PLOS ONE: Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers
"Of early-neutered males, 10 percent were diagnosed with HD, double the occurrence in intact males. There were no cases of CCL diagnosed in intact males or females, but in early-neutered males and females the occurrences were 5 percent and 8 percent, respectively. Almost 10 percent of early-neutered males were diagnosed with LSA, 3 times more than intact males. The percentage of HSA cases in late-neutered females (about 8 percent) was 4 times more than intact and early-neutered females. There were no cases of MCT in intact females, but the occurrence was nearly 6 percent in late-neutered females. The results have health implications for Golden Retriever companion and service dogs, and for oncologists using dogs as models of cancers that occur in humans." - hip dysplasia (HD), cranial cruciate ligament tear (CCL), lymphosarcoma (LSA), hemangiosarcoma (HSA), mast cell tumor (MCT).
"For all five diseases analyzed in the present study, the disease rates in males and/or females were significantly increased when neutering was performed early and/or late."
Even more concerning - However, the possibility that age-related cognitive decline could be accelerated by neutering should be noted . "Sexually intact male dogs were significantly less likely than neutered dogs to progress from mild impairment (ie, impairment in 1 category) to severe impairment (ie, impairment in ≥ 2 categories) during the time between the first and second interviews. This difference was not attributable to differences in ages of the dogs, duration of follow-up, or the owners, perceptions of the dogs, overall health."
I do hope that one day we can recommend desexing only where appropriate and for legitimate, proven effects. I find it very disturbing at the moment that people are told to desex their pets for health reasons by their vets when so far, every scientific study suggests otherwise.