Diagnosis of pregnancy in mares (Thoroughbred) by the ovarian hyperemia test — Its comparative study with the male-toad and Cuboni tests

Abstract

Ovarian hyperemia in the immature rat as pregnancy test in mares (Thoroughbred) has been studied. Blood-serum samples were draw from 74 mares thirty-five to 105 days following the date of the last breeding. Two ml, were injected subcutaneously in two infantile rats, which varied in weight from 40 to 55 g . The test was read at the 24th hour. For comparative purposes, a portion of the same serum sample, of all animals, was used in the male-toad test, and urine samples collected, from 23 mares of the observed group, 102 to 151 days after service, were used in the Cuboni test. A total of 82 tests have been carried out. In 23, where a Cuboni test was also made, 22 results were in agreement with the clinical conditions, and one of them gave a false positive test with the three methods. Of 59 ovarian hyperemia and male-toad tests, only one was not in agreement giving a false negative result to both tests. A few ovarian hyperemia tests (fourteen), could be positive when carried out again between 122 and 190 days after the last breeding. Twenty-three ovarian hyperemia tests were positive with serum samples obtained between 35 and 44 days after service. These same samples were by that time still negative to the male-toad test, except one of the 40th day. However the blood serum of all these mares gave positive results with the maletoad test with samples collected some time later.