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rhino embryos Archives - Rhino Review

San Diego Zoo researchers retrieve rhino’s eggs to recover critically endangered species

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Karla Rendon-Alvarez, NBC San Diego | March 11, 2020

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Researchers at the San Diego Zoo Safari Park collected a female southern white rhinoceros’ eggs as a step to genetically recover the northern white rhino.

Original photo as published by NBC San Diego.

On March 6, a team of more than 30 veterinarians, wildlife care specialists and researchers from the San Diego Zoo Global and Embryo Plus South Africa teamed up to perform an ovum pick-up on 9-year-old rhino, Nikita. The non-surgical procedure gathers a live animal’s eggs and is modeled after a similar method used on horses and cows.

Nikita the rhino was under anesthesia during the procedure as researchers located her ovaries by ultrasound. The animal’s eggs were then retrieved by a tiny needle that was inserted into each follicle. Those eggs are expected to mature in vitro and fertilize by intracytoplasmic sperm injection.

Scientific breakthrough marks pioneer cheetah births through IVF, shines light on ongoing IVF on rhinos in Kenya

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Caroline Chebet, Standard Media | March 6, 2020

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Scientists and researchers have recorded a breakthrough following a successful birth of two cheetah cubs by a surrogate mother through In Vitro Fertilisation (IVF).

The first-ever scientific reproduction of cheetahs happened at a Columbian zoo, a breakthrough marked after more than 15 years of research.

According to a statement released by the Colombus Zoo and Aquarium, the achievement could ensure survival of cheetahs in their native ranges in Africa.

“These two cubs may be tiny, but they represent a huge accomplishment, with expert biologists and zoologists working together to create this scientific marvel,” the zoo said in a statement.

Original photo as published by Standard Media: A female cheetah and her seven cubs roam the savanna of Maasai Mara National Park in Southern Kenya. [Reuters]

Conservation scientists, the zoo said, have been doing researches to boost the number of cheetahs which, according to the International Union of Conservation and Nature, are listed as vulnerable with decreasing population trend in their native ranges. The two cubs were born on February 19.

The procedure to birthing the two cubs involved fertilisation of sperm and eggs in a laboratory and then incubated to create embryos. The embryos were implanted into the surrogate mother’s womb, where they developed into foetuses.

The breakthrough on the scientific reproductive techniques on cheetahs come in the wake of the assisted reproduction techniques being tried on the critically endangered northern white rhinos in Kenya.

On scientific milestones to assist in reproduction of northern white rhino, three embryos have been created successfully to be implanted on a surrogate mother at Ol Pejeta conservancy in Laikipia.

The ground-breaking of procedure on the northern white rhinos was marked in 2019 when a team of scientists and conservationists successfully harvested the eggs from the two remaining female, artificially inseminated them using frozen sperm from deceased males and created three viable northern white rhino embryos.

Last January the scientists noted that there was a significant increase in the chances of successfully producing offspring. The procedure also proved to be safe and reproducible, and can be performed on a regular basis before the animals become too old.

Currently, there are plans to select a group of female southern white rhinos at Ol Pejeta Conservancy, which could serve as surrogate mother for the northern white rhino embryo.

This is also expected to be a success, with the first attempt set to be crucial since it has never been achieved before. It is expected that implantation will be undertaken any time this year.

And while the incorporation of scientific technologies in conservation has been on the rise, the breakthroughs shine light in race against extinction.

Scientists estimate that the cheetah population has declined to approximately 7,500.

 

Edward the baby rhino meets herd for 1st time (California)

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Fox 5 | October 10, 2019

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SAN DIEGO: The San Diego Zoo Safari Park’s youngest southern white rhino began integrating with the rest of the park’s rhino herd Wednesday, meeting a rhino other than his mother for the first time since his birth 10 weeks ago.

Edward and his mother, Victoria, have remained sequestered from the rest of the herd since his birth in July to allow the two to bond and ensure he builds weight and stamina. The calf’s weight has nearly quadrupled since then and he has only entered the Safari Park’s rhino enclosure with Victoria.

Edward met Helene, an adult female southern white rhino, after she sparred with Victoria, who was very protective of her calf, according to the zoo’s animal care staff. They will continue introducing him to the rest of the Safari Park’s crash of rhinos as he gets larger and older.

“While Victoria knows the other rhinos, Edward has only observed them from a distance,” Safari Park Lead Keeper Jonnie Capiro said. “It’s time to get Edward acclimated to his crash. We chose to have Helene meet him first, as she is closely bonded with Victoria.”

Edward is the 99th southern white rhino calf born at the Safari Park and the first such calf to be born through artificial insemination in North America. His birth represents a step toward the zoo’s longer-term goal of recovering the northern white rhino, a distant relative of the southern white rhino. Only two northern white rhinos still exist on the planet and both are female.

Zoo officials plan to use stem cells and preserved northern white rhino cells to birth a northern white rhino calf within 10-20 years. The zoo’s southern white rhinos would serve as surrogates for the northern white rhino embryos through artificial insemination, in-vitro fertilization or an embryo transfer.

If the plan proves successful, researchers could attempt similar assisted reproduction techniques with the critically endangered Sumatran and Javan rhinos.

The Safari Park is expecting a second southern white rhino birth early next month. The zoo announced that calf’s conception through artificial insemination last year.

Strides in assisted reproductive techniques for rhinoceros: What do they signify?

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The International Rhino Foundation Blog | September 13, 2019

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There is no easy answer for ensuring the survival of critically endangered rhinoceros species. The International Rhino Foundation (IRF) believes we need to maximize options and minimize regrets, tackling the myriad of challenges facing rhinos using multi-faceted approaches. Some will fail, but some will succeed.

Beginning in mid-August, media across the world reported that an international team of reproductive scientists, including from Berlin’s Leibniz Institute for Zoo and Wildlife Research (IZW) recovered five eggs each from both remaining female northern white rhinos, Ceratotherium simum cottoni, at Ol Pejeta Conservancy in Kenya. The two females have reproductive tract issues which prevent them from carrying a pregnancy to term. Working in concert with Avantea, an Italian laboratory, the team matured seven of the eggs in vitro (in a culture dish). The eggs were then injected with frozen-thawed sperm from two deceased northern white rhino bulls.

Original photo as published by The International Rhino Foundation.

Earlier this week, the team revealed that two of the eggs grew to early stage embryos. This is a phenomenal achievement – the embryos have been frozen and later will be implanted into a southern white rhino (Ceratotherium simum simum) surrogate. Other partners include the Kenya Wildlife Service and. Dvur Králové Zoo in the Czech Republic.

We follow these developments with great interest, knowing that there is a long road ahead before these methods are readily reproduceable. In the words of Dr. Terri Roth, Director the Cincinnati Zoo & Botanical Garden’s Center for Conservation & Research of Endangered Wildlife (CREW) and IRF Vice President for Asia, “It’s a long path from developing a berry-like cluster of cells in a Petri dish to having a herd of healthy rhinos on the ground.”

The work with northern white rhinos has proceeded in a lengthy, stepwise process. Last year, in a paper published in Nature, IZW’s Dr. Thomas Hildebrandt and colleagues described successfully recovering southern white rhino eggs, maturing and fertilizing them with northern white rhino sperm, and successfully developing them to the blastocyst (early embryo) stage in vitro (in a culture dish).

The team also established embryonic stem cell lines from the blastocysts, which were later frozen. (A stem cell is a cell that has the potential to develop into many different cell types in the body during early life and growth.) Conservation geneticists at the San Diego Zoo’s Institute for Conservation Research in collaboration with the Center for Regenerative Medicine at the Scripps Research Institute also are carrying out groundbreaking research, recently turning rhino stem cells into beating cardiac tissue.

The IRF applauds the efforts of all of our colleagues working on Assisted Reproductive Technology (ART) and conservation genetics for rhinos. We also wish to note the importance of keeping these recent accomplishments in perspective, particularly for a subspecies that is functionally extinct. Attempting to use ART to try to “bring back” the northern white rhino is a complex, highly difficult endeavor, and creating early stage embryos is but the first step on a long journey.

Recovering immature eggs and maturing them in vitro is a difficult task in itself, particularly when eggs are being recovered from females with reproductive issues. The next step, injecting the eggs with sperm and allowing them to develop into early stage embryos and placing them into the uterus of surrogate is also complicated. Developing a viable pregnancy and having the surrogate carry it to term with a successful delivery is another hurdle.

Once it is reliable, ART may play a vital role in securing the future for rhino populations. There recently have been other important ART advances for rhinos.

In July, scientists at the San Diego Zoo’s Institute for Conservation Research produced a southern white rhino calf using frozen semen and artificial insemination (AI).

In May, reproductive scientists from the South East Zoo Alliance for Reproduction and Advanced Conservation (SEZARC) induced ovulation in a greater one-horned rhino (Rhinoceros unicornis) and used AI to produce a calf at Zoo Miami.

In 2014, the Cincinnati Zoo & Botanical Garden’s Center for Conservation & Research of Endangered Wildlife (CREW) and the Buffalo Zoo in New York, produced a greater one-horned rhino calf using AI with the sperm of a deceased male who never contributed to the gene pool of the species during his lifetime.

These are but a few of the more recent achievements; we encourage reading Pennington and Durrant’s historical review of rhino ART efforts in Mammal Review and the Nature article referenced above for more information.

The Northern White Rhino
The conservation community and international governments should have attacked conserving the northern white rhino more vigorously much earlier – certainly before only a handful were left in captivity. The IRF spent millions of dollars protecting the northern white rhino in Garamba National Park in the Democratic Republic of Congo but, despite protection, the species was lost when the Park became a conflict zone and we had to pull out to ensure the safety of our staff. Governments in range states are responsible for conserving their biological heritage, but if no political will is present, there is only so much that outside stakeholders can do.

If and when northern white rhinos are successfully created, inevitably there will be issues over where to locate them – the countries in which they perished are still in conflict, and invariably, there is an ongoing poaching threat, making repatriation improbable. There also are complex ethical issues to be resolved: should we “re-create” a subspecies that has gone extinct? Furthermore, the initial attempt at maintaining an ex situ breeding population failed, which begs the question, what will we do different to make sure the next effort succeeds?

Finally, ART work is exceedingly expensive. Some argue that funding at the level that has been raised for the work with northern white rhinos could be used for field conservation. However, we do not believe that the donors are in all cases the same; thus, the funding being used to support ART work is likely not competing for funding that would be available for in situ rhino conservation.

Application to other rhino species
All five rhinoceros species are in peril, with four of the five (with the exception of the white rhino) listed as threatened on the IUCN Red List of Threatened Species. The most critically endangered species, the Sumatran rhino (Dicerorhinus sumatrensis), numbers fewer than 80 individuals scattered in four fragmented locations in Indonesia.

Our hope is that critically endangered rhino species may someday benefit from this work, and that perfecting ART methods with the non-threatened white rhino may help them in the future.

But it’s also very possible that the technology, which could contribute to increasing numbers very slightly in the big scheme of things, may not be in place in time to contribute to increasing Sumatran rhino numbers either; the species is declining precipitously despite in situ protection and some success with natural breeding in captivity.

Nevertheless, efforts to continue developing ART should definitely move forward. No species has been saved by “high tech” approaches alone, but such technologies have proven valuable when integrated with natural breeding and protection of wild populations.

To-date, as described by in a paper by Howard and colleagues in Animal Conservation, the black-footed ferret (Mustela nigripes) is the only species where AI (with frozen sperm) has been used for genetic restoration. However, because there are no wild northern white rhinos left and the two still alive cannot reproduce naturally, it would be a long time, perhaps two decades, before enough rhinos could be created to form a viable population – Population Viability Analysis has shown that populations of fewer than 15 rhinos are not viable.

There is no easy answer for ensuring the survival of critically endangered rhinoceros species – but we do need to tackle the myriad of challenges they face using multi-faceted approaches. ART is one of the developing tools in the toolkit.