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PRELIMINARY REPORT ON A DRILL SAMPLING DEVICE FOR FISH LIVERS
By Charles F. Shockey and F. Bruce Sanford*
Sampling fish livers to determine their Vitamin-A content is a more difficult problem than is generally realized. The oil content and Vitamin-A potency vary greatly from one liver to another and even in different portions of the same liver a considerable variation occurs.
of the various currently used, or proposed, sampling methods, that in which the livers are disintegrated and then stirred to homogeneity is probably the most accurate and universally applicable. However, there are certain difficulties with this method which make desirable an alternative procedure. The mechanical equipment involved is costly and is too heavy for easy portability between sampling points. Furthermore, after the livers have been ground, they lose their identity as to species and may therefore become less salable. There is also a question as to the stability of the Vitamin-A in livers if they have had air mixed into them during the homogenization process. In an attempt to overcome these difficulties, a sampling device has been developed which will be useful with fresh livers whenever results within 10 or 15 percent of the true values are satisfactory.
The sampling device herein described is light in weight, simple to construct, and in
, expensive. It consists of a small electric drill with a speed of 1700 R.P.M., a long wood auger of the solid center type, and a steel tube (Figures 1 and 2). The tubing is 19 inches long and 19/32 inches inside diameter. The lower end of the tube is somewhat irregular and sharpened. It is fitted with a bracket and a clamp on the upper end making it possible to attach or remove it from the drill at will. An eight-ounce wide mouth jar lid with a 1/16 inch hole drilled in it for an air vent is attached by a side arm pipe near the upper end of the tube. By means of this lid, a bottle can be secured to the device for the purpose of receiving the sample.
The auger is 9/16 inches in diameter and long enough to extend approximately 1/8 inch beyond the end of the tube when it is in use. As will be noticed in Figure 1, the tip of the auger is altered so that the screw, the false spiral, and both spur cutters are removed, leaving only the single continuous spiral to cut the sample and to carry it up the tube to the sample jar. A cork is used as a gasket to prevent the sample from going out the upper end of the tube. The lip of the auger is well sharpened so that it will pierce the livers and not push them aside. * Technologists, Fishery Technological Laboratory, Seattle, Washington,
The use of the sampling device is not difficult, as it is employed simply as a drill. In the case of small livers it is important that the thrusts be made not faster than one every three seconds, as otherwise there is a tendency for the very small livers to be pushed aside. After each sample has been taken, the eight-ounce jar is removed, the tube cleaned, another jar attached, and the device is ready for the next lot of livers.
An indication of the accuracy of the device can be obtained from an examination of Table 1. In this table, it has been assumed that the ground sample, which was obtained by disintegrating the livers and then stirring them until homogeneous, gave the correct results; and that the drill sampling method erred to the extent of its deviations from this procedure. This assumption appears to be well founded, since in a number of preliminary experiments, duplicate ground samples agreed to better than two percent or within the error of the method of analysis. In general, the accuracy of the sampling device will be a function of the number of thrust's made into the liver materia, the larger this number, the greater the accuracy.
Table I--The Accuracy of the Sampler
Deviation of Drill Sample
from Ground Sample
Per lb. No. Oil oil liver Sampler Oil oil
liver Oil oil liver Percent U.S.P. Millions of Number Percent U.S.P. Millions of Percent Percent Percent Units U.S.P. Units
DOGFISH (Squalus suckleyi) 1 70.2 24,400 7.78
-13.1 -10,1 68.3 30,100 9.33
69.3 30,000 9.44 +1.5
-0.3 + 1,2 3 70,4 14,000 4.47
+ 7.4 4
61.6 28,500 7.97 -1.0 + 3.3 + 2.3 5 71.8 3,960
. 5.1 - 3.1 6 67.7 4.24
69.5 12,000 3.79 +2.7 -13.0 -10.6 7* 3,480 0.99
+ 7.5 + 9.1 Average error without regard to sign
5.0 - 9.4
- 2,1 10 55.4 146,000 36.7
-_4.1 1.9 Average error without regard to sign
4.2 4.5 *These livers were sampled while frozen,
The proposed sampling device, even in its present stage of development, should have utility, especially with firm, fresh livers or soft-frozen livers. However, a further study is. being made in the belief that, although the principle of the device seems to be fundamentally sound, yet its application to either fresh or frozen livers can be considerably improved.
FOOD SUPPLIES OF U. S., CANADA AND GREAT BRITAIN COMPARED
A report comparing the food supplies of average U, S., Canadian and British citizens was made public April 25 by the Combined Food Board. The report is the most complete and reliable which has been made to date of supplies of food for civilian consumption in the three countries. Per capita 1943 food supplies in each country were compared with pre-war supplies and with supplies in the other two countries in terms of kinds of food, calories, minerals and vitamins.
The pre-war diets of the three countries were similar in commodity composition and nutritive value, though the United States had appreciably more dairy products, poultry, eggs, and fruit than the United Kingdom and much more fruit and vegetables than Canada.
Summary of Per Capita Supplies of Food Moving Into Civilian Consumption, U. s., 1935-39 to 1943-44
Pounds per capita per annum Item
Percentage of pre-war 1935-39 1940 1941 1942 1943 1943-44 1935-39 1940 1941 1942 1943 1943-44 Fish, cured, fresh, and frozen: Other fish (fresh fillet basis) 6.3 5.61 6.31 5.2 3.8
100 891 100 83 60 67 Shellfish (without shell)
1.1. 1.1 .9 1.1 1.0 1.1 100 100 821 100 91 100 Fish, canned
5.0 4.214.91 3.4 2.5 2.6 100 841 98 68 50 52 Total (edible weight)... 12.4 10.9220.127.116.11 7.9 100 88 981 78059 64
In Canada, the report states, 1943 food levels were very close to those in the United States, with supplies of most foods in both countries at or above 1935-39 levels. In general, farm production increases in Canada have kept pace with the marked increases which have occurred in military and export requirements. In the United States, supplies for civilians increased substantially in 1940 and 1941 and they are still somewhat above the 1935-39 level. Summary of Per Capita Supplies of Food Moving Into Civilian Consumption, Canada, 1935-39 to 1943 Pounds per capita per annum
Percentage of pre-war Item
1935-391940 1941 1942 1943 1943-44 1935-3911940 1941 1942 1943 1943-44 Fresh and frozen fish 8.8 8.8 4.9 4.59 4.5
100 100 56 51 51 Shellfish .. .4 .4 .5 .3 .3
100 1001 125 75 75 Canned fish 2.7 2.71 2.94.4 4.4
100 100 1071 163 163 Total (edible portion) 11.9 11.91 18.104.22.168 ..... 100 100 7077
In the United Kingdom, despite very large increases in food production, the reduction of imports has lowered supplies of most foods sharply below 1935-39 levels. By the end of 1940, the United Kingdom consumption of meat, fats, and sugar had fallen sharply. In the first half of 1947, the food intake fell to its lowest wartime level and general health and working efficiency showed definite signs of impairment. Improvement resulted in the second half of 1942, when Lend-Lease supplies began to reach British consumers. The report emphasized the importance to the United Kingdom of the increased supplies of food shipped from Canada and the United States.
Sumnary of Per Capita Supplies of Food Moving Into Civilian Consumption,
United Kingdom, 1934-38 to 1943-44
Pounds per capita per year I ten
Percent of pre-war level 1934-38 1940 1941 1942 1943 1943-44 1934-38 1940 1941 1942 1943 1943-44 Fish, fresh and frozen, white
64 54 54 Fish, fresh and frozen, fatty
53 59 71
62 62 62 69 62 Canned fish 3.6 5.2 3.4 2.8 3.0 3.5 100 144 94 78 83
97 Total (edible wt.) 24.8 17.115.5 16.6 14.9 15.1 100
69 63 67 60 61
Supplies of fish, In Pounds Per Capita Per Year, Moving Into Civilian Consumption
change 1943 Kingdom
Supplies in Canada as percentage of United
Fish (fresh, frozen, and cured)
fresh fillet basis .... Shellfish (without shell) Canned fish
Total (edible weight)
Lb. Lb. Lb. Lb. Lb. Lb. % % 1 %
Blagt sel Canada
30 176 126
Tabular material selected from the report is reproduced in this article. An excerpt covering fish consumption, based on these tables, follows:
The average pre-war consumption of fish (other than canned fish and shellfish) in the United Kingdom, was more than three times as great as that in the United States and more than twice that of Canada; in 1943 it was still over 2 times the United States level and more than double the canadian figures. The consumption of canned fish, as a matter of policy, has been more severely reduced in the United States than in the United Kingdom. But consumption in Canada on the basis of current estimates has increased. Canned salmon, however, was not being made available to civilian consumers in Canada throughout 1942 and 1943, as the entire pack was consigned to the United Kingdom. None of the items in this group is rationed, with the exception of canned fish in the United States and the United Kingdom, but fresh fish, other than herring, is subject to controlled distribution in the United Kingdom,
Conversion Factors from Actual Weights to "Common Denominators"
Basis of factor
landed to wet fillet weight. 1.0 1.0 1.0 Original statistical data as
wet fillet weight, or weight 1.0
1944 PACIFIC HALIBUT FISHERY REGULATIONS ISSUED
A memorandum issued by the International Fisheries Commission early in April lists the following changes in the 1944 Pacific Halibut Fishery Regulations from those of last year:
Section 2 (a). The catch limit for Area 2, which includes the waters off the coasts of Washington, British Columbia, and southeastern Alaska, is increased from 23,000,000 to 23,500,000 pounds but the limit of 27,500,000 pounds for Area 3, off the coast of middle and western Alaska is unchanged.
Section 2 (b). A length limit of 26 inches for fish with heads on is substituted for the previous equivalent weight limit of 5 pounds 13 ounces for dressed halibut with their heads still on. vious 5-pound weight limit is retained for dressed fish with their heads removed, as for marketing.
Section 4 (a). Reference to "bottom nets or trawls" is eliminated because of the prohibition of net fishing in Section ll.
Section 4 (e). The pre-season validation of halibut licenses for fishing in Areas 1 or 2 is limited to 3 days and in Areas 3 or 4 to 5 days before the opening of the fishing season.
Section 5 (a). To assure uniform interpretation of what constitutes "salable fish of other species," for purposes of computing the amount of halibut that may be retained by vessels fishing under permit, "salable fish" is limited to that "actually utilized." Section 5 (b). The revision of size-limits in Section 2 (b) is also applied to halibut caught under
Section 5 (e). Provision is nade for the possible termination of the landing of permit halibut earlier than the specified date of November 30, which was adopted provisionally in 1943.
Section 10, The prohibition of the use of dory gear, effective in Areas 1 and 2 since 1935, is applied also to Areas 3 and 4.
Section 11. The prohibition against the retention of balibut caught by boats with set nets on board is extended to boats carrying any type of net, except bait nets which are used only for the capture of bait.
Section 14. To provide against the eventuality of the fishery being left without regulation because of delay in securing the approval of regulations for the succeeding year, the regulations are made effective until superseded by subsequently approved regulations,
The 1944 halibut fishing season began at 12:01 a.m. the morning of April 16. The only deep-sea fishery under international regulation, the halibut fishery is controlled jointly
This year, by the United States and Canada through the International Fisheries Commission. the Commission's regulations which have been approved by both the President of the United
States, and the Governor-General of Canada, will allow fishermen to take 51,000,000 pounds-a half million pounds up from the quota of 1943. No specific date has been set for closing of the season; it will end when the quota has been caught.
FISH INDUSTRY MEETS WITH WFA
The Fresh and Frozen Fish Industry Advisory Committee, working with Government agencies on fresh and frozen fish programs, held its first meeting with War Food Administration and other Government officials in Washington, D. C., April 13.
The group was organized to 'advise the Government on distribution, storage, transportation, manpower and other problems.
The fishing industry may expect slightly more fish this year than in 1943 as a result of more fishing vessels being made available through priorities and the release of boats by the War Shipping Administration, the committee was told by the Fish and Wildlife Service of the Department of Interior.
This year's production is expected to be slightly more than the 4 billion pounds (round weight basis) produced last year. The 1944 goal of over 5 billion pounds is not expected to be reached because of still existing manpower and boat shortages. From the 1943 catch, about 1-1/3 billion pounds were sold as fresh and frozen fish. The remainder was about equally divided between canned fish and other fish products.
Food Distribution Orders 70 and 90, which restrict storage space, are expected to make more space available for frozen fish this year than during 1943, the WFA reported. The supply of ice for preserving fish is also expected to be more favorable.
No improvement in the tight supply of cardboard containers is foreseen but more wooden containers are expected to be available to the industry within the next month. The committee also discussed transportation, facilities and equipment, and manpower problems.
The War Production Board announced April 20 that pine tar, a product of the naval stores industry which is now in short supply, has been placed under allocation for the first time as a schedule of the General Allocation Order M-300. Shortages in pine tar first occurred in December 1942 when AA-l ratings were assigned applications for its use in rubber compounding, rubber reclaiming, cordage for fishing nets, and oakum for the Navy shipbuilding program. The same rating also was allowed for small amounts for ship bottom paints, for oakum production for the Navy shipbuilding program, for military and civilian plumbing uses and for