The 19h9 experiment consisted of three diets xidth the same meai 

 viscera base of beef liver^ hog liver, and hog spleen at 22,2 per cent 

 each and s-lmon viscera at 33 ^U per cent. The hog liver and beef liver 

 were dyed and fliikey. The hog spleen was fit for hioman consumption 

 and therefore not dyed. The salmon viscera was obtained from hand= 

 butchered Coliirabial River chinook salmon (Oo tschawytscha ). This 

 salmon viscera contained the gonads, livers, air bladders^, and digestive 

 tracts. To this common meat-viscera base, 10C° tunnel-dried salmon 

 viscera meal was added during t^e fblloT-d.ng periods in the different 

 diets; Diet 2 contained meal throughout the experimental period of 

 2k weeks. Diet 13 contained no meal at any time, and Diet lU contained 

 meal only when the water temperatures were 50° F. or above. The 

 temperatures were 50° F, or above for approximately 10 weeks from 

 July 11 to September 13o Within .he described periods for the dif- 

 ferent diets, the meal was added at the rate of 10 per cent with a 

 corresponding proportional reduction in each of the original components 

 of the meat-viscera base. 



The results of this test on the effect of salmon viscera meals at 

 different water temperatrrres substaati.ated the results achieved in the 

 19 [t8 test. At the end of the cold-water period, each of the lots of 

 fish being fed the diets without meal had a significantly greater 

 mean lot weight than the group being fed the diet with 10 per cent 

 salmon viscera meal. The mortalities of the lots of fish being fed 

 the non -meal diets during this peridd were only' 8,6 per cent and 

 6.9 per cent respectively (Table 3). The mortality percentages are 

 in sharp contrast with the mortality of 31.6 per cent sustained by 

 the fish on Diet 2 which included 10 per cent meal, -hese mortality 

 percentj^ge'S seem to establish, quite soundly, the validity of the 

 contention that salmon waste meals at the rate of 10 per cent will 



increase the i^ortality of blueback salmon significantly during a 

 period of water temperatures averaging about h^° F, 



•^uring the warm water period, the addition of salmon waste meals 

 showed no deleterious effect on survival. The gain produced by the 

 inclusion at this time of 10 per cent of 100 tunnel=dried salmon vis- 

 cera meal in Diet lU was responsible for the higher meal lot weight of 

 the fish on this 'lelt as compared with the significantly lower mean 

 lot weight of the fish still on the meat-viscera mixture. Diet 13. 



There is some question of exactly vihj salmon meal increased the 

 mortalities during the cold water period. There were no signs of 

 disease. The usual deficiency symptoms were lacking except that some 

 small anemic fish did appear. The size of the fish in the mortality 

 was noteworthy--invar:i.ably these fish were the smallest in the lot. 



