A study led by DeForge et al. (2024) in the Journal of the American Veterinary Medical Association provides compelling evidence that early neutering (before 12 months of age) increases the risk of cruciate ligament rupture (CR) in Labrador Retrievers, a breed already genetically predisposed to the condition.
Researchers examined 93 genetically discordant Labradors—dogs whose clinical symptoms did not align with their predicted genetic risk. Of these, 58 were CR cases and 35 were controls. Environmental variables such as neuter status, age at neutering, weight, BMI, and athletic activity were analyzed alongside genetic data.
The results identified age of neutering as the sole significant environmental risk factor. Specifically, dogs neutered before 12 months were more likely to develop CR, regardless of sex or athletic status. Body weight and athletic activity were not associated with CR in this discordant population.
The study emphasizes that while the primary driver of CR in Labradors remains polygenic intrinsic risk, neutering age is a critical modifiable factor. These findings can help guide veterinarians and breeders in managing orthopedic health, advocating for delayed neutering in genetically at-risk dogs.
Source: T.L. DeForge, M. Momen, G. Conidi, P. Muir, and S.J. Sample, Journal of the American Veterinary Medical Association, October 9, 2024.