DNA quirk that could lead to our oldest horse breed dying out
FOR hundreds of years, the Suffolk Punch horse has been used by farmers to till fields across the country.
But now Britain’s oldest native breed is teetering on the brink of extinction, because not enough females are being reared.
Fearing that a mystery male gene is undermining efforts to save the breed, conservationists have called in a leading geneticist, who they hope will resolve the fertility crisis. Their latest gambit comes amid ongoing efforts by landowners to increase the existing pool of breeding mares.
However, the current conservation drive is being thwarted by the unusually high number of male foals reared in recent years, with the number of eligible mares falling by 45 per cent in 2017.
According to recent figures published by the Rare Breeds Survival Trust, just 33 fillies were born between 2014 and 2016 – nearly half the number of males reared during the same period.
While the cause of the gender imbalance remains unclear, Dr Sarah Blott, a leading geneticist at the University of Nottingham, told The Daily Telegraph that conservationists might now have to consider artificial insemination techniques in order to ensure the breed’s survival.
Dr Blott, who has been tasked with sampling DNA from Suffolk Punch horses in order to determine whether an underlying fertility crisis is blighting breeding efforts, said that the numbers showed a “clear swing” towards males.
“The numbers are low to begin with, they are very rare,” she continued. “The stallion determines the sex of the offspring because the sperm are either X- or Y-bearing. I’ve never come across a disease in horses where the sex ratio of sperm has been distorted.
“But in cattle they use something called ‘sex semen’ to control this. Cattle producers can separate sperm and use it to get more females. If you wanted to produce more females, that may be the only option. They may have to start to use these technologies... but [it] becomes expensive.”
Echoing Dr Blott’s comments, Nigel Oakley, a Suffolk Punch breeder, said that certain stallions with the “propensity” to produce male offspring might have to be “held back” so that others with a track record of producing females have more opportunity.
“These numbers do not bode well for the breed – this is our heritage,” he added. “Once they are lost they are gone forever and our grandchildren’s children may never see them.
“Hopefully it won’t be long before we can develop further to breed more stallions and mares all over the country.”