How to handle a dog quit hunting?

all good points so far...the very best dog I have owned changed on me when he was about 7 years old...back in those days quite a few of the places I hunted the hogs moved through and weren't always there...and him having a few old battle scars I think he just changed his strategy...it took me a few hunts to figure what was going on with him...when I cut the dogs loose he would make a quick loop and if he showed back up in less than 10 minutes or so you could bet you bottom dollar there were no hogs in the area...in the mean time the other dogs were out hunting...a mile on down if he rolled out it meant he could catch a scent of hog and he would roll out...in a while you would hear him baying a hog...9 times out of ten he struck first and he was a fairly cold nosed dog...

it is possible your dog could be doing the same...

I know when roading dogs if they get interested in some hog scent and we keep moving sometimes the dogs will learn pass up tracks if they aren't hot enough if we just keep moving along...I will wait until they either strike or give it up before I move again...this causes some dogs to only take the hotter tracks...this can be an issue especially if the places are big and the hogs few...