Smithsonian’s National Zoo in Washington D.C. is mourning the death of a Przewalski’s horse who lived to a great age.
Minnesota was euthanized on Tuesday morning at the age of 29. The average life expectancy for male Przewalski’s horses is 15 years in human care.
A final pathology report is expected to provide more information on his death.
Animal care staff had been closely monitoring Minnesota for health issues related to his advanced age, including chronic dental disease, weight loss and lethargy.
Working with zoo nutritionists, keepers modified Minnesota’s diet to ensure he was receiving the optimal amount of daily nutrients.
When his condition did not improve, zoo veterinarians anesthetized Minnesota to try to determine the underlying cause of his symptoms.
Despite conducting a full physical exam and analyzing blood samples, veterinarians were unable to determine the exact cause of illness.
Over the weekend, staff determined that his quality of life had worsened and elected to humanely euthanize him based on his poor long-term prognosis.
He was born at the Minnesota Zoo on April 10, 1988, and arrived at the Smithsonian Conservation Biology Institute in Front Royal, Virginia., in June 2004. He went to the Smithsonian National Zoo in June 2005 but returned to his previous Virginia home in February 2008.
In 2014, Minnesota came back to Washington, D.C., to serve as a non-breeding companion for Rose-Marie, the Zoo’s 31-year-old female Przewalski’s horse. Keepers describe Minnesota as a good-natured horse who was very attentive to Rose-Marie and stuck close by her side whenever they explored their habitat.
Most zoo animals participate in a breeding program called the Species Survival Plan.
Under the plan, scientists determine which animals to breed by considering their genetic makeup, nutritional and social needs, temperament and overall health.
In 2008, veterinarians from the zoo and the Smithsonian Conservation Biology Institute performed the first successful reverse vasectomy on Minnesota.
The procedure was the first of its kind to be performed on an endangered equid species.
Rather than breed, Minnesota acted as an educational ambassador for his species, illustrating the social nature and behavior of Przewalski’s horses to scientists, keepers and zoo visitors.
The Przewalski’s horse is a species native to China and Mongolia that was declared extinct in the wild in 1969.
Today, about 1500 Przewalski’s horses reside at zoological institutions worldwide, carrying genes from only 14 original animals.
Hunting, loss of habitat and loss of water sources threaten horses that have been reintroduced to their native habitats.
Smithsonian staff work to maintain breeding populations that serve as a source of animals for reintroduction.
In 2013, scientists at Smithsonian Conservation Biology Institute celebrated a huge breakthrough for the survival of this species with the birth of a female Przewalski’s horse — the first born via artificial insemination.