旅美熊猫梅香和天天将继续留美
The National Zoo said Wednesday that China has granted an extension of its lease of Washington's two giant Pandas, Mei Xiang and Tian Tian.
美国国家动物园在周三表示，中国已经同意延长华盛顿的两只大熊猫梅香和天天的租期。
Zoo Director Dennis W. Kelly was in China last week seeking to negotiate a new panda arrangement to replace the 10-year, $10 million lease that expired Dec. 6. China owns and leases all giant pandas in U.S. zoos.
动物园园长丹尼斯 W·凯利上周来到中国协商新的熊猫租借方案来代替在12月6号到期的一千万租借大熊猫十年的租约。中国仍然对美国动物园里租借的所有熊猫享有拥有权。
The zoo badly wants cubs for research purposes. And recent science suggests that if a female panda has not become pregnant for several years, it is increasingly unlikely that she will be able to get pregnant in the future.
处于研究目的，园方十分希望能够获得熊猫幼崽。但是最近科学家认为如果一直雌性熊猫长年都未怀孕的话，那么在之后的时间中怀孕的可能性就更小了。
"We've not had a cub here in the last five years," Kelly said in an interview in July.
“过去五年中我们都没有熊猫幼崽，”凯利在7月的一次访问中说。
"There's some data that suggests that after four [breeding] tries, there's something [negative] going on," he said in July. Pandas generally mate once a year.
“一些资料表明，在之前的四次（繁殖）努力失败后，存在着一些不利因素，”他在7月的采访中说道。熊猫一般每年只交配一次。
Zoo scientists are planning for Mei Xiang's upcoming breeding season. She went into heat last Jan. 9 and Jan. 15 the year before. And the zoo said it would not move her during her annual pregnancy watch, which usually lasts until spring.
动物园的科学家们正在为梅香的下一个繁殖期做准备。她在去年的发情期是在1月9号和15号。动物园方面说，从对她每年的怀孕期的观察看来她发情期的时间应该是稳定的，她的发情期通常会持续到春季。
The Memphis Zoo's panda pair, residents there since 2003, have not produced any offspring.
孟菲斯动物园的一对大熊猫从2003年入园以来目前还未产子。
