one- 
fourth, of their weight of " dry substance." 
Sheep (and oxen also), fattening on food of recognised good 
quality, may give a maximum amount of increase for a given 
amount of dry substance of food, although the latter contain as 
much as 5 or even 6 parts of 7?o«-nitrogenous substance to 1 of 
idtroc/enous compounds. The latter proportion is about that in 
which the two classes of constituents exist in the dry substance 
of the cereal grains ; but in these the proportion of the non- 
nitrogenous substance which will be indigestible woody-fibre, 
will be less than in the mixed diet of sheep and oxen. Hence, 
supposing the relation of the total no«-nitrogenous to the nitro- 
genous substance to be the same in the two cases, the proportion 
of the really digestible non-nitrogenous substance will be some- 
what less in the mixed diet of these animals so fattening, than 
in the average of cereal grains. 
When pigs are fattened almost exclusively on corn, they do not 
appear to require more than 1 part of nitrogenous to about 5 or 
6 parts gross non-nitrogenous substance, to yield the maximum 
amount of increase in proportion to the dry substance of food con- 
sumed. But, since there is a less proportion of indigestible 
woody-fibre in their food than in that of sheep and oxen, it 
would appear that they can give a maximum amount of increase, 
with even a somewhat smaller proportion of the nitrogenous to 
the digestible noH-nitrogenous constituents, in their fattening 
food. 
The above proportions are those upon which the respective 
animals will frequently attain the greatest rate of increase during 
the later stages of feeding. With these the increase will, however, 
probably be very fat. In the earlier stages of growth and feeding, 
a somewhat higher relation of nitrogenous constituents is desirable, 
if not even essential, for the best progress of the animal. 
