Embody. — Fish Meal as Trout Food 59 



was found necessary first to introduce live minnows to 

 assist in teaching the former to take the food. 



In order to obtain some definite idea of the effect of 

 this meal upon growth, one hundred rainbow trout just 

 beginning to feed were isolated May 26, 1914, in a hatch- 

 ing trough eight feet long by fourteen inches wide. They 

 were fed four times per day for the first two weeks, twice 

 daily for the next four weeks, and from then until Sep- 

 tember 26, once a day. The mean daily temperature of 

 the water during this period of four months varied from 

 53° to 61° F. 



Total weight of 100 = 283 gms., or 9y 2 oz. 



Weight of average individual^. 83 gms. 



Length of largest fish =3 inches 



smallest fish =1% " 



average fish =2A " 



CONCLUSION. 



Fish meal is a highly concentrated food containing 

 about 65% protein as compared to the 40 or 60% present 

 in the better grades of meat scrap. It consists not only 

 of the flesh but of the bones and scales of fishes, and, 

 therefore, possesses much of the mineral matter needed 

 by the living fish. It lacks the oil which has very little 

 value in the nutrition of fishes. 



It is a dry food and, therefore, must be fed in smaller 

 portions than is the case with liver. Because of this dry 

 condition and high protein content, one pound of the 

 meal is equivalent to at least two pounds of liver in nu- 

 tritive value. And yet the cost is only about three and 

 one-half cents per pound in hundred-pound sacks. 



Taking into consideration all of these facts, together 

 with the keeping qualities and the ease of preparation 

 and feeding, it seems to the writer that by its use a great 

 saving in the expense and labor of operating any trout 

 hatchery is possible. Some disadvantages may arise by 

 continued use, but such are not apparent to the writer 



