feeding trials, a similar diet containing salmon viscera meal instead 

 of crab meal induced an acute anemia toward the end of the experiment. 

 No anemia was produced by including crab meal in this diet as was the 

 case when salmon viscera meal was used. 



The possibilities of crab meal were explored further in the hog 

 liver-salmon viscera group. Here when crab meal was used in place of 

 salmon viscera meal or in combination with this same meal, the anemic 

 tendencies were prevented which vrould have developed if the control 

 diet J, Diet 6, is a reliable index (Table 1). This control diet, with 

 20 per cent salmon meal, caused a marked anemia in 19^8 and a slight 

 anemia in the present trials, so without too much doiibt ths conclusion 

 concerning the comparison of the anti-aneitdc properties of crab meal 

 and salmon viscera meal is valid. 



'^he examination of the two diets with the meat viscera base, 

 •^iets 10 and 11, disclosed no anemic tendency. This result is to be 

 expected since the performance of Diet 10 in previous years has 

 shown no evidence of anemia. 



In addition to its effect on anemia, crab meal contributed to 

 higher survivals than did salmon viscera meal. In Table 6, Diet $ 

 with 20 per cent crab meal produced the lowest mortality rate in this 

 group during the cold-water period. The next lowest mortality rates 

 during the cold-water period were made with equal parts crab meal and 

 either salmon viscera meal (Diet 7) or salmon offal meal (Diet 11) « 

 Although the results secured with Diets 5 and 7 are not strictly 

 comparable to those secured with Diet 11 because of the different 

 food bases used, a definite trend is present — crab meal in these 

 diets caused less mortality than did the salmon meals. During the 

 warm water period, neither crab meal nor salmon meal had a measurable 

 effect on mortality. 



The weight gains duriag the cold-water period are to a great 

 extent obscured by the varying mortalities, but it may be said about 

 these particular diets that crab meal, due to its effect on survival, 

 and perhaps for other reasons, had a tendency to increase the mean 

 lot weights. During the warm-water period, the results were obscured 

 again because, in addition to the varied mortalities incurred during 

 the previous cold-water period, the viscera meal or offal meal. Diets 

 7 and 11, had a tendency to produce more growth, although not always 

 significant, than either crab meal, salmon viscera meal, or offal meal 

 alone (Diets 5, 6, and 10) during either period of water temperature. 



In conclusion, the experiments indicated that with these particular 

 diets crab -neo-l produced no anemia as did salmon viscera meal during the 

 cold-water period. Also by the same comparison, crab meal decreased 

 mortality and possibly contributed to growth in combination with salmon 



16 



