The Aschheim-Zondek test for the diagnosis of pregnancy is one of the most satisfactory, useful and accurate laboratory tests that have been developed within a generation.
Rats have largely replaced mice, used in the original test, since only one rat is used for the test rather than five mice.
The Friedman test has the advantage over the AschheimZondek test in that the results are known in from twenty-four to thirty hours rather than on the fifth day, as in the original Aschheim-Zondek test. However, when large numbers of tests are performed the inconvenience of keeping on hand large numbers of isolated rabbits is a matter of no small concern.
We have found that, if young female white rats are used, the test may be completed in thirty hours, the advantage in time of the Friedman test thus being gained without the inconvenience of keeping isolated rabbits on hand.