208 U. S. BUREAU OF FISHERIES 
feed manufacturers have expressed a desire for sufficient information 
to determine when a fish meal is suitable for animal feeding and when 
it is only of fertilizer grade. Since decomposition or spoilage of any 
food or feed product is a progressive change and a relative term, and 
since it is well known that some types of decomposition are not 
objectionable or harmful, there was a considerable demand from both 
producing and consuming industries interested in fish meal that the 
Bureau’s technologists investigate the possible toxic properties of 
fish meals prepared from partially decomposed fish or under other 
adverse conditions of manufacture, handling, or storage. 
Therefore, during 1938, chemical and pharmacological studies were 
inaugurated on this project. The fish meals used in these tests were 
menhaden, California sardine or pilchard, and so-called white fish meal 
prepared from trimmings of cod, haddock, and other ground fish. 
Good commercial meals of varying quality and experimentally spoiled 
meals were fed to groups of albino rats and baby chicks. There were 
no significant differences in gains in weight and food intakes of rats 
fed the commercial and the spoiled meals. Groups of chicks fed the 
spoiled meal in an otherwise purified diet generally grew faster and had 
a decreased mortality rate over groups fed the commercial meals. 
Apparently, conditions in the spoiled fish meals favored the bacterial 
synthesis of vitamin K and possibly of other vitamins required by the 
chicks. Data thus far indicate that the spoiled fish meal can be used 
to advantage as a protein supplement in any ration adequately 
balanced in vitamins and minerals. 
MANUFACTURE OF FISHERY BYPRODUCTS 
Studies in this field cover the utilization of the various byproducts 
of the fisheries and methods for testing and improving their quality. 
UTILIZATION OF SALMON CANNERY TRIMMINGS 
For the past several years the Bureau has devoted a portion of its 
technological activities to a study of the problem of utilizing salmon 
cannery waste. During this time a rather complete survey has been 
made regarding the nature and the composition of salmon waste, 
information has been obtained which fully demonstrated the value of 
salmon oils as sources of vitamins A and D, data have been obtained 
on the varied chemical and physical properties of these oils which 
may be expected to elucidate their utility in technical consumption, 
and assistance has been given the industry in developing an edible 
oil which can be added to the canned product. This line of attack has 
been followed because it was believed a better understanding of the 
nature and potential utility of salmon waste and the products avail- 
able therefrom would stimulate a natural expansion in utilization. 
However, due to the varied economic and technical obstacles pre- 
vailing throughout the salmon-canning industry, the general line of 
study outlined above could not be expected to be of definite help in 
all situations. Also, increasing utilization of waste material for the 
manufacture of edible canning oil has led to new problems regarding 
the best methods of converting the unused waste portions into their 
most valuable state. Therefore, after having provided a general 
background, attention is being directed to the development of methods 
