It's a bit weird, but I've seen hundreds of B-westerns and although Hoof and Mouth Disease is NOT a common theme in these films, "Home on the Prairie" is the third one I've seen in the last 10 days!! Yes, aside from this film, Republic made a couple Roy Rogers films with similar plots....."Pals of the Golden West" and "Down Dakota Way"!. What an odd coincidence!
Early on in the film, Belknap finds out that his herd has been infected with Hoof & Mouth. Instead of destroying the cattle, he instead wants to send them to market....no matter that it might end up killing thousands of cattle if he does this. But Gene is a border agent and the guy knows he cannot get the infected cattle past him....so he and his henchmen plan on discrediting Gene to get him off the job. Then, moving these infected animals should be much easier.
In general, this is about average for a Gene Autry film. The strange thing about it is that Gene and Frog didn't sing much at all in this one!