Navigation Links
First successful reverse vasectomy on endangered species performed at the National Zoo
Date:6/17/2008

Veterinarians at the Smithsonian's National Zoo have performed the first successful reverse vasectomy on a Przewalski's horse (E. ferus przewalskii; E. caballus przewalskii classification debated), pronounced zshah-VAL-skeez. Przewalksi's horses are a horse species native to China and Mongolia that was declared extinct in the wild in 1970. Currently, there are approximately 1500 of these animals maintained at zoological institutions throughout the world and in several small reintroduced populations in Asia. This is the first procedure of its kind to be performed on an endangered equid species.

The genes of Minnesotathe horse who underwent the surgeryare extremely valuable to the captive population of the species, which scientists manage through carefully planned pairings to ensure the most genetically diverse population possible. The horse was vasectomized in 1999 at a previous institution so that he could be kept with female horses without reproducing. He came to the National Zoo in 2006.

While surveying the captive North American population of Przewalski's horses, scientists realized Minnesota's genetic value. Based on his ancestry, he is the seventh most genetically valuable horse in the North American breeding program. Zoo scientists were confident that if they could successfully reverse the vasectomy, Minnesota would be able to sire a foal through natural mating.

"The major challenge we faced was that this procedure had never been performed on an equid, let alone a critically endangered species," said Dr. Budhan Pukazhenthi, a reproductive scientist at the National Zoo's Conservation and Research Center in Front Royal, Va. "We had to develop all new protocols ourselves."

The team sought the expertise of Dr. Sherman Silber, a St. Louis-based urologist who pioneered microsurgery for reverse vasectomies in humans and had been successful in vasectomizing and then subsequently reversing vasectomies in South American bush dogs at the St. Louis Zoo.

"Although our team is very experienced in horse anesthesia and surgery, by using the specialized professional skills of Dr. Silber, we greatly increased the likelihood of success," said Dr. Luis Padilla, associate veterinarian at the Conservation and Research Center.

Silber, working with the Zoo's team of veterinarians and reproductive scientists, first performed the operation on Minnesota in March 2007. That procedure proved unsuccessful, possibly due to the presence of scar tissue or the fact that the horse was positioned on its side, making it difficult to perform the surgery. Silber was confident that if the horse could be placed on its back, the procedure would be a success. Laying an anesthetized horse on its back for a prolonged period of time can be challenging due to their size and physiology. Veterinarians decided it could be done, but only if the surgery time was kept to a minimum. In October 2007, the team operated on Minnesota againcompleting the procedure in an hour. Six months later, the Zoo's veterinarians and reproductive scientists collected a semen sample from the horse that indicated the procedure had been a success.

"I've always dreamed of using my expertise to contribute in some way to wildlife survival," said Dr. Silber. "It was exciting to pioneer a new procedure for which humans were the 'test animal.'"

National Zoo scientists hope to pair Minnesota with a suitable female in July. His genes will infuse genetic diversity in a Przewalski's horse population that is based on genes from only l4 original animals. National Zoo scientists are researching ways to improve fertility and produce more offspring in the aging, captive population. Bolstering the population translates into more horses for future reintroduction programs, essential for a critically endangered species. Currently, National Zoo scientists are working in remote areas of China using radio collars and Geographic Information System technology to map the movements of Przewalski's horses reintroduced by Chinese colleagues into their former habitat.

This breakthrough also has important implications for how endangered species in captivity are managed. The new knowledge could allow males and females of a species to be exhibited together but temporarily prevented from producing offspring if the Species Survival Plana cooperative breeding program among zoosdoes not recommend them for breeding.


'/>"/>

Contact: Sarah Taylor
taylors@si.edu
202-633-3081
Smithsonian
Source:Eurekalert  

Related biology news :

1. Which came first, the moth or the cactus?
2. First all-African GM crop is resistant to maize streak virus
3. Scientists retrace evolution with first atomic structure of an ancient protein
4. CU-Boulder team discovers first ancient manioc fields in Americas
5. First finding of a metabolite in 1 sex only
6. First orchid fossil puts showy blooms at some 80 million years old
7. First individual genome sequence published
8. U of M begins nations first clinical trial using T-reg cells from cord blood in leukemia treatment
9. UNH becomes first university in nation to use landfill gas as primary energy source
10. Scientists in first global study of poison gas in the atmosphere
11. Weight gain between first and second pregnancies associated with increased odds of male second child
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
First successful reverse vasectomy on endangered species performed at the National Zoo
(Date:6/21/2016)... 21, 2016 NuData Security announced today that ... of principal product architect and that Jon ... customer development. Both will report directly to ... moves reflect NuData,s strategic growth in its product ... customer demand and customer focus values. ...
(Date:6/15/2016)... ALBANY, New York , June 15, 2016 ... published a new market report titled "Gesture Recognition Market ... Trends and Forecast, 2016 - 2024". According to the ... at USD 11.60 billion in 2015 and is ... and reach USD 48.56 billion by 2024.  ...
(Date:6/7/2016)... , June 7, 2016  Syngrafii Inc. and ... business relationship that includes integrating Syngrafii,s patented LongPen™ ... project. This collaboration will result in greater convenience ... credit union, while maintaining existing document workflow and ... ...
Breaking Biology News(10 mins):
(Date:11/30/2016)... , November 30, 2016 The global ... few players hold a dominant share in the overall ... Laboratories International, Inc., and Merck KGaA, held a lion,s ... Transparency Market Research observes that these companies are expected ... development products that are do not require rabbit pyrogen ...
(Date:11/30/2016)... VANCOUVER , Nov. 30, 2016 /PRNewswire/ -  Equicare ... coordination solutions, has been recognized as one of the ... 100, an annual international listing that distinguishes the top ... "We,ve pushed a great step forward this year continually ... growing our own customer base and team," says ...
(Date:11/30/2016)... -- Part of 5m$ Investment in Integrated Drug ... , ... today announced that it had successfully completed the expansion of ... increased the Screening Collection to over 400,000. The new compounds ... the company. This expansion, complemented by new robotics and compound ...
(Date:11/30/2016)... Triangle Park, NC (PRWEB) , ... November 30, ... ... development company engaged in the development of a new orally administered treatment for ... testing and neuroimaging results of a Phase 2a clinical trial of T3D-959 in ...
Breaking Biology Technology: