FISHERY INDUSTRIES OF THE UNITED STATES, 1938 211 
Husbandry at the State College of Washington, the Bureau’s Division 
of Fish Culture, and the School of Fisheries at the University of Wash- 
ington. 
fiiidics carried on by the Division of Fish Culture and the Uni- 
versity of Washington in recent years have resulted in the preparation 
of a fish meal especially suitable for fish feeding. During the year 
technologists of the Division of Fishery Industries have cooperated 
in production studies in order to clarify the steps in preparation 
responsible for the improved nutritional properties and to determine 
means of obtaining the same feeding effectiveness by a simpler process 
of manufacture. The results indicate that the preservation of water- 
soluble, heat-sensitive extractives contributes to the improved feeding 
properties and this can be accomplished in simple dry rendering 
equipment operating under reduced pressure. The studies are being 
repeated, since the final conclusions may provide the basis for future 
fish-food plants to be installed by the Bureau and other agencies 
engaged in fish-cultural work. 
STUDIES ON FAT IN FISH MEAL 
This project was begun in 1937 and consists of collaborative work 
of various Government laboratories in the development and gradual 
improvement of methods of analysis sponsored and coordinated by the 
Association of Official Agricultural Chemists. Specifically, present 
studies involve methods of determining oi! or fat in fish meal more 
accurately than existing methods permit. A progress report on the 
work was prepared and presented at the annual meeting of the Assc- 
ciation of Official Agricultural Chemists in November 1938. The 
accuracy and efficiency of various chemical or organic solvents for 
determining the amount of oil or fat in fish-meal samples by solvent 
extraction were tested. Thus, this report contains a table showing 
the percentages of oil extracted by the various solvent reagents under 
differing conditions. These figures are of interest to the analytical 
chemist in determining the comparative accuracy of these solvents in 
making analyses of this kind. 
CHEMICAL PRESERVATION OF FISH AND FISH WASTE 
As described in the 1937 annual report of this Division, this project 
was established by the Bureau as a cooperative arrangement with the 
Aquacide Co., Washington, D. C., and the studies are being conducted 
by research associates employed by that company and stationed in 
the Bureau’s laboratories. The work consists in the development and 
application of chemical compounds for preserving fish livers, cannery 
trimmings, scrap and other fish waste, either temporarily until these 
materials can be transported to a central point for further mechanical 
processing or reduction, or as a permanent preservative in a few 
instances. Most of the work in 1938 was devoted to the application 
of a chemical solution, developed by this company, to the preservation 
of dogfish livers landed at isolated points for subsequent shipment to 
central. fish-oil rendering plants. 
About 1,500 barrels of dogfish livers were preserved by treatment 
with a formaldehyde-soda-ash compound, and, at the end of 9 months 
of storage, were found to be in good condition. The treated livers 
