ABSTRACT
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.
Subject(s)
Ursidae , Animals , Feeding Behavior , Plant Leaves , Eating , FoodABSTRACT
Oxygen vacancy sites on a catalyst surface have been extensively studied and been proved to promote the adsorption and activation of carbon dioxide. We use Sn-doped ZrO2 to prepare a Zr/Sn catalyst rich in oxygen vacancies (OVs) by co-precipitation. The yield of dimethyl carbonate is 5 times that of ZrO2. Compared with the original ZrO2, Zr/Sn exhibits a higher specific surface area, number of acid-base sites and a lower band gap, which improves the conductivity of electrons and creates more surface. The number of reaction sites greatly enhances the adsorption and activation capacity of CO2 molecules on the catalyst surface. In situ infrared spectroscopy shows that CO2 adsorbs on oxygen vacancies to form monomethyl carbonate, and participates in the reaction as an intermediate species. This work provides new clues for the preparation of ZrO2-based catalysts rich in oxygen vacancies to directly catalyze the synthesis of dimethyl carbonate from methanol and CO2.
ABSTRACT
The different SSCP patterns of the follicle stimulating hormone beta (FSHß) gene amplified by three pairs of primers were sequenced. Comparisons among the three nucleotide sequences of three genotypes indicated that three base substitutions (A213T, A91G, and A89C) were detected in FSHß gene, which A213T substitution led to one amino acids mutation (Lys > Met), and the other two substitutions were synonymous mutations. The AA, AB and BB genotypes patterns obtained by FSHß primer1 had evident relation with the litter traits, but the SSCP genotypes patterns obtained by FSHß primer2 and primer3 had no evident relation with the litter traits in giant panda. The giant panda with AA and AB genotype had the largest litter size and multiparity rate compared with the BB genotypes (P < 0.05). We speculated that the giant pandas with the A allele have better litter traits than those with the B allele.
