proved inferior to beef liver in its grovrth potential when substituted 

 in the meet-viscera-meal mixture (Diets 8 and 11). No anemia had 

 developed in these fish at the end of 21; weeks of feeding. 



From the results of these feeding trials it may be concluded that 

 beef lung contained adequate amounts of the anti-aneraic factor to sup- 

 port blueback salmon for a 2U-vfeek period. A hog liver and salmon 

 viscera combination produced an excellent diet with the exception of an 

 inferior feeding consistency during vrarm-water periods. This feeding 

 consistency may be improved by the addition of either hog spleen or 

 salmon meal. Salmon eggs preserved by the addition of 0.5 percent sodium 

 bisulfite and held at room temperatures for 90 days did not produce gains 

 comparable to a similar diet containing fresh frozen eggs. Partial 

 decomposition of the eggs during storage was probably responsible for the 

 reduction in growth. Tuna liver proved an inadequate substitute for beef 

 liver in the me at- viscera-meal mixture in that a reduction in grovrth rate 

 resulted. 



Second Experiment 



The second experiment conducted with blueback salmon was begun in 

 July after the first 12-week period of the first experiment was con- 

 cluded. Information gained in the first experiment v/as used to develop 

 certain of the diets fed in the second experiment. 



These feeding trials were, on the v/hole, more exploratory in nature 

 than the first experiment. The trials consisted of evaluations of single 

 components, substitutions of these components for beef liver or hog 

 spleen in the meat-viscera-meal mixture, and tests of whale meal, salmon 

 viscera, and salmon viscera meal in combination with various meat and 

 fish products. The results of the second experiment are summarized in 

 Table U. 



The liver of the finback vfhale ( Balaenoptera physalus), supplied 

 fresh frozen through the courtesy of the British Columbia Packers 

 Association, was the source of the whale liver used in these experiments. 

 The intent of the experiments with whale liver v;as to determine its 

 possibilities as a substitute for beef liver. The use of whale liver as 

 a source of fish food had not been previously evaluated. 



Arrow-toothed halibut (Atheresthes stomias ) vras fed to determine 

 its growth potential. This species is a scrap fish occurring abundantly 

 on the Pacific Coast where it is taken in the trawl fishery and discarded, 

 it would offer a cheap, reliable source of fish food. No tests of arrow- 

 toothed halibut have been made except as they have been included inciden- 

 tally in scrap ocean fish such as was reported by Tifales (19UU)« 



Herring ( Clupea pallasii ) was included in the diet studies to 

 determine its grov/th potential and nutritional adequacy for salmon. 

 Herring, not specifically identified, has been fed to trout on the 



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