Daily News Archive
Daily News Subscription
Research Shows Mare's Condition Impacts Sex Of Foal
A study of wild horses in New Zealand "has found that broodmares that are healthiest at the time of conception are more likely to have colts," reported thehorse.com. The study (by researchers Elissa Cameron MSc PhD & Wayne Linklater PhD) "found a striking correlation between the change in a mare's condition & the sex of her foal". In mares that were gaining weight at the time of conception, 80% had a colt, while only 3% who were losing weight gave birth to a colt. The researchers hypothesise the reason "is that strong mares will produce strong foals & a strong colt would be able to spread the mare's bloodlines more than a strong filly". Cameron said she believes it is "the change in the mother's condition that might determine the sex of the foal", but at present the mechanism "that might be causing this relationship isn't understood". Cameron noted: "It appears that glucose may play a role, as we manipulated glucose levels in mice & got a shift in sex ratio. However the relationship is complicated, especially if it is driven by glucose levels, since glucose is pretty well regulated by insulin."