Honestly...NOTHING...It is a registery thing..AKC wanted to get away from the shorty JRs so they started calling them Parsons..If you do want a TRUE Jack Russell, get a JRTCA (Jack Russell Terrier Club of America) registerable dog. JRTCA is out to keep the breed true to what Rev. John Russell started. Alot of the AKC dogs were JRTCA dogs at one point, but due to certain circumstances they were either kicked out of the club or changed to AKC because of their opinions.
Answered by karispups - 4/9/2013 1:51:49 AM