The giant panda (GP) was the most endangered species in China, and gut microbiota plays a vital role in host health. To determine the differences of the gut microbiota among the male, female and pregnant GPs, a comparative analysis of gut microbiota in GPs was carried out by 16S rRNA and ITS high-throughput sequencing. In 16S rRNA sequencing, 435 OTUs, 17 phyla and 182 genera were totally detected. Firmicutes (53.6%) was the predominant phylum followed by Proteobacteria (37.8%) and Fusobacteria (7.1%). Escherichia/Shigella (35.9%) was the most prevalent genus followed by Streptococcus (25.9%) and Clostridium (11.1%). In ITS sequencing, 920 OTUs, 6 phyla and 322 genera were also detected. Ascomycota (71.3%) was the predominant phylum followed by Basidiomycota (28.4%) and Zygomycota (0.15%). Purpureocillium (4.4%) was the most prevalent genus followed by Cladosporium (2.5%) and Pezicula (2.4%). Comparative analysis indicated that the male GPs harbor a higher abundance of phylum Firmicutes than female GPs with the contribution from genus Streptococcus. Meanwhile, the female GPs harbor a higher abundance of phylum Proteobacteria than male GPs with the contribution from genus Escherichia/ Shigella. In addition, the shift in bacteria from female to pregnant GPs indicated that phylum Firmicutes increased significantly with the contribution from Clostridium in the gut, which may provide an opportunity to study possible associations with low reproduction of the GPs.

Bamboo is the main food source of the giant panda. To increase bamboo intake in captive giant pandas, we studied factors affecting the bamboo intake. Fourteen healthy captive giant pandas in Dujiangyan Base of China Conservation and Research Center for The Giant Panda (" Dujiangyan Base "for short) were selected as research objects. Bamboo feeding experiment was conducted to study the effects of seasons, bamboo age, slope orientation and felling-feeding time on bamboo intake of the giant panda. We found that the type of bamboo that captive giant pandas feed on was rich in spring and summer, but relatively simple in winter. With the increase of bamboo age, the intake of bamboo leaves decreased, while bamboo culms increased. The feed intake of 1-year-old bamboo leaves and 5-year bamboo culms reached the highest respectively. The slope orientation of bamboo growth also affected the panda's bamboo intake. Moreover, the bamboo intake reached the highest when the felling-feeding time was less than 24h. In short, we confirmed that seasons, bamboo age, slope orientations and felling-feeding time were factors affecting bamboo intake for captive giant pandas. This study was expected to provide scientific guidance improving the feeding behavior management of captive giant pandas.

Infant call structure should have evolved to elicit maximum maternal attention and investment. Neonates of giant pandas produce three types of vocalizations reported to be vitally important in the context of mother–infant communications. However, how cubs, 0–15 days old, communicate with their mothers to elicit maternal care remains unknown. We analyzed 12 different call parameters of 3475 squawks, 1355 squalls, and 491 croaks from 11 captive giant panda (Ailuropoda melanoleuca) neonates from age 0 to 15 days. In playback experiments, we also tested whether mothers could detect ultrasound. Our results show that neonates use broadband calls with ultrasonic frequencies up to 65 kHz to convey information about their physiological needs and to attract maternal care. In playback experiments, we tested if mothers reacted differently to broadband calls (BBC) than to artificially altered calls that included only frequencies <20 kHz (AUDC) or calls that included only frequencies >20 kHz (USC). Playback confirmed that, although adult females responded significantly less often to USC, BBC than to or AUDC, they could detect USC, BBC and generally made appropriate behavioral responses, indicating a potential benefit for neonates to utilize ultrasonic and broadband frequencies. Our findings provide a new insight into mother–infant communication in giant pandas and will be helpful for reducing the mortality of cubs, younger than 1 month old, in captivity.

Bamboo is the main food source of the giant panda. To increase bamboo intake in captive giant pandas, we studied factors affecting the bamboo intake. Fourteen healthy captive giant pandas in Dujiangyan Base of China Conservation and Research Center for The Giant Panda (“Dujiangyan Base” for short) were selected as research objects. A bamboo feeding experiment was conducted to study the effects of seasons, bamboo age, slope orientations where bamboo grows and felling-feeding time on bamboo intake of the giant panda. We found that the type of bamboo that captive giant pandas feed on was abundant in spring and summer, but relatively homogeneous in winter. With the increase of bamboo age, the intake of bamboo leaves decreased, while bamboo culms increased. The feed intake of 1-year-old bamboo leaves and 5-year-old bamboo culms reached the highest respectively. The slope orientation also affected the panda's bamboo intake, and the bamboo growing on sunny slopes or semi-sunny slopes was more favored by captive giant pandas. Moreover, the bamboo intake reached the highest when felling-feeding time was less than 24 h. In short, we confirmed that seasons, bamboo age, slope orientations and felling-feeding time were factors affecting bamboo intake for captive giant pandas. This study was expected to provide scientific guidance improving the feeding behavior management of captive giant pandas.