In Sudan’s death, lessons on how humans aid extinction of species

The race to save the northern white rhino from extinction has intensified following the death of Sudan, the last surviving male after months of ill health at Ol Pejeta Conservancy in Laikipia County.

The hope of species’ future generations now rests on researchers making breakthroughs in technology and ability of the surviving females to yield eggs to be carried by a surrogate southern white rhino.

The conservancy’s management said Sudan’s remains would be preserved for future generations but the method was yet to be decided.

FEMALES

“Sudan died on Monday and consultations will be made before a final decision on how to preserve the remains. Definitely, he will not be buried like the others since the remains is of great interest to conservationists and scientists,” said head of conservation at Ol Pejeta Samuel Mutisya.

The  hope of preventing the northern white rhino from disappearing from the face of the earth hinges on a delicate scientific process that has never been tried before. 

Attention now turns to the only remaining females, Najin and her daughter Fatu who are also confined at Ol Pejeta Conservancy under a 24-hour surveillance by armed guards.

According to the veterinary officer in charge of the conservancy Dr Stephen Ngulu who was taking care of Sudan,  the two female species will donate eggs (ova) which will be fertilised by an already stored sperm from Sudan and the offspring will be planted in the womb of a surrogate mother - a southern white rhino at Ol Pejeta Conservancy. The process is yet to begin and there are no timelines.

However, one female southern white rhino, Tauwa, 19, has been identified to be the surrogate mother and has been a close companion of Najin and Fatu for five years.

$9M TARGET

“She has been separated from male members of her species in preparation for In Vitro Fertilisation (IVF) procedure (where fertilisation is done by manually combining an egg and sperm in a laboratory dish to form an embryo, which is then transferred to the uterus). If all goes well, her first pregnancy will be of a northern white rhino,” said Mr Jacob Anampiu, a ranger at Ol Pejeta who together with nine others have been taking care of Sudan.

The 45-year-old rhino was being treated for age-related complications, muscular and bone wastage combined with extensive skin wounds, the Ol Pejeta Conservancy said on its Twitter handle.

Threat facing the species came to the fore last year when the conservancy enrolled Sudan on Tinder, a dating app, in a bid to raise money for a northern white rhino breeding campaign.

We could, however, not ascertain how much of the $9 million (Sh900 million) target had been raised by the time of the animal’s death. The money was intended to help develop reproductive technologies for the species, including IVF.

The Conservancy said Sudan’s genetic material which was collected yesterday “provides a hope for future attempts at reproduction of northern white rhinos through advanced technologies.” In 2014, Sudan’s first sperm cells were collected and stored in banks in Europe and Kenya.

EGGS

Researchers cite IVF as the most promising means of  conception since, like Sudan, the two surviving female rhinos are unable to breed naturally. Female rhinos start breeding from age six or seven.

“When we performed a reproductive assessment on the two animals, we realised that they both had compromised uteri such that conception cannot occur,” said Dr Ngulu during an interview with the Daily Nation last year.

“We also discovered that the older female has weak hind legs, further compromising her chances of carrying a pregnancy (which lasts 17 months) to term,” he added.

In May last year, Dr Ngulu said: “As we speak, we do not have any northern white rhino female eggs. That means that our eyes and focus are on these two females, because should anything happen to them all our efforts will have been wasted.”

If the IVF procedures are successful, they will allow researchers to reintroduce the species back into the wild. It could also help scientists explore ways of bringing back other animals facing extinction. But for IVF to be performed, female  egg cells have to be collected from the animals, a scientific procedure not tried on rhinos to date.

AI

“Since the procedures for collecting these eggs are not known, everything we are doing now is experimental,” Dr Ngulu said.

Scientists in Germany, the US and South Africa have been trying to perfect a procedure known as ovum pick-up, which involves collecting eggs and maturing them in a laboratory.

The ovum pick-up, however, is expensive and requires an intricate procedure that requires meticulous techniques to ensure the animal is not injured.

“You cannot afford to go wrong when you only have two surviving animals in the whole world,” said Dr Ngulu adding “You need to perfect it before you attempt it.”

Besides IVF, scientists are also exploring the possibility of growing reproductive cells from stem cells, which have the potential to develop into many different types of cells in the body.

Artificial Insemination has been discounted because it would end up using bigger volumes of sperm cells just to reproduce one embryo. With IVF, only one sperm cell is needed to fertilise an egg.

SUNI

Sudan was brought from Czech Republic to Kenya in 2009.

He, his daughter Najin, 28 and granddaughter, Fatu were the only three living northern white rhinoceroses  in the world. They lived at the Ol Pejeta Conservancy in Laikipia, Kenya, surrounded by armed guards to protect them from poachers.

Another male, Suni, who died in 2014, and two other females were brought with him in an effort to see if they could reproduce in a wild habitat.  They were put on a special diet with the cost of maintaining one estimated at Sh6million annually. Mr Anampiu said Sudan was being fed on carrots, bananas, apples, pellets and Lucerne for breakfast in an effort to keep him healthy. However, despite the animals mating none of the two females conceived.

“Up until two weeks ago, we thought we could give him palliative care but after extensive consultation, the decision to let him rest was made,” said Dr Stephen Ngulu, the conservancy’s veterinarian yesterday. The team included specialists from the Dr Králové Zoo in Czech Republic,and the Kenya Wildlife Service. The decision to euthanise him was informed by the fact that he could not stand or eat and was in constant pain.