Reproduction Cycle Could be Manipulated to Save Endangered Iberian Lynx

The unparalleled longevity of a hormone-producing tissue in the Eurasian lynx could possibly be utilized to assist in the conservation of the endangered Iberian lynx, one of the most threatened wild cats on Earth.

The Corpus luteum (CL) is the hormone-producing tissue responsible for restricting the Eurasian lynx to only one opportunity to become pregnant each year, and scientists suggest that this holds the keys to perhaps unlocking door to enabling the lynx to have the opportunity to reproduce multiple times a year.

Because the Eurasian lynx is so closely related to the Iberian lynx, researchers hope that the CL can be manipulated in the endangered cat to enable them to breed more than once a year.

Scientists from the Leibniz Institute for Zoo and Wildlife Research in Berlin conducted the research, which is published in the journal PLOS One.

Lynx breeding programs in Spain and Portugal are attempting to rebuild populations of Iberian lynx, but their efforts are stymied if a female lynx does not become pregnant in the window of five to seven days she has each year.

The lynx's CL produces the pregnancy hormone progesterone, and the female lynx is capable of maintaining her CL within her ovaries many years on end (the longest known of any mammal). In other species, the CL is known to disappear shortly after the female gives birth.

"Surprisingly, the female lynx can switch off its CL's progesterone production when entering a new cycle during spring or before giving birth without destroying the CL," the researchers said in a statement. "Later on, progesterone is produced continuously, suppressing the follicular development in the ovary and therefore preventing the onset of a second oestrus cycle within the same year."

What this amounts to is only one real opportunity for the female lynx to become pregnant in a year, and if she fails to become pregnant within the narrow window of time her body allows, she must wait again for another year.

In the wild, this can be devastating for a species trying to sustain its population.

"This study provides essential information for the assisted reproduction techniques in Iberian lynx which continue to be refined and improved, such as artificial insemination or embryo-transfer," the researchers said in a statement. "Future research will focus on the manipulation of reproductive cycles to increase the reproductive output for breeding centers and to discover the molecular mechanism underlying this unique phenomenon."