RE: Okay if I neuter my big lab....
Both dogs are nice lookin'.
Getting him clipped will not affect his hunting abilities, and the best way to keep him from straying is to build a kennel run for him. If he has a tendency to put on weight after neutering, then just cut down on the amount of food you are giving him and/or work him more. Obesity is due to the intake of more calories than are expended.
If you are not planning on breeding him (and he is skeletally mature) then getting him clipped is probably a good idea.
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