Molecular analysis of dispersal in giant pandas

Although dispersal in the giant panda (Ailuropoda melanoleuca) is a demographic mechanism which can potentially counteract the negative effect of habitat fragmentation, little is known about dispersal in this species because of difficulties in observing individuals. Using data from faecal microsatellite genotyping, we compared the spatial distribution of giant pandas in two populations and the proximity of relatives in one key population to infer their dispersal pattern. We conclude that giant pandas exhibit female-biased dispersal because: (i) vAIc (variance of assignment index) for females was significantly larger than for males, suggesting that females comprise both 'local' and 'foreign' genotypes; (ii) the average spatial distance of related female dyads was significantly larger than that of males; (iii) larger r (relatedness), F(ST) (genetic variance among populations) and mAIc (mean of assignment index) values were found in males using the software FSTAT, although the differences were not significant; (iv) males set up territories neighbouring to their birth place; (v) significant population structure using microsatellites with a concomitant lack of mitochondrial structure was found in a previous study, possibly indicating more extensive female dispersal; and (vi) female-biased dispersal was strongly supported by evidence from concomitant ecological studies. Considering previous ecological data and life-history characteristics of the giant panda, female-biased dispersal is most likely to be due to competition for birth dens among females, inbreeding avoidance and enhancing inclusive fitness among related males.     

甘肃白水江国家级自然保护区林缘社区饲养犬只对大熊猫时空节律的影响

人类对于野生动物的影响复杂多样, 其中家养动物所产生的干扰往往被忽视, 例如保护区林缘社区饲养的家犬。半散放的家犬(Canis familiaris)进入野生动物栖息地, 对保护区内以大熊猫(Ailuropoda melanoleuca)为代表的野生动物可能产生重要影响。为明确家犬进入林区活动范围对大熊猫的影响, 本研究采用红外相机技术和GPS项圈无线追踪技术对甘肃白水江国家级自然保护区内家犬对大熊猫潜在栖息地范围和时间节律的影响进行研究, 利用MaxEnt模型对家犬活动范围及大熊猫潜在栖息地进行预测。结果表明: 甘肃白水江国家级自然保护区内大熊猫潜在栖息地面积为885.8 km², 约占保护区总面积的48.2%; 家犬活动面积为861.2 km², 约占保护区总面积的47.6%。家犬活动范围与大熊猫潜在栖息地重叠的面积约占保护区面积的28.2%, 且多集中在低海拔的常绿阔叶林。大熊猫在有家犬出现的位点和没有家犬出现的位点日活动节律具有显著差异。本研究揭示了家犬进入林区对大熊猫栖息地潜在影响的空间范围, 为保护区开展生物多样性管理提供了关键信息, 对于其他保护区具有借鉴意义。     

重组Bt伴胞晶体蛋白Cry5B对大熊猫西氏贝蛔虫的离体杀灭活性观察

大熊猫是中国特有的珍稀物种,西氏贝蛔虫是危害大熊猫最为严重的一种肠道寄生性线虫。针对目前长期药物驱虫导致的大熊猫西氏贝蛔虫耐药及生态污染问题,苏力菌(Bacillus thuringiensis,Bt)晶体蛋白Cry5B因其特异的线虫杀灭活性,是一种理想的新型抗蛔虫病药物候选。本研究拟通过原核表达方式产生Bt YBT-1518重组Cry5B蛋白,并评价其对大熊猫西氏贝蛔虫的离体杀灭活性。结果表明,Bt YBT-1518 Cry5B由1 246个氨基酸组成,分子量(MW)为139.889 kDa,包含Endotoxin_N、δ-Endotoxin_C、Endotoxin_C、Endotoxin_C2、Cry1Ac_D5结构域,与Bt PS86Q3晶体蛋白关系最近。重组Cry5B蛋白在IPTG浓度为1.4 mmol/L时表达量最大,表达于菌体上清液。离体杀灭活性实验表明,重组Cry5B蛋白的大熊猫西氏贝蛔虫抑杀效果具有显著的剂量依赖性,对肠道L4期幼虫第3天的ED₅₀值为14.5 μg/mL,第7天的ED₅₀值为0.16 μg/mL;但对成虫更敏感,仅作用2 d便可显著下降虫体活性,直至死亡,证实重组Cry5B蛋白对大熊猫蛔虫具有较强的毒杀作用。这些结果为后续论证Bt YBT-1518重组Cry5B蛋白可以作为一种新型、环保的抗大熊猫西氏贝蛔虫病药物提供了数据参考。     

大熊猫粪便乳酸菌的分离鉴定

大熊猫作为国家保护动物,其健康问题备受瞩目。为了维护大熊猫的肠道健康,本研究从大熊猫肠道内分离出适宜于大熊猫肠道环境的乳酸菌菌株,有望将其制成熊猫肠道微生物制剂,从而改善大熊猫肠道菌群环境。从雅安市宝兴县蜂桶寨自然保护区选取圈养与野生大熊猫的粪便,通过体外培养分离出9个菌株。分离菌株经过革兰氏染色镜检、过氧化氢产气、菌落形态观察等方法与技术初步鉴定为乳酸菌。对这9株乳酸菌进行耐酸试验、耐胆盐试验、抑菌能力试验和产酸能力等测试,筛选出了3个适应性较强,有望制成调节大熊猫肠道内环境平衡作用的微生态菌剂的菌株。16S rRNA基因序列分析表明:分离菌株J1、J2和J4分别为融合魏斯氏菌（Weissella confusa）,海氏肠球菌（Enterococcus heynei）和非解乳糖链球菌（Streptococcus alactolyticus）,有望被应用于大熊猫肠道微生态制剂的研究。     

2008年汶川地震后拐棍竹无性系种群的更新状况及影响因子

为揭示2008年汶川地震后大熊猫主食竹拐棍竹无性系种群的天然更新状况及影响因子,研究了3种不同地震干扰强度(强度、中度和对照)生境中拐棍竹的生长和发笋状况.结果表明:在3种生境中,拐棍竹存活笋的基径为中度干扰和对照生境显著大于强度干扰生境,存活笋的高度为对照＞中度干扰＞强度干扰.其发笋密度在3种生境中无显著差异,但强度和中度干扰生境中的存活笋密度显著大于对照,并且1年生和2年生竹密度与死亡竹密度之间呈极显著正相关.拐棍竹的发笋密度、存活笋密度、1年生、2年生和多年生竹密度之间均呈显著正相关,1年生和2年生竹密度与砾石和滑坡土壤盖度呈显著负相关,存活笋密度与郁闭度之间呈显著负相关.     

臭氧处理对圈养大熊猫食用竹笋的保鲜

<正>竹笋是大熊猫(Ailuropoda melanoleuca)最为喜爱的天然食物。竹笋相对于竹叶和竹茎含水量更丰富,粗纤维含量更低,适口性更好;大宗养分、微量元素、必需氨基酸等含量丰富(周昂等,1996;唐平等,1997;周材权等,1997),而丹宁等具有微毒性的次生代谢物含量却最少(赵晓红等,2001),更利于大熊猫对生活必需营养的吸收     

精料的蛋白质水平及能量浓度对亚成体大熊猫日粮消化率的影响

采用双因子交叉分组 (2× 2 )试验设计方案 ,选用 2只亚成体大熊猫进行 5期 (第 5期用常规日粮 )消化试验 ,考察精料的蛋白质水平与能量浓度对亚成体大熊猫日粮消化率的影响。结果表明 :精料蛋白质水平对粗蛋白、半纤维素、能量的消化率均产生显著影响 (P <0 0 5 ) ,对粗脂肪消化率产生极显著影响 (P <0 0 1) ,(相关系数分别为 0 7830、 0 76 18、 0 5 5 0 4、 0 6 72 3) ;精料能量浓度对无氮浸出物、中性洗涤纤维、能量的消化率产生显著影响 (P <0 0 5 ) ,对粗脂肪消化率产生极显著影响 (P <0 0 1) ,(相关系数分别为 0 5 5 6 9、0 6 0 4 7、0 5 0 5 2、 0 74 11)。对无氮浸出物、中性洗涤纤维、能量的消化率而言 ,该 2个因素互作效应显著 (P <0 0 5 )。1～ 4试验期 ,粗脂肪、半纤维素 ,1～ 5试验期 ,粗脂肪、半纤维素、中性洗涤纤维、纤维素、总能量等项消化率与 2个因素线性回归达到显著性水平 (α =0 0 5 ) (其中粗脂肪及 1～ 5期半纤维素达到极显著 ,α =0 0 1)。从多重比较结果看 ,除木质素外 ,各项消化率均以第 1期为最高 ,因此 ,日粮配方 1(CP2×GE2即CP 2 0 6 1%×GE 19 5 3MJ/kg)是优选配方     

首例圈养大熊猫产后出血的治疗及初生幼仔长途运输初探

中国保护大熊猫研究中心雅安碧峰峡基地的一只雌性大熊猫分娩后发生产后出血,采取促进子宫收缩、减少出血、利用抗菌素药物防止感染的原则对母兽进行治疗,4d后恢复正常。治疗期间取出两只初生幼仔,利用自制人工保温箱将幼仔成功地从雅安长途运回卧龙进行人工育幼;并对母兽进行育幼行为培训以保持母性行为,母兽康复后主动接受幼仔成功哺育成活。     

Application of ecological-niche factor analysis in habitat assessment of giant pandas

Ecological-niche factor analysis (ENFA) is a multivariate approach to study geographic distribution of species on a large scale with only “presence” data. It has been widely applied in many fields including wildlife management, habitat assessment and habitat prediction. In this paper, this approach was applied in habitat suitability assessment for giant pandas in Pingwu County, Sichuan Province, China. With “presence” data of giant pandas and remote sensing data, habitat suitability of pandas in this county was evaluated based on ENFA model, and spatial distribution pattern of nature reserves and conservation gaps were then evaluated. The results show that giant pandas in this county prefer high-elevation zones (> 2128 m) dominated by coniferous forest, and mixed coniferous and deciduous broadleaf forest, and avoid deciduous broadleaf forest and shrubs. Pandas avoid staying at habitats with human disturbances. Farmland is a major factor threatening panda habitat. Panda habitat is mainly distributed in north and west of Pingwu with a total area of 234033 hm², 106345hm² for suitable habitat and 127688 hm² for marginally suitable habitat). 3 nature reserves were located in Pingwu, covering over 49.2% of total suitable habitat and 45.6% of total marginally suitable habitat. Although 47.2% of panda habitat was in reserves under protection, connectivity between reserves was weak and a conservation gap existed in the north part of Pingwu. Thus, a new nature reserve in Baima and Mupi should be established to link the isolated habitats.     

大熊猫繁育障碍与染色体脆性位点的相关性研究

通过研究建立起适合大熊猫染色体脆性位点表达的BrdU诱导体系。以大熊猫外周血淋巴细胞为材料,通过较长时间培养（96h）,采用低浓度BrdU(10μg/ml）,短时间（4h）诱导,并结合复制带技术将大熊猫染色体脆性位点的高发生区段准确地定位在No.2和No.12号染色体着丝粒区域。经生物统计学分析发现,No.2和No.12号染色体脆性位点表达频率在个体中有明显差异,而且前者与大熊猫个体的子代存活率呈负相关（r=-0.772).研究结果提示,No.2染色体着丝粒处高效表达的脆性位点地大熊猫个体繁育及其后代的存活是不利的.