Diet And Digestion Of Giant Panda With Reference To Its Nutritional And Energetic Strategy

The giant panda (Ailuroplda melanoleuca) is a kind of rare and endangered species that is endemic to China, and is also the flagship species of our country, even important to the global bio-diversity protection work. Therefore, giant pandas have been receiving the high concern of the international community all the time. Giant pandas are mainly feed on kinds of bamboos, but have very low digestion rate. Thus, the choice to different species of bamboos in every distributing area by giant pandas, and the particular digestion rates and utilization data of the bamboos are main scientific basis to set down the protection countermeasures.In view of this, we took researches in the Salvation and Breeding Center for Rare and Endangered Wildlife of Shaanxi Province and the Laoxiancheng Nature Reserve of Shaanxi Province. We adopted the cafeteria measurement, total feces collection method, acid insoluble ash analysis (AIA) and nutrient mensuration, analyzed the edible and preferred bamboo species list, mensurated and compared the normal nutrient components of these bamboos, and studied the digestion rates to different bamboos by giant pandas. Meanwhile, combined with the field investigations, we also systematically studied the choice and utilization countermeasure to bamboos by the giant pandas of the Qinling Mountain. The main results are showed as follows:1. We used the cafeteria measurement, investigated the choice of giant pandas to 97 bamboo species which belonged to 16 genera. Then we found that the giant pandas refused to feed on 5 kinds of bamboos, Phyllostachys heterocycla cv. Pubescens,Phyllostachys iridescens,Phyllostachys nigra,Phyllostachys praecox cv.Prevernalis,Phyllostachys parvifolia, and all the five species belonged to Phyllostachys. There were 93 species of bamboos that were chosen by giant pandas, accounts for 94.9% of the all testing bamboos. The results indicated that the captive giant pandas had wide-adaptabilities to nearly all the bamboos.2. According to the bamboo choice study, the captive giant pandas had significant difference choice (P＜0.05) to 13 kinds of bamboos, and even had significant difference choice (P<0.05) to the diverse vegetative organs of the one species. Meanwhile, the average leaf-weight and leaf-area of all 13 kind of bamboo in present study were highly positively correlated, and the linear relationship between the average leaf-weight and leaf-area in this study was very significant (R2=0.9907). According to the analysis and comparison to the morphology and nutritional factor of the 13 bamboos, we found that giant pandas took the bamboo species with weightier and larger leave as the prior choice. Therefore, the morphology but the nutritional factor was the leading factor in the bamboo choice study by giant pandas.3. We adopted the total feces collection method and acid insoluble ash analysis (AIA), mensurated the digestion rates to the crude protein (CP), crude fat (ether extract, EE) and coarse fibre (CF) of different bamboos. The results indicated that differences of the digestion rates mensurated by these two method were not significant (P>0.05). Therefore, AIA analysis was reliable in the digestion rate mensuration of adult giant pandas, and could be used to the study and monitoring work of wild giant pandas.4. Comparison of digestion of captive and wild giant panda shows that the digestion of the former is more than the later. It is inferred that fast excretion and low digestion rate of the giant pandas may be a kind of adaptation countermeasure, which is a Giant panda nutrition and energy strategy on bamboo which have low nutrition but biomass-rich.Above all, these researches have strengthened our understanding to the bamboo choice and utilization countermeasure of giant pandas, the results can be used in the build of bamboo-supply area for captive giant pandas, the biomass statistics of edible bamboos in the Qinling Mountain, habitat recovery, and the ecological corridor build. The basic data also could be scientific basis of the giant panda's protection countermeasure of the Qinling Mountains.