Apologies, I let the title ("injecting") mislead me. I assume it's a multitude of factors: - poachers/smugglers would need to know about this before they get c

Apologies, I let the title ("injecting") mislead me. I assume it's a multitude of factors: - poachers/smugglers would need to know about this before they get caught (doesn't save that rhino, but adds friction to smuggling and removes some smugglers/buyers - both the ones caught and the ones who quit because they're worried about it) - testing for it likely requires non-trivial equipment (again adds friction to the trade) - depending on how visible the hole is, accurately locating it inside the horn may not be trivial either - once located, removing it still devalues the horn