My main pig dog for a few years was a strong eyed bitch given to me by a mate when she was five. Dream would work sheep and cattle for him. He would muster goats in the weekends with her and if he saw any fresh pig sign he would go back in the evening. When she had the tracking collar on her and he had the 44 she wouldn't touch a goat. When mustering goats she wouldn't catch a pig. A really smart finder on pigs and a hard stopper. Everything comes down to the intelligence of the dog and the handler and then just consistency and repetition.
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