Farming rare animal species will not halt the illegal trade in animal parts, a conservation group has warned.
Care for the Wild says the fact that the animals are worth more dead than alive is hampering efforts to save species such as tigers and rhinos.
They add that selling parts from captive-bred creatures would not result in a halt of illegally traded animal parts and would instead fuel demand.
A kilo of powdered rhino horn can fetch £22,000 on the black market.
Mark Jones, programmes director of Care for the Wild International, said recent media reports suggested that the South African government was considering "a feasibility study on some kind of farming or ranching of rhinos for their horns".
"This flagged up that these sort of farming initiatives are still being considered at quite high levels," he explained.
"Rhinos are in quite a lot of trouble at the moment, with the value of their horns going through the roof, especially in Vietnam."
Media coverage in 2009 reported that a member of the Vietnamese government said he took rhino horn and his cancer went into remission, prompting a growth in the demand for the illegal product.
"The sums that are being paid for powdered rhino horn are just astronomical."
There are two species of rhino found in Africa. While the white rhino (Ceratotherium simum) has enjoyed a surge in numbers in recent years, taking the population to about 17,500, it is a very different story for the northern sub-species Ceratotherium simum cottoni.
It is listed as Critically Endangered, and conservationists have warned that it is on the "brink of extinction" with four or fewer individuals remaining.
More than 200 rhinos have been killed in South Africa for their horns since the beginning of this year. This week, the nation's defence minister told BBC News that troops would be deployed to help rangers fight poachers.
Horn of hope
Mr Jones added: "One of the issues we have is that the white rhino population (not sub-species) in South Africa/Swaziland is on Appendix II of Cites, which means some export is allowable.
"Also, China has been buying quite large numbers of live rhinos from South Africa in recent times, and there is concern that some people within China may be setting up rhino horn harvesting.
"An awful lot of people from Vietnam, in particular, seem to be coming over to shoot rhinos and take the horns home as trophies.
"Yet, they don't seem to have much interest or history in hunting but appear to have an awful lot of history in getting the horn out of the country."
The Convention on the International Trade in Endangered Species of Wild Fauna and Flora (Cites) is a global framework designed to regulate the global commercial sale of wild species.
If a species is listed as Appendix I, such as tigers, this means that no commercial exports are permitted. However, Cites has no jurisdiction within national borders.
The idea of farming threatened species, through captive breeding programmes, is not new. Bear bile farms have been in operation in East Asia for three decades.
The practice involves caged bears being fitted with tubes that allows the bile from the animals' stomachs to be extracted and legally sold.
"Putting the welfare issues of the practice to one side, there is absolutely no evidence coming out of China that Asiatic black bear (Ursus thibetanus) populations are stabilising or increasing," Mr Jones told BBC News.
"Another example is turtle farming, which is arguably a multi-billion dollar industry. Populations of freshwater turtles in China and beyond continue to decline.
"Even the supply of very, very large numbers of turtles from the farms does not seem to be having any positive impact on the conservation of wild populations."
Probably the most controversial topic involves farming tigers. Campaigners suggest that for every one of the estimated 3,500 wild tiger alive in the world today, there may be three farmed tigers in China.
China banned the trade in tiger bones and products in 1993, but wildlife monitoring groups say that has not stopped the practice.
A recent report by Traffic estimated that 1,000 of the big cats were illegally killed in the past decade to meet the demand for tiger parts.
In an effort to protect the world's remaining wild population, a tiger summit begins on Sunday in St Petersburg, Russia, with the aim of drawing up a road map to ensure the species is not wiped off the face of the Earth.
Campaigners are not hopeful that Chinese representatives will engage with other delegates on the topic of tiger farms.
Farming rare species, it is argued, could help protect dwindling populations because it would meet the demand for parts of threatened species without the need to kill wild individuals.
"On the face of it, it does seem like a logical argument," said Mr Jones.
"But for many people, there is a perception that products from wild animals is better than that from farmed or ranched animals, or animals that are kept in captivity."
As a result, increasingly affluent people are willing to pay a premium for products from wild-caught specimens.
He explained that there was no simple answer to ending the illegal hunting of threatened wild animals, especially when the species commanded a high value.
"It is complex, but we are talking about the establishment of good legal provisions to protect species in their home range countries, and the adequate enforcement of those laws," Mr Jones observed.
"You also have to consider education programmes to inform the public of the illegality of poaching these animals, but also the value of the live animals to the ecosystem in which they live.
"If you remove a species from a particular ecosystem, then the system changes and usually diminishes."