On August 30, the China Giant Panda Protection and Research Center’s official Weibo account shared a video showcasing “Fu Bao‘s” daily feeding habits. The following day, the center responded in the comments that “Fu Bao” has entered a pseudopregnancy state.
Between March and April, “Fu Bao” began to show hormonal changes and atypical signs of first estrus. Since mid-August, noticeable signs have emerged, including decreased appetite, reduced consumption of bamboo and supplementary food, decreased stool output, less activity, increased resting time, and more frequent water play. Physical examinations revealed significant physiological changes in “Fu Bao’s” external genitalia. Based on behavioral changes and examination results, the care team concluded that “Fu Bao” has entered a pseudopregnancy state. Following this announcement, the topic #Fu Bao has entered a pseudopregnancy state# trended on social media, sparking widespread discussion among netizens.
So, what is pseudopregnancy in giant pandas, and how can one determine if a panda is pregnant?
A female giant panda may experience pseudopregnancy if she has not mated after her estrus or has mated but not conceived. Despite this, she exhibits behaviors typical of a normal pregnant panda, known as pseudopregnancy.
Behaviorally, there is little difference between a pseudopregnant panda and a genuinely pregnant one; both may exhibit lethargy, decreased appetite, and even a cessation of eating. Physiologically, their hormone levels are almost identical, with only subtle differences. Typically, the duration of pseudopregnancy in giant pandas lasts about 1 to 2 months, varying by individual.
Additionally, predicting whether a panda is pregnant can be challenging, as recorded gestation periods for giant pandas range from 72 to 324 days. Signs of pregnancy may not appear until at least two months after estrus, and there is a phenomenon known as delayed implantation of embryos, making it difficult to perform ultrasounds on panda cubs.
To determine if a giant panda is pregnant, three main methods are generally employed:
- External Observation: After mating, pregnant pandas may exhibit abnormal signs such as decreased appetite, cautious movements, aversion to crowds, and increased sleep duration.
- Hormone Measurement: The levels of pregnancy hormones in the blood and urine of genuinely pregnant and pseudopregnant pandas are significantly higher than in normal pandas.
- Ultrasound Diagnosis: This method utilizes the physical properties of ultrasound to detect the presence of embryos, fetal movement, and fetal heartbeat, thereby facilitating pregnancy diagnosis.
