From the above data it appears that the food value of salmon 

 eggs is extremely high. And the rate of growth is, in the opinion of 

 the author, above normal. Special attention is called to the results 

 obtained when fresh eggs were used. These were taken from chinook 

 salmon during the first week of June, 1921, and were not by far as 

 well developed as those used in the other experiments. On the basis 

 of our knowledge of vitamines, the explanation seems to be that 

 the riper the egg the more growth-promoting substance it contains. 

 But as only four series of experiments were completed with these 

 eggs, too narrow conclusions must not be drawn. Nevertheless it is 

 interesting to find that the percentage of daily growth of the same 

 lots of fry dropped from an average of 3.44 to 2,56 and the efficiency 

 factor from 72.9 to 57.7, with practically the same percentage of 

 food. 



It is not yet demonstrated that cold-storage salmon eggs contain 

 all the food requirements of salmon fry. The experiment inaugu- 

 rated to determine this had to be terminated prematurely. But the 

 results indicate that salmon eggs are a cheap and efficient substitute 

 for fresh meats in the hatcheries, especially on the Pacific Coast. For 

 promoting growth they appear to be the best food ever tried. The 

 author suggests that fish culturists who are within reach of a supply 

 of salmon eggs try them out as a substitute for liver or melts on a 

 limited number of fry, using liver as a control. In this manner no 

 undue risk is assumed. 



Discussion. 



Dr. G. C. Embody, Ithaca, N. Y. : The food situation on the Pacific 

 coast differs from that here. It is very difficult for those rather isolated 

 western hatcheries to get the more expensive liver, yet it has been found 

 that some such fresh food must be used. Canned salmon has been fed 

 largely but it happens that this food can be fed continuously for a few 

 days only, depending on local conditions, without producing certain dis- 

 eases. In order to prevent those diseases, the fish must be fed upon 

 fresh liver or some substitute. 



Mr. G. C. Leach, Washington, D. C. : This paper shows some very 

 painstaking investigations, and brings out most interesting information, 

 especially as to the necessity of feeding a well balanced diet. I was 

 wondering as to the advisability, however, of feeding fresh salmon eggs, 

 except in case of emergency. I believe no mention was made of feeding 

 unfertile eggs. 



Dr. Embody : These are all unfertile eggs. They are waste from the 

 canneries and are ordinarily thrown away. 



Mr. Leach : The protein content of fish eggs is very low, about 15 

 per cent in the herring. At some of our Pacific stations we once fed 

 canned herring roe without success, and as this paper goes on to show, 



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