Get a Catch alive trap and take it down near you local tip or farm get one in straight away let u pup see it and get keen with it nock the rat your self and then give it him to chomp and get taste do that a thew time then when you think he’s ready it’s down to u to give it him and should smash it once he’s had a few nips it will know who’s to chomp them and my advice if you don’t like digging don’t get it going on rabbit