i have a patterdale, Jack, hes 26 weeks old and had his first rat last week......hes been watchin older dogs working rats, but never seemed interested, went on a local farm last week and he sniffed out a rat from under some old guttering, and chased it but seemed to hesitate when he got close, the rat ran under some wooden pallets and Jack chased it, with some encouragement from me he got it, he got bit on his top lip but managed to shake it to death.....we went out the next day full of excitment, he chased another rat and killed it instantly, he obviously didnt want to get bit again, hes keen