I've had dogs that showed no interest on rats,self entered at 11m old and stayed for 3 hr plus like a seasoned pro.ive also had them go the once and never want it again,pups that have gone to pet homes and come back at 4/5 yr old and given them a few rats they flown to ground.My mate had his dog do nothing for nearly 4 seasons when he got locked up,we were still digging to it at nearly 12yr old.There are no hard and fast rules,it comes down to You to do your best and be able to read the signs,good or bad.Can have the best breeding and be dirt.I personally won't write one of my own off until ov