Washington, Nov 14 : A female rhinoceros has successfully given birth to a healthy offspring after being artificially inseminated (AI) with frozen and thawed semen, say German researchers.
Experts at the Leibniz Institute for Zoo and Wildlife Research, Berlin, Zoo Budapest and the University of Veterinary Medicine, Vienna, have revealed that using semen collected from a 35-36 year-old Southern white rhinoceros, frozen for 2 to 3 years and then thawed, a 30-year-old female rhinoceros was artificially inseminated in two attempts.
The first failed, but the second resulted in pregnancy and the birth of a healthy offspring.
At the time of conception, the female was housed at the Budapest Zoo in Hungary and the male donor in Colchester Zoo in the United Kingdom.
Techniques for AI in rhinoceros have improved in recent years and the first live birth by AI occurred in 2007.
However, that instance used fresh semen from a male rhinoceros in the same zoo, limiting the widespread use of the technique.
By showing that frozen semen could be thawed and used to successfully inseminate a female at a remote location, the researchers have opened a new avenue to the preservation of endangered species.
Semen samples can be collected and preserved from both wild and captive populations to maintain a genome resource bank and to boost reproduction in these megaherbivores.
"This achievement joins a fairly short list of fewer than 30 wildlife species, most of which are closely related to domestic species, in which artificial insemination with frozen-thawed semen has been successful in producing live offspring. The use of frozen-thawed semen holds great potential as a means to overcome the crisis most captive and wild rhinoceros populations are facing in various ways," Dr. Robert Hermes, Med. Vet., and colleagues state.
The study is scheduled for publication in Theriogenology.