Harare - Is it painful for a rhino to be dehorned?No, says a wildlife vet who's involved in an ambitious dehorning exercise in Zimbabwe. "It's like having your nails filed," says Lisa Marabini of the AWARE Trust."As long as you don't cut into the horn bed it is not painful for the animal," she told News24 in an interview.Zimbabwe is in the process of dehorning all rhinos living in the country's national parks, she added.That doesn't necessarily mean all of Zimbabwe's estimated 700-800 black and white rhinos (since some live in private conservancies) but it does mean a significant number. AWARE has just finished dehorning roughly half of them.Like South Africa and other countries in the region, Zimbabwe is ramping up its battle against rhino poachers who target these beautiful creatures for their horn, which is highly prized in Asian medicine.Heavy-duty tool Last year poachers killed 50 rhinos in Zimbabwe.Of course, says Marabini, you can't use a simple nail file to dehorn a rhino: in fact, the horn has to be cut off with a much more heavy-duty tool."The keratin in rhino horn is much more densely packed than in finger nails so it has to be cut with a chainsaw," she said.The rhino's horn bed - where there are nerves and blood vessels just as there are in a human nail bed - is left well alone.The operation is done under anaesthetic, which obviously carries its own risk "but every precaution is taken to minimise the risk," she said.This level of care comes at a significant cost: Marabini puts it at between $800 and $1 200 US per rhino. The operation is most expensive when vets and conservationists are working in very bushy terrain. In those conditions, Marabini says they need "a fixed wing aircraft with a spotter to keep an eye on the rhino, as well as a helicopter to dart from." Significant protective effect Dehorning rhinos to put off poachers is not a new step in Zimbabwe: it has been happening since the early 1990s here.It was one of a cocktail of measures introduced as poaching took an enormous toll on what had been a thriving population of rhinos in Zimbabwe. Government estimates from the mid-1980s put the figure of black rhinos alone in Zimbabwe at as many as 3 000, although at least one expert has suggested the total was more likely around 2,000. The total number of black rhinos in Zimbabwe dipped to as low as 300, though it has climbed since then.While dehorning rhinos has had a significant protective effect on populations in parts of the region, other anti-poaching methods may be considered particularly when conservationists are trying to protect large numbers of rhinos living in large areas. Drones are one such method.Zimbabwe has recently acquired drones to help fight elephant poaching in the west of the country, it was reported last month.