Researchers determine sex of unborn foals with new test
It is possible to find out the sex of unborn foals from as little as eight weeks after conception by testing mares’ blood plasma, researchers have found.
An Iranian team from Shahrekord University was able to determine the sex with a good rate of accuracy using a new technique.
The researchers developed a test used to detect circulating cell-free foetal DNA (ccfDNA) within the plasma of pregnant Arab mares.
They then identified the SRY gene, which is responsible for the initiation of male sex determination, within the DNA.
This information was used to predict the sex of the foetus.
Peripheral blood samples were collected from each mare used in the study, on a single occasion, between eight and 20 weeks after conception. The researchers extracted the ccfDNA from 3ml of maternal plasma, using the new test to detect the SRY gene.
Results for the gene were inconclusive from the first round of testing, researcher Ali Kadivar and his colleagues stated in their study, which has been published in the Journal of Equine Veterinary Science online.
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But conclusive results were obtained from a second round of testing, they said, from which the group was able correctly to predict the sex of 22 of the 25 unborn foals, an accuracy rate of 88 per cent.
The group wrote: “To conclude, SRY gene can permit detection of equine fetal sex with a good accuracy by analysing cffDNA in maternal plasma just after 8 weeks of gestation.”
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Mr Kadivar’s colleagues for the research were Rohollah Dehghani Tafti, Heidar Heidari Khoei, Mahboobeh Heidari Nasirabadi, Naser Shams Esfandabadi and Narjes Cheraghi.
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Eleanor is an experienced journalist who spent over eight years working for local and national newspapers before joining H&H as news editor in March 2016. Passionate about equine welfare and exposing the truth, Eleanor has reported on all aspects of the industry, from Brexit to anti-bullying campaigns, and from dressage rules to mules. Her sport of choice is showjumping, in which she competes her own horses, and she also enjoys reporting at local jumping shows through to international championships.