What Is It?
Freemartinism is defined as a sterile female bovine calf born twin to a male. Approximately 92% of females born co-twin to a male are freemartin or a non-breeder.
Freemartinism traces its origin to what happens in the womb. Specifically, it begins with the blood supply from the carrying dam to the two placental sacs of male and female calves. If there’s blood transfer between placentas, the H-Y antigen starts affecting the female calf’s neo-natal development, causing defects in her reproductive tract. As a result, the female’s reproductive system does not develop properly due to exposure to the male twin’s blood and hormones. The extent of malformation of the reproductive system will depend on when the blood transfer occurred, and at which stage of neo-natal development.
In the remaining 8% of twin females that are fertile, the blood exchange did not occur. Research shows that one in 13 female calves born twin to a male are, in fact, normal and can reproduce.
How does Holstein Canada deal with it?
Submit your applications for registry to the Association clearly indicating female and “twin to male.” We will date stamp your application*, and return it to you for future resubmission. If and when the female twin is confirmed to be a breeder**, you may resubmit the application to receive the certificated of registry for that animal. A female born twin to a male will not be registered until she is confirmed a breeder.
Is a test available?
A DNA freemartin test is available at a cost of $35. The freemartin test is a predictive test and is not an absolute indicator of the reproductive ability of an animal. While the test may be used as a management tool, the result of the test is no longer accepted for registration.
Freemartin test requests can be noted either on the animal’s application for registry, or by contacting our customer service at 1-855-756-8300 ext. 600. A test kit and corresponding directions will be provided. Test results are reported either positive or negative for the “detection of male DNA” only. The test is not intended or suficient to definitively detect freemartinism or determine sterility
**To avoid late fees, ensure the application is submitted less than three months after birth. The original date stamped submission date will be used to calculate the fees.
**When the female “twin to a male” is confirmed pregnant by your veterinarian or has calved, forward the application for registry to the office along with a statement to this effect.