salmon ( Oncorhynchus gorbusha ) viscera from Puget Sound and Alaska. 

 However, there were variations in the ccmposition of different organs of 

 the viscera. The eggs, which Robinson, Palmer, and Burrows (1951) found 

 produced more growth than any other parts of the viscera, did not have a 

 high vitamin content but contained the most protein and fat. The milt, 

 digestive tract, amd liver all contained about the same amount of protein 

 and fat as the whole viscera. The liver and digestive tract had a higher 

 vitamin content than either whole viscera or eggs. 



Burrows, Robinson, and Palmer (1951), and Robinson, Palmer, and 

 Burrows (1951), found that yellowfin tuna ( Neothunnus macropterus ) liver 

 apparently contains anti-anemia factors and thus is of potential value 

 as a component of hatchery diets. The protein and vitamin contents of 

 yellowfin tuna liver were comparable to that of beef liver. 



Hake ( Merluccius productus ) , whole cod (Gadus macrocephalus) . and 

 halibut ( Hippoglossus stenolepis) sawdust, each of vrtiich Robinson, Palmer, 

 and Burrows (1951) > and Robinson, Payne, Palmer, and Burrows (1951) > found 

 could be substituted for hog spleen but not for hog liver in the hatcheiy 

 diets, had vitamin contents in the range of the hog spleen rather than 

 of the hog liver. Halibut sawdust and whole cod contained less protein 

 and considerably smaller amounts of the vitamins than did the beef liver. 



With the exception of the meals prepared by acetone extraction, the 

 vitamin contents of the salmon viscera meals were essentially the same. 

 The acetone-extracted meal contained smaller amounts of the vitamins. 

 . However, Robinson and his co-workers (1951 (B)), found that the steam- 

 heated, vacuum-dried viscera meals produced better growth in fish than 

 did the viscera meals manufactured by other methods. Since no significant 

 differences in composition were evident, the additional growth prob.bly 

 was due to factors other than those tested. The retention of these 

 additional growth factors may have been due to the fact that the steam- 

 heated, vacuum-dried meal required no precooking. 



Salmon offal meals contained a slightly smaller quantity of the 

 vitamins than the salmon viscera meals; however, the important difference 

 was that less protein and more fat were present. The flame-dried offal 

 meal had a lower vitamin content than did the offal meals dried in an air 

 tunnel at 100° or 145° F. 



Meal prepared from decomposed offal showed about the same proximate 

 composition and vitamin content as the meals prepared from fresh offal. 



Flame-dried mackerel offal meal and flame-dried salmon offal meal had 

 about, the same protean and vitamin contents. 



Tne meal from blue crab, which Robinson, Palmer, and Burrows (l95l) 

 found was effective xn preventing anemxa and deci-easing mortality in fish. 



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