A small electric fence can do wonders to a dog's sensitivity of where to
go and where not to, even when you remove it later, they still wont go
there. If they cant see what bit them, they stay clear.

kanghuaiqiang wrote:
Dog fence
A dog fence can become rather expensive venture, so leave the idea of
fencing your entire premises and start by erecting a small dog fence
even though your yard sprawls over a larger area.
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