Lions to give birth to tigers

Scientists battling to save endangered species are turning to surrogates from other species for help, according to a report in the Sunday Times yesterday. A team of researchers at the Audubon Institute, University of New Orleans has frozen 170 tiger embryos produced by IVF (in vitro fertilisation), which they plan to implant into lionesses within the next eight weeks.  

The team, headed by Professor Betty Dresser, carried out the first successful inter-species transfer of a frozen IVF embryo when they used a domestic cat as a surrogate for an African wildcat. They have also frozen embryos from nearly 40 other species - including antelope - ready for implantation. For the tiger embryo transfers, the scientists will test two different sizes of embryos - 600 cells and several thousand cells - to see which works best.

If the procedure is successful, the baby tigers will stay with their surrogate mothers until they are weaned, after which the scientists hope to release them into the wild. 'In the inter-species transfers we have done so far the mothers have raised them as their own' said Professor Dresser. 'They may think they have an ugly-looking baby, but it smells like them and they know they have given birth to it, so it must be theirs' she added.