"Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers"

This study analyzed the potential impacts that spaying or neutering* Golden Retrievers had on the following joint disorders and cancers: hip dysplasia (HD), cranial cruciate ligament tear (CCL), lymphosarcoma (LSA), hemangiosarcoma (HSA), and mast cell tumor (MCT). Records of 759 dogs aged 1 to 9 from the Veterinary Medical Teaching Hospital at UC Davis were used in the dataset. The Golden Retrievers were classified by gender, as well as early neutered (defined as neutered at less than 12 months of age), late neutered (defined as neutered at greater than 12 months of age), and intact.

 

Joint Disorders:

It was found that early-neutered males had double the percent incidence of hip dysplasia as intact males and early neutered males also had a greater percent incidence than late neutered males. There was no significant difference between the categories in females with hip dysplasia.

There were no cases of cranial cruciate ligament tear in intact males, intact females, or late-neutered females.  However, with early-neutered dogs, 5.1% of males and 7.7% of females had CCL, which indicates a significant increase from late-neutered and intact dogs.

The researchers compared the body condition score (BCS), or a score of the weight on the joints, of early-neutered dogs diagnosed with the joint disorders and without the joint disorders. This was done in order to rule out the possibility that the neutered Golden Retrievers who had a disorder had a greater chance of getting it because they had more weight on their joints than those without the disorder. This comparison indicated that there was no significant difference in the BCS. 

 

Cancers:

Lymphosarcoma occurred almost three times more frequently in early-neutered males than in intact males and there were no cases in late-neutered males. There was no significant difference for females.

Late neutered females had hermangiosarcoma over four times more than in intact females and early neutered females. There were no significant differences in males.

There was no occurrence of intact females having mast cell tumor, whereas 2.3% of early-neutered females and 5.7% of late-neutered females were diagnosed. There was no differences in mast cell tumor for males.

Figure 1.  Percentages and number of cases over the total sample size for each neutering status group; intact and neutered early or late for male Golden Retrievers (1–8 years old) diagnosed with hip dysplasia (HD), cranial cruciate ligament tear (CCL), lymphosarcoma (LSA), hemangiosarcoma (HSA), and/or mast cell tumor (MCT) at the Veterinary Medical Teaching Hospital of the University of California, Davis, from 2000–2009.

Figure 2.  Percentages and number of cases over the total sample size for each neutering status group; intact and neutered early or late for female Golden Retrievers (1–8 years old) diagnosed with hip dysplasia (HD), cranial cruciate ligament tear (CCL), lymphosarcoma (LSA), hemangiosarcoma (HSA), and/or mast cell tumor (MCT) at the Veterinary Medical Teaching Hospital of the University of California, Davis, from 2000–2009.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

*In the study, both spayed and neutered was referred to as neutered.

Torres de la Riva, G., Hart, B., Farver, T., Oberbauer, A., Messam, L., Willits, N., and Hart, L., 2013, Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers. PLoS ONE. 8:e55937

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0055937#pone-0055937-g002