Twins in horses is something that occasionally occurs, 20% in Thoroughbreds. But due to the poor prognosis of survival of either one or both, vet intervention at days 16-20 of the pregnancy is recommended.
In the cases where the mare is not scanned post breeding or in the rare cases when she is scanned, but one embryo is hiding, twins can occur. In these cases there is a high probability (80%) that the mare will absorb/abort one or both pregnancies. But when this does not happen, they both go to term, and there can be an extra surprise waiting for owners!
In the case of these two, the mare’s owner didn’t know the mare had been bred (cheeky neighbours stallion) and so the mare wasn’t scanned and out popped twins. Luckily for these two the mare is an experienced mother and accepted both foals (rare occurrence, as mares are often confused by having two).
Both these colt foals were born with deviations in their legs, but are slowly strengthening up, and are restricted to a small flat paddock, as with twins you treat them as if they were born premature. So their bones are softer than normal and while they are strengthening up they are at risk for abnormal changes (collapse of bone around joints).
While this is a heart-warming success story, we highly recommend a pregnancy scan at 16-20 days, preferably 16 days. If twins are detected during this window the vet can usually “squish” one of the embryos, while leaving the remaining embryo to continue on to full term.