104 U. S. BUREAU OF FISHERIES 



essential difference in response was observed for the rats at any of the 

 levels studied. The amount of kelp meal included in the ration, 

 therefore, is dependent upon the cost of this product. Another 

 group of animals was fed kelp meal at levels of 15, 22}^, and 30 per 

 cent. These animals showed no ill effects from the injection of 

 diets containing these levels of kelp meal, and the rats were not affected 

 by the large quantities of salt that would be contained in these amounts 

 of kelp meal. 



Another experiment was conducted to determine the ability of 

 kelp meal to stimulate appetite. According to results obtained it 

 appears that kelp meal has a beneficial eft'ect in increasing both 

 growth and food consumption. If it can be shown that kelp meal 

 will be an aid to production of animals for early market maturity it 

 will make this product of considerable value in the field of animal 

 industry especially in the production of such products as hothouse 

 lambs, broilers, etc. 



Another experiment was conducted to determine the vitamin A 

 content of kelp meal. It was shown that this product contains about 

 one-fourth as much of vitamin A as alfalfa hay, approximately the 

 same amount of vitamin A as fresh eggs, and one and one-half times 

 as much of this vitamin as yellow corn. It is thus seen that kelp 

 meal is a fairly good vegetable source of vitamin A, but could not 

 compete with cod-liver oil and other fish oils as a source of vitamin A 

 for animal feeding. 



Further experiments were designed to test the supplementary 

 value of kelp meal when added to rations containing various protein 

 supplements. The results obtained showed that kelp meal has a 

 very favorable effect on growth when fed in diets composed princi- 

 pally of ground yellow corn and cottonseed meal. The extra growth 

 resulting from the addition of kelp meal was not due to the sodium 

 and potassium salts contained in the kelp since quantities of these 

 salts similar to the amounts contained in kelp meal were added to the 

 control diet. These experiments indicate that kelp meal has a very 

 definite supplementing effect on diets composed of corn and cotton- 

 seed meal thereby increasing the rate of growth with less food con- 

 sumption per unit gain in weight. 



PRESERVATION OF FISHERY PRODUCTS FOR FOOD 

 IMPROVED METHODS FOR HANDLING OF FRESH AND FROZEN FISH 



It is known that fish begins to deteriorate immediately following 

 death and that certain definite chemical changes occur during this 

 decomposition. These chemical changes are the same whether the 

 fish is preserved by ice, in a frozen state, or without preservation. 

 Studies of these chemical changes by James M. Lemon show that the 

 rate of decomposition is determined by the degree of preservation, 

 this being retarded by icing or freezing. With this in mind research 

 was directed toward developing a chemical means for determining 

 the condition of the flesh as to freshness, age, or stage of decomposition. 

 The method developed proved successful in the laboratory but is 

 quite complicated and requires technical skill for operation. However, 

 this method is being simplified so that it may have commercial 

 application. 



