The best counter argument to the validity of breed-to-kill as 'conservation' operations is that true conservation is about maintaining an entire ecosystem, not just a single species.
To use the example of so called 'big game'; the point of conserving lions is so that the food chain hierarchy stays intact. Without top level predators the whole system often collapses. Breeding lions and releasing them into the wild artificially inflates populations. For this reason, release-to-kill is still irresponsible despite any perceived 'conservation' benefits.
Even if the raising of those lions take's place in captivity it is no more about 'conservation' than farming animals for food (or perhaps even worse, farming animals for the sole purpose of taking pleasure in killing them seems abhorrent, try explaining that to a child. Death, if necessary should be metered with the greatest respect for the being who is sacrificed. Pleasure should in no way be a part of killing).
Additionally,if the raising of lions takes place in the wild, then breeding them in numbers greater than what the ecosystem can support for the sake of being able to 'hunt' them also in no way constitutes 'conservation'.
Pretty much the only way that breeding or killing lions could be considered conservation is if the populations are being actively managed as part of an overall ecosystem stewardship program taking into consideration all aspects of the ecosystem.
The ultimate goal would be to have breeding and culling conducted by state-sponsored wildlife officers, paid a regular wage. In the future, this may be a possibility for Africa but at present it's not even possible in Australia.
We offer rewards for private hunters for the killing of foxes, wild cats and many other introduced animals. If African conservation institutions wish to allow private hunters to assist in population management in the interim, fine, it's a step along the way, but to be breeding, releasing and killing with no regard for the ecosystem as a whole and for no other reason than pleasure, that is just wrong.
Also, any good hunter only shoots when he is sure to kill. Amateurs maiming bred-to-kill animals is disgusting.
Unfortunately though, I don't think bred-to-kill lions are one of Africa's larger problems, Ebola springs to mind, also the premature death of child soldiers is still to much of a concern in parts of Africa.
The only way to solve lower level issues like breed-to-kill programs is to solve the basic needs of humanity living in Africa.
Creating economic prosperity in a sustainable manner so that the majority of African residents receive education and are capable of being the future builders of the governments that will solve problems like that of breed-to-kill programs is the first and foremost cause.
It is about reducing the barriers to obtaining education for all people living in Africa. Reducing these barrier is the only way lions and other 'big game' will stop being bred to kill in the long run.
It is impractical to implement incrimination laws in every country from which hunters originate. Legislation would need to be passed in likely 50+ countries to have any impact and the infrastructure to police that legislation would also need to be implemented.
The only way to save Africa's lions and other 'big game' is to encourage the economic growth of Africa in a sustainable way.
Oh the tyranny of the limited resource allocation decision.