Hello Tom, 

Thanks for taking the time to write.   I dont know how much help I can be to you.  People around where I live that hunt have basically 3 types of what we call cur dogs.  The blackmouth which is yellow mostly, but some red ones are around, next the brindle cur, and last a mix of one of the above with another breed such as a hound or pit.   I cant remember seeing what we call cur dogs in my part of the woods with half clear and half blue eyes.   Most of the time when I see a dog with eyes like that, I usually also call them a cur figuring they eiether have some catahoula or heeler in them.  

 

  My suggestion would to be to go to the web site http://www.catahoulaleopard.com/bbs/  its a message board for folks who raise catahoulas.  Theres a couple of vets that contribute on there and a man named Don Abney thats done extensive research and written books about catahoulas, possibly someone there could help with the genetics of your dog.

 

  Also, the United Kennel Club aka UKC has a DNA program that could maybe help desipher what make up your dog is.  You should be able to find their web site on most any search engine on the net.

 

Jim