Patience is a strong requirement when it comes to a giant panda's pregnancy. Is this a pregnancy or is it a pseudo pregnancy? Zoo's try innumerable ways, urine samples and ultra sound in order, to predict a possible due date. Now, with the help of science the zoo's have a unique test that proved very effective this year.
Congratulations to the panda team at the Memphis zoo that has developed this test.
BARTHOLOMEW SULLIVAN - Scripps Howard News Service August 26, 2013 - 6:19 pm EDT
WASHINGTON — The "due date" for the baby giant panda born Friday at the Smithsonian National Zoo in Washington was determined using a test developed by the panda team at the Memphis Zoo, according to scientists at both institutions.
The test analyzed Mei Xiang's levels of the prostaglandin metabolite, a lipid or fatty acid, to predict the birth in the last week of August. Mei Xiang gave birth to an apparently healthy, 4.8-ounce cub on Friday afternoon and a stillborn twin on Saturday night.
Andy Kouba, director of conservation research at the Memphis Zoo, said two tests — one determining if a panda is pregnant, and the other for narrowing the due date — have been designed at the Memphis Zoo, where frozen specimens of the animals' urine are sent to be tested.
The test for pregnancy is the measure of a hormone called ceruloplasmin associated with the immune system which allows zoo personnel to distinguish between a true pregnancy and a pseudo-pregnancy common in bears and canines.
In a pseudo-pregnancy, an animal exhibits behaviors similar to one that is pregnant, such as den-building, Kouba explained. Before the test was developed, a test of the animal's steroid profile wasn't useful because it would look the same in both true and pseudo-pregnancies.
The only way to detect an early pregnancy before that test, if the animal would cooperate, was ultrasound.
Panda pregnancies are notoriously difficult to detect because the cubs are born so small and because the gestation period is hard to determine because of sometimes-delayed implantation of the embryo after breeding. A panda can be born within 90 days of breeding but also as many as 300 days afterward, Kouba said.
The prostaglandin metabolite spikes twice late in pregnancy. The Memphis Zoo lab scientists predicted the exact date of panda twin brothers born in July to Lun Lun in Atlanta and predicted in Mei Xiang's case a due date of Saturday, plus or minus one day. The healthy cub was born a day early and the stillborn cub was born on the exact date.
The National Zoo's panda's sex has yet to be determined. Mei Xiang was artificially inseminated and the cub's father, from either San Diego or Atlanta, will be determined by DNA tests after a brief physical exam was performed Sunday morning. (The Republic, Columbus, Indiana)
(Reach The Commercial Appeal of Memphis Washington correspondent Bartholomew Sullivan at email@example.com.)