Scientists observe reproductive seasonality in male giant pandas

Apr 04, 2012
The state-of-the-art Chengdu Research Base of Giant Panda Breeding has provided an unprecedented opportunity for researchers to study multiple pandas in a single location. Credit: Zhang Zhihe, Chengdu Research Center for Panda Breeding.

A three-year study of giant pandas published today in Biology of Reproduction's Papers-in-Press reveals that reproductive seasonality exists not only in female pandas, but in male pandas as well.

According to the authors of the study, this new understanding of the regulators of male reproductive function will allow continued improvement of the captive panda management program and will, one day, assist in reintroducing into the wild.

The is a specialized bear whose wild habitat now consists of only a few mountain ranges in central China. Attempts at preserving this endangered species have met with varying success, but over the last decade, substantial progress in giant panda breeding within China has resulted in a significant increase in the population of captive pandas.

Female panda reproduction has been thoroughly studied, and it is well known that a panda's estrus, the state of sexual excitement that immediately precedes ovulation, occurs only once a year, sometime between February and May, and lasts only 24 to 72 hours. Few studies have examined male reproductive capacity and physiology in similar detail, and none involved sample sizes larger than one or two individuals.

Now, an international research team led by Dr. Copper Aitken-Palmer of the Smithsonian Conservation Biology Institute and Dr. Rong Hou of the Chengdu Research Base of Giant Panda Breeding, along with senior researchers Drs. David Wildt, Mary Ann Ottinger, and the late JoGayle Howard, has published the results of their study of eight male giant pandas in a captive in China.

The team evaluated the interrelated seasonal changes in male panda androgen levels, sperm concentration, testes size, and , and found that unlike what is found for females, in the male giant panda varies throughout the year. Waves in male giant panda reproductive activity occurred 3 to 5 months before the interval when most females displayed their estrus, presumably in order to prepare for and then accommodate the brief and unpredictable female estrus.

These findings not only fill a knowledge gap, but the authors believe that they can be used to help researchers collect and preserve only the highest-quality panda spermatozoa for artificial insemination, an increasingly important tool in genetic diversity management within the captive panda population.

Explore further: Telling the time of day by color

More information: "Reproductive Seasonality in the Male Giant Panda", Biology of Reproduction (in press).

Related Stories

China announces first panda from frozen sperm

Jul 24, 2009

(AP) -- China announced the first successful birth of a panda cub from artificial insemination using frozen sperm, giving a new option for the famously unfertile endangered species, officials said Friday.

China panda baby boom aids against extinction

Oct 26, 2010

(AP) -- China's panda population is booming this year thanks to a record number of births in captivity, a rare accomplishment for the endangered species known for being poor breeders.

China to release six pandas into wild

Dec 21, 2011

Six captive-bred pandas will be freed into an enclosed forest in southwestern China next year in the first mass release of the highly endangered animals, the official Xinhua news agency said Wednesday.

US zoo receives $4.5 mn panda donation

Dec 19, 2011

The National Zoo in Washington announced Monday it had received a $4.5 million donation from a rich US benefactor which will fund a five-year study into preservation of the giant panda.

Plan to reintroduce giant pandas to the wild

Dec 07, 2010

(PhysOrg.com) -- Scientists in China have been so successful at breeding giant pandas in captivity that they are now planning for their reintroduction to the wild with 15 years.

Pandas mate with help at the National Zoo

Mar 24, 2008

U.S. veterinarians have artificially inseminated Mei Xiang, a female giant panda at the Smithsonian's National Zoo, after natural mating was unsuccessful.

Recommended for you

Telling the time of day by color

14 hours ago

Research by scientists at The University of Manchester has revealed that the colour of light has a major impact on how the brain clock measures time of day and on how the animals' physiology and behavior adjust accordingly. ...

Aphrodisiac for fish and frogs discovered

19 hours ago

A supplement simply added to water has been shown to boost reproduction in nematodes (roundworms), molluscs, fish and frogs – and researchers believe it could work for humans too.

Evolution puts checks on virgin births

20 hours ago

It seems unnatural that a species could survive without having sex. Yet over the ages, evolution has endowed females of certain species of amphibians, reptiles and fish with the ability to clone themselves, ...

Humans can't resist those puppy-dog eyes

Apr 16, 2015

When humans and their four-legged, furry best friends look into one another's eyes, there is biological evidence that their bond strengthens, researchers report.

Roundworm parasite targets canine eyes

Apr 16, 2015

(HealthDay)—A small number of dogs and cats across the United States have been infected by a roundworm parasite that targets the eye, according to a new report.

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

panorama
not rated yet Apr 04, 2012
Because sometimes the guys are tapped out too, but check your lease panda's...

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.