FEEDING AND REARING FISHES. 
297 
tlie Virginia Agrionltural and Meclianical College, is my autliority for saying that 
‘‘about 1.] per cent dry food substances of the live weight is reckoned good keep for 
mature live stock.” 
It will be noticed that these allowances are for di-y substances only. In an 
attempt to make a comparison between the food allowances for men and cattle and 
fishes the liquid substances have purposely been omitted. This is impossible of 
calculation for the fishes. It wdll vary constantly with the character of the water, 
the soil over which it drains, and the season of the year. It may roughly be assumed 
that the sustaining elements of the coffee, tea, milk, etc., entering into the food of the 
warm-blooded animals is replaced or compensated for by the insect life present to a 
greater or less extent in or over most waters. 
A study of the foregoing table and quotations giving the feeding methods followed 
at the various fish-cultural establishments shows that the average of the food allowance 
is Gi ]>er cent of the w'eight of the trout. Last year I exY>ressed the opinion that this 
allowance was in excess of the requirements. This judgment wars possibly hasty, 
for it is to be noticed that in every instance the amounts are for wet foods; that is, 
for liver, meat, curd, etc., in a more or less moist condition. The limited data at my 
command shows that 1 pound of liver contains 24 per cent of dry substance; 1 pound 
of horseflesh contains 23 per cent of dry substance, and 1 pound of curd contains 45 
per cent of dry substance. From tests I find that 1 pound of mush made from ship- 
stuff, or shorts, contains 28 per cent of dry substance. Hence we would have as the 
average 2,^- per cent of dry substance given to fish as against 1 J per cent allowed cattle 
and men not at work. 1 think it will be admitted that this is too much. Not only is it 
contrary to analogy, but the experience of the Neosho Station has proven, to my 
satisfaction at least, that it is in excess of all re(piirements. In the year which gave 
us the highest degree of satisfaction the food allowance was 3 per cent wet sub- 
stances, or 0.75 per cent dry substances. The trout at one year old in that season 
attained a length of 0 inches and a weight of 51. 8C pounds per 1,000 fish. On page 
300 will be found the schedule of the food allowance for these fish during each mouth 
of the year reduced to a daily allowance per 1,000 fish. 
From the foregoing, and from other observations, I am of the opinion that 1 per 
cent of the live weight per day of dry substances will be found ample for trout, and 
that an amount much in excess of this would be prejudicial to the development of 
the fish. But it must not be supposed that this allowance of any or all substances 
will be found to produce the desired result. As before intimated, the contrary will 
sometimes happen. Man could exist but a short time on li per cent of his weight on 
bread or meat alone. Not only this, but it has been pointed out that all food substances 
vary, in the quality of their constituents, with the soil and season. No matter how 
perfect the premises and how careful the reasoning, safe laws of dietetics, for man 
or fish, will be found to require a great degree of elasticity. 
Certain conditions are necessary to make an artificial f )od generally accejttable. 
The supply must be convenient and certain; the cost must be such as not to entail 
too great an expenditure for the value of the crop of fish; it should be a substance of 
easy and rapid preparation, and, above all, the chemical composition, or proportion 
of nitrogenous and nonnitrogeiious constituents, should be in accordance with the 
requirements of the fishes to be fed. In determining the food to be used at any 
hatchery all of these factors must be considered in connection with the conditions of 
