salmon carcass was deficient in the anti-anemic factor and the 19U5 

 experiments with tuna viscera, fed freshly prepared, indicated an even 

 greater deficiency in this product. It is apparent that the re- 

 duction in the anti-anemic factor due to storage was sufficient to 

 deplete the salmon carcass diet below the minimal requirements of 

 blueback salmon „ A comparable diet, freshly prepared, proved ad- 

 equate in the 19hh experiments „ 



Only one prepared frozen diet was fed in 19u7 <■ This ration, 

 which consisted of 90 per cent salmon viscera and 10 per cent apple 

 pomace, exhibited a lower mortality and significantly greater gains 

 in the fish than did a duplicate diet prepared daily (Table a, Diets 

 11 and 12) o As the composition of the salmon viscera may have varied 

 between lots,, it cannot be concluded that storage had a beneficial 

 effect on the diet other than the possibility that the more soluble 

 components of the viscera were absorbed by the meal and, thus, were 

 made available to the fish. 



In 19U8 the stored diets consisted of the meat and viscera 

 mixture plus 10 per cent lU5-degree, salmon viscera meal and 90 

 per cent salmon viscera plus 10 per cent of the same viscera meal. 

 Duplicate freshly-prepared diets were included in the experiments 

 (Table 5, Diets 2 and 19, 15 and 20), The results of previous 

 years were not repeated in these experiments. The meat-viscera- 

 meal mixture produced an anemia which was so acute as to cause a 

 discontinuance of this lot after 16 weeks of feeding. The diet con- 

 taining the high level of salmon viscera showed evidence of a pan- 

 tothenic acid deficiency in the fish after 7 weeks of feeding. No 

 gains were made, in fact the group as a whole lost weight. Losses 

 were so severe in this lot as to force the abandonment of the ex- 

 periment after 18 weeks of feeding. Surprisingly enough, no anemia 

 was present in these fish. The results from both these diets lead 

 to the conclusion that the loss of vitamins due to storage was 

 sufficient to reduce the vitamin content of the diet below the minimal 

 requirements of the fish when the food intake was reduced due to 

 cold water temperatures. 



The results of the entire group of prepared frozen diet tests 

 indicate that prepared diets lose a significant portion of their 

 vitamin content during the cold storage period. If the original diet 

 contains more than the minimum vitamin requirement of the fish and 

 the food intake is high, the fish may receive sufficient vitamins to 

 meet their demands but when the original diet contains only a minimal 

 vitamin content or the food intake is reduced, vitamin deficiencies 

 may develop. 



It is assumed that the primary factor responsible for vitamin 

 reduction in prepared diets during storage is oxidation. The ground 

 diet has infinitely greater surface exposed to the air and, therefore, 



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