One debuted in 1961 under his own title for fifteen issues plus several backup tales in other magazines and a crossover with another hero, the other appeared in 1965 then resurfaced four more times in the silver age. Yep, Jaguar was far more successful, probably because Archie Comics was fishing for the next new hero. Animal Man was simply another character created to fill a series losing readership at DC Comics.
These two, while remarkably similar in adopting powers of animals thanks to exposure to energy from out-of-this-world. Yet A-Man's limitation of needing to be near an animal to keep his power meant his tales were one-note and limited the credibility of his access to such abilities. Jaguar, on the other hand, had limitless potential, except that his publisher mainly focused on teen comics not heroes.