Jan. 3i, 1916 
Effects of Refrigeration on Trichinella spiralis 
823 
compared with a standardized thermometer) for a period of nearly five 
days. Trichinae isolated by dissection showed slight activity on a warm 
stage. 
The methods employed in experiments 8 to 127 and a general dis¬ 
cussion of these experiments are given in the following pages, but it 
has been found expedient in order to save space to omit from the nar¬ 
rative statements of the results. These are later set forth in tabular 
form (Tables I, II). 
In experiment 8, a leg of the rabbit referred to in experiments 4 to 6 
was inclosed in a tin can and kept in a freezer at — 2 0 F. for 43X hours 
(thermometer not compared with a standardized thermometer; one 
reading daily). The next day after its removal from the freezer some of 
the meat was chopped in fine pieces and placed in the incubator (38° to 
40° C.) in a beaker containing an artificial gastric juice (water; hydro¬ 
chloric acid, about 0.35 per cent; and pepsin—exact quantity of pepsin 
used not recorded). Unfrozen meat from the same rabbit was similarly 
treated, using a portion of the same lot of digesting fluid. After incubat¬ 
ing overnight, the sediment in the beakers was washed with several changes 
of water by decanting and settling. Trichinae from the two lots of di¬ 
gested meat were then examined in water on a warm stage and the num¬ 
ber of active and inactive individuals recorded. A guinea pig was fed 
some of the meat after it had thawed, and another guinea pig was fed 
some unfrozen meat from the same rabbit as a control, both being killed 
and examined for trichinae after the lapse of a month. 
Substantially the same methods of examination and feeding of test 
animals, with control examinations and feedings, were employed in 
experiments 9 to 22b. Meat from trichinous rats and rabbits was 
inclosed in tin cans, placed in freezers, which were maintained at various 
temperatures, and kept there for various periods. Portions of the meat 
were digested in artificial gastric juice and washed and examined as in 
experiment 8. Guinea pigs were used as test animals in experiments 9 
to 15, white rats in experiments 16 to 22b. 
In experiments 23 to 34 the carcass of a hog which had been arti¬ 
ficially infested with trichinae by feeding trichinous meat from various 
sources at intervals during a period of four months was hung in a freezer, 
the temperature of which was recorded by means of a thermometer 
(six readings daily) which had been compared with a standardized ther¬ 
mometer. The dressed carcass weighed about 150 pounds. The head 
was removed and kept unfrozen in a cooler to provide material for con¬ 
trol examinations and feedings. From time to time portions of the 
carcass were renloved for examination and test feedings. The same 
methods of examination were followed as in experiment 8. Test ani¬ 
mals, usually white or hooded rats, were fed, and one lot of rats was 
fed unfrozen meat from the same carcass as a control. 
