Saving rhinos with IVF

A UK zoo is taking part in a radical plan to save the world's last three northern white rhinos from extinction. At Longleat safari park, scientists have collected eggs from southern white rhinos - a closely related sub species - to use for IVF. The eggs will help researchers to develop the technology to help the remaining northern whites to reproduce.

A back-up plan is to mix eggs from the southern white rhinos with sperm from northern whites to create a hybrid. It means that if the bid to produce a pure northern white rhino fails, at least some of the critically endangered animal's genes will live on. Darren Beasley, head of animal operations at Longleat, added: "Effectively the female rhinos would act as IVF mothers, with embryos partly derived from northern white male sperm.

Experimental fertility technology may be the last hope for northern white rhinos. The animals were once found across central Africa, but illegal poaching, fuelled by the demand for rhino horn, wiped out the wild population. Today, there are just three of the animals left: a male, who is over 40, and two younger females. The former zoo animals, which are inter-related, are kept under tight security at Ol Pejeta Conservancy in Kenya. However, a combination of age and fertility problems means that none is able to breed.

The rhinos have not mated naturally with the zoo's male, which is why they were put forward to take part in the study. Extracting the eggs required millimetre precision. Prof Hildebrand said: "We have a two-tonne animal, and the ovaries are more than two metres inside. We operate on an ovary that is lying next to a blood vessel and if we poke that with our needle, there is a very high risk that the animal dies. We have developed a very sophisticated technique to make sure we don't do any harm to the animals."

The eggs have now been rushed back to the Avantea clinic in Italy, a lab that specialises in assisted reproduction in animals, where they will be prepared for fertilisation.

The fertility scientists admit the chances of success may be slim - but they are optimistic that the technology could help. Prof Hildebrandt said: "The classical conservationists would not even call this a conservation approach, because it is so technical, so far beyond what you normally do. But we hope future generations will understand that this is the way to go. It is a technology that allows us to bring a species back form the brink of extinction that would normally be impossible - and that is our goal. We are extremely optimistic that we will achieve that."
http://www.bbc.com/news/science-environment-40655273