From what I have read and on the previous threads here which quote scientific research, leave it til they are older. There are more cases of cruciate and other ligament problems in neutered puppies due to its effects on the leg bone growth plates. Also, if left to mature longer he will develop the love kelt broad male head and neck,
Bob now 8 years old. isn't neutered, no humping problems, no entire bitches for miles, and is very friendly with all dogs and has never been aggressive with any. Human perverts ought to be castrated though!
The literature on prostate cancer is also debatable. Personally I have never come across it in anyone's pet. other debilitating conditions like Cushings, Addisons, pancreatitis, auto immune diseases etc see far more common.
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