identical diet or one supplemented by 10 percent meal. It was assumed 

 that the anemia was caused by a difference in the nutritional require- 

 ments of Chinook. To increase the vitamin content of the diet, the hog 

 spleen was eliminated from the meat-viscera mixture and a diet consisting 

 of one third each of beef liver, hog liver, and salmon viscera was 

 created. This diet was fed for the last two years to the production 

 Chinook and the fish did not develop an anemia o As this ration was fed 

 during different years and to different stocks of fish without adequate 

 control groups, numerous variables were introduced which made it impos- 

 sible to draw any conclusions from the results. The chinook experiments 

 conducted this season were designed to determine if nutritional differ- 

 ences existed between Chinook and blueback salmon. 



On the assumption that nutritional deficiencies would develop, the 

 standard meat-viscera mixture (Table 5, Diet 1-C) was supplemented with 

 5 percent of crab meal (Diet 2-C). The work of McLaren (19U7) indicated 

 that crab meal might contain some unknovm nutrient essential to the 

 normal development of rainbow trout. Experiments at this laboratory 

 (Robinson et al. 195la, 195lt)) indicated that crab meal contained some 

 anti-anemic~properties when fed to blueback salmon. The total scrap of 

 the blue crab ( Callinectes sapidus) was the source of this flame-dried 

 meal. The chinook ration (Diet 3-C), consisting of one third each of 

 beef liver, hog liver, and salmon viscera was fed for purposes of com- 

 parison with the meat-viscera control (Diet 1-C). The chinook ration 

 was supplemented with 10 percent of vacuum-dried salmon viscera meal 

 (Diet U-C) during the second 12 weeks of feeding and with 5 percent of 

 crab meal (Diet 5-C) for the entire period. The salmon meal supplement 

 was added to determine if the addition of this meal would be a contribu- 

 tory factor in^, the development of an anemia. Salmon eggs were substitu- 

 ted for salmon viscera in the chinook ration (Diet 6-C) to measure the 

 contribution of eggs in this combination. 



The results of these feeding trials were not as anticipated. The 

 standard meat-viscera control (Diet 1~C) proved entirely adequate for 

 Chinook salmon. The rate of growth was significantly greater than that 

 of the fish fed the chinook ration (Diet 3-C) and no anemia was indi- 

 cated. Crab meal made no measurable contribution to the growth rate or 

 hemoglobin content of the blood in either the supplemented meat-viscera 

 mixutre (Diet 2-C) or the chinook ration (Diet 5-C). The variation in 

 hemoglobin content which appears to exist is believed to be but a normal 

 biological variation since no anemic fish were encountered in any of 

 these diets. The addition of vacuum-dried salmon-viscera meal to the 

 Chinook ration resulted in a significant Increase in the growth rate 

 without the development of an anemia. Salmon eggs substituted for 

 salmon viscera in the chinook ration (Diet 6-C) did not result in an 

 additional growth response. The failure of salmon eggs to increase the 

 grovrbh rate is believed to be due to the poor feeding consistency of 

 the diet rather than the inability of the fish to utilize the protein. 



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