Photo by Kevin H.

It’s another year, another false pregnancy for the National Zoo’s giant panda duo. The Zoo has announced that female giant panda Mei Xiang is not with cub, and the 24-hour pregnancy watch which has been on for the last several weeks has been called off.

As has been the case for several years running now, Mei Xiang was experiencing a “pseudopregnancy,” in which her hormone levels were indicative of an impending Butterstick. But despite pacing around her den and a changing diet, Mei “stopped allowing animal keepers to perform ultrasound exams on her in early July.”

It’s Mei’s sixth false pregnancy. Next year is probably her last chance to produce a cub. Cubs born in the United States get to stay for four years; Mei Xiang and the Zoo’s male giant panda, Tian Tian, will be in Washington until 2015.

Perhaps realizing the crushing news they were preparing to impart to the general public today, the Zoo released another round of cheetah cub photos yesterday. Never has that level of squee felt like such cold comfort.