Salmon cannery waste amounts to aboat one-third the weight of 

 the entire fish. In Alaska these waste portions are in most instances 

 discarded by dumping at sea. The knowledge of a huge potential supply 

 of the waste material in Alaska, estimated at more than 100,000,000 

 pounds annually, gave impetus to the effort to find suitable means of 

 using this cannery waste. A discussion of this problem is presented in 

 a report (Jones and Carrigan 1947) entitled, "Utilization of Salmon 

 Cannery Waste — Literature Survey", Office of Technical Services Report, 

 Part One, Section One, Department of Commerce, Gac-47-17, December 1947. 



The present study deals with the critical evaluation of presently 

 used feeding materials and exploration for new feeds. This work was 

 carried out collaboratively during 1947 to 1951 inclusive by the Seattle 

 Fishery Technological Laboratory and the Leavenworth Salmon Hatchery of 

 the United States Fish and Wildlife Service. 



Carefully controlled studies on the value of raw cannery waste and 

 other feed materials at the Leavenworth Hatchery were carried out. This 

 project also included studies on meal preparation from the raw products 

 and other methods of processing and preserving the raw food material. 

 Proximate composition as well as assays for certain vitamin constitu- 

 ents of the diet components was carried out at the Seattle Fishery 

 Technological Laboratory. 



The 1947 program 



The collaborative investigations were inaugurated in 1947, late in 

 the hatchery season; therefore, the initial experiments were necessarily 

 limited in scope.. However, it was possible to run a survival experiment 

 with blueback salmon fingerlings ( Oncorhynchus nerka) to determine the 

 presence, if any, of anti-anemia factors in three different types of 

 meal prepared from salmon viscera. Growth evaluation studies were also 

 carried out on the same species with five different mixed diets composed 

 of raw feeding materials and prepared meals, and also control feeding 

 mixtures. The results of the first-year studies (Burrows, Robinson, 

 and Palmer 1951) indicated that salmon viscera produced excellent growth 

 when fed either as a single diet component or vrtien fed in conjunction 

 with meat products. It was observed that salmon viscera meals fed as 

 10 percent of the diet made a significant contribution to the growth rate. 

 These meals included a low-temperature (100° F.) air-dried meal, an 

 acetone-extracted meal (room temperature), and a flame-dried offal meal. 



Fingerlings fed salmon viscera showed good growth and were in 

 healthy condition at the end of the 12 -week experimental period, but 

 those fed salmon cannery waste minus the viscera were on the verge of 

 acute anemia at the end of this period. 



The 1948 program 



After conclusion of the 1947 experiments a more extensive investi- 

 gative program was carried out during 1948. A series of 12 different 



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