FEEDING AND REARING FISHES. 
293 
the warning is distinctly given to the private flsh-cailturist. The greatest draw- 
back against raising large trout in a given time (possibly surpassed by an improper 
selection of breeders) is an improperly prepared food given in starvation rations to 
the fry. ‘‘As the animal is, so to speak, made during its early age, and as during 
this period its assimilating organs acQ[uire their strength and their power of absorp- 
tion, a young fish which is insufficiently fed not oidy grows very slowly, but will never 
become a fine fish.”* Time was, and unfortunately is yet Avith too many, that canni- 
balism was the only danger feared from fry on short rations. Cannibalism was a Amry 
good bugbear, but the true danger does not lie there, as it is always capable of correc- 
tion in a short time. 
The discussion of the second ajid third diets mentioned will be x>assed over for 
the present and we will proceed to look at some of the ill effects of the fourth, over- 
fattening diet, “causing a temporary or permaueiit su])pression of the reproductive 
organs, a partial or total destruction of the eyes, and inflammation of the intestines, 
frequently resulting in death,” Nearly every fish-culturist of experience has seen 
the two latter evils, “pop-eyes” and “ inflamed intestines ; ” Avhilst many have observed, 
without knowing the cause, the retardation of the genital organs of the fishes. It 
seems fairly probable that the causes known to affect the breeding of other animals 
will in like manner influence the breeding of fishes. It is a recognized principle 
among stock-breeders that an overrapid accumulation of fat is followed by partial 
or total sterility, just as conversely a remoAml of the genital organs is always followed 
by a raj)id accumulation of flesh. It would seem that the tAvo i)rocesses are intimately 
connected, and that an excess in either direction is at the expense of the other. The 
complaint has not infrequently been made: “My fish grew finely, attained a remark- 
able growth, and I fully expected a large number of eggs this season, but got very 
feAv.” It rarely or never occurs to such complainants that the Avant of eggs was due to 
the exceptionally fine growth. I have in mind a hatchery where the growth of brook 
trout Avas such that many of them lost their eyes. Eggs Avere obtained in fair rpian- 
tity, but they Avere of such low degree of A^itality tliat the season aauis counted a failure. 
When these fish Avere marketed their quality was graded low. Afore than tAveuty 
years preAuously Dr. Slack had noted a similar occurrence. In his book (Practical 
Trout Culture, p. 121) he recounts the following: 
A Avealthy geutlemau of a neigliboriiig State coiisti’ucted a well-appointed fish farm, witli \ydll- 
stocked ponds. To his surprise, during the sx>aAvuing season hut feAV eggs could he ohtaiue.d and hut 
a small percentage of these could he impregnated. AA^e were consulted in regard to the matter, and our 
first look at his fishes shoAved us plainly the cause of the trouhle. The fishes were enormous, the 
bodies greatly swelled, the whole ca’rity of the abdomen being filled with layers of fat. It appeared 
that the proprietor had for over a year fed them twice a day all they could eat, aud the result was, as 
might haA'e been esxiected, barren and unhealthy fish. 
If ever artificially reared trout sell on a parity with Avild trout — and there is no 
reason wby they can not be made to do so — it Avill not be the overfed, pop-eyed, liver- 
reeking fisli, whicli Avill produce tlie result. The danger of overfeeding is just as 
distinct aud as much to be avoided, as that of underfeeding, though obviously the 
evil effects Avill be less lasting and more restricted in results. 
Let ns now turn to the second classification, “ healthy diet, promoting normal 
groAvth aud development.” By healthy diet I mean not only the proper amount of 
food per day, but a food composed of proper constituents. It has been before inti- 
' C. RuA'cret-AATittel; II, 8. Fish Commission Bulletin, 1887, p. 210. 
