BLOOD AS FISH FOOD. 



BY Dl!. JAMES A. II i:X:> 1 1 A 1,1.. 

 "For the life of the flesh is in the blood." — Leviticus xvii, 11. 



Fresh blood, it may be said, i.< liquid HvAi. It contains a 

 large amount of albumen, and lesser quantities of fibrinc. fat, 

 and the salts of iron, lime, sodium, potassium, etc. It is food 

 in its most concentrated form. When freshly drawn and allowed 

 to stand it soon cools and separates into clots and the watery por- 

 tion called serum — the clots being fomied of the blood corpus- 

 cles and fibrine, and the serum containing the fats, salts, etc. 



The separation of freshly-drawn blood into clots and serum 

 can be prevented by briskly stirring it for several minutes, after 

 which a tilm forms upon the surface, and by keeping it in a cool 

 place it will remain fresh and in good condition for several days 



I first began experimenting with blood as fish food two or 

 three years ago, by using the blood from fresh liver, and putting 

 it into the horizontal aerating screens at the head of the hatching 

 troughs, and before the yolk-sac of the fry was absorbed. Tbis 

 was continued until the fry were swimming and old enough to 

 be fed liver emulsion in the usual way. 



It was owing to the problem of furnishing suitable food for 

 grayling fry that induced me to try fresh blood from the slaugh- 

 ter house ; and although the experiment is still in its infancy, the 

 results, so far, are most favorahle and gratifying. This season 

 it has been demonstrated that grayling fry. as soon as they begin 

 to sAdm, and when too snuill to take any other form of artificial 

 food, will readily lake fresh blood distributed on the surface with 

 a feather. 



In the feeding of trout fry. I have also sulistituted fresh 

 blood for water to dilute the liver emulsion, with the result that 

 they have done better than ever before, growing faster and 

 stronger, and with less mortality. T have furthermore diluted 

 with blood the mush for the adult stock fish. So fai- as we have 

 progressed with this manner of feeding both fish and fry, the re 

 suits are so encouraging as to warrant its continuance. The 

 food prepared in the manner stated seems to be better assimi- 



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