圈养大熊猫的繁殖特性和生命表

通过对最大的大熊猫(Ailuropoda melanoleuca)圈养种群——中国保护大熊猫研究中心的圈养种群的研究,总结了圈养大熊猫的繁殖生物学特性,编制了大熊猫的生命表。大熊猫是季节性繁殖的动物,每年春季3～4月发情交配,8月(30.49%)和9月(48.88%)产仔,每胎平均产仔1.5只,圈养繁殖大熊猫的雌雄比为1.11。大熊猫的妊娠期和幼兽的初生体重变化很大,分别平均为139.8天和142.6g。性成熟的年龄,雌性是5.7±1.1岁,雄性是5.8±0.58岁。根据圈养大熊猫的生命表计算出圈养种群的净增长率R0为0.209,世代周期T为9.187年,内禀增长率r为-0.170,周期增长率λ为0.844。     

人工饲养下大熊猫繁殖生态的一些观察

我园人工饲养大熊猫已有27年历史,但从事人工饲养下的繁殖研究起步较晚,现就我园几年来人工饲养下大熊猫繁殖生态的一些观察叙述如下:大熊猫的年龄结构与性表现年龄:重庆动物园现饲养大熊猫8只,年龄分别为1至27周岁,雄性2只,雌性6只。年龄在4.5至15岁间的雌性熊猫3只,具有繁殖潜力。(其中2只已有生育,1只于1986年初开始发情,另3只年龄为1岁、2岁和27岁)。性表现的年龄与徐启明报道基本一致,但本园所繁殖3胎的生育年龄分别始于9岁和12岁,看来有性表现不等于具备繁殖能力,故可不必急于实施人工授精。人工饲养下的发情(持续)时间:雌性大熊猫在…     

野生雄性黄山短尾猴性行为季节性变化同步性(英文)

季节性繁殖是非人灵长类动物的普遍特征,而野生雄性个体的性行为季节性变化特点仍有待研究。该研究于2005年10月至2006年9月对黄山短尾猴鱼鳞坑YA2群5只成年雄性个体进行全年观察,以期探讨雄性黄山短尾猴性行为季节性变化特征。结果表明:繁殖季节交配行为和性动机行为(性追赶,做鬼脸和性检查)频次显著高于非繁殖季节,季节性差异显著。成年雄性个体交配行为和性动机行为季节性变化呈现显著同步性。该研究为进一步阐明短尾猴和同属季节性繁殖非人灵长类动物的雄性竞争和雄性策略提供理论依据。     

大熊猫人工授精的研究

繁殖大熊猫的目的是圈养种群的自我维持和保持遗传多样性。由于圈养种群中有自然交配能力的雄兽很少 ,人工授精则成为有效的遗传管理的重要手段。本研究的目的是确定单纯人工授精的效率。 1 998年至 2 0 0 0年期间 ,在中国保护大熊猫研究中心 ,对 7只大熊猫进行了人工授精 (每只连续 2d) ,精液通过人工采精方法从 6只不同的雄兽中获得 ,使用鲜精、冷藏精液和冻精多种方法进行人工授精。 6只雄兽的精液平均值是 :采精量 3.3±0 .5ml;精子密度 1 ,42 9.8± 2 35 .4× 1 0 6/ml;活力 81 .7± 2 .1 % ;运动状态 ( 0～ 5 ,5 =最好 )3 1± 0 .1 ;精子正常率 79 3± 9.2 %。对 7只大熊猫进行的 1 4次人工授精中 ,使用的精液体积为 2 4± 0 3ml;活力是 73.5± 2 .9% ;运动状态为 2 .5± 0 .1 ;每次人工授精总活动精子数是 684.2± 1 1 8.2× 1 0 6。 7只大熊猫有 4只受孕 ( 5 7.1 % ) ,共产 5仔。平均孕娠期 1 31 .5±9.7d ,每胎平均 1 .3± 0 .3仔。同时 ,运用自然交配与人工授精相结合的方法 ,进行了 1 8只次实验 ,成功 1 2只次 ,产仔 2 0只 ,繁殖成功率为 66.7%。本研究结果表明 ,人工授精能有效地使不能自然交配的雄性大熊猫参与繁殖 ,提高繁殖率 ,增加圈养大熊猫的遗传多样性。     

圈养雄性大熊猫尿中睾酮激素水平的测定

本文对圈养的两只雄性大熊猫尿中睾酮激素进行了测定与比较,结果表明该老龄大熊猫"菲菲"与壮年大熊猫"川川"在同一时期内尿中睾酮激素含量基本处于相同水平,两者没有显著差异.由此可见老龄雄性大熊猫"菲菲"仍具有繁殖能力.     

大熊猫精浆中谷草转氨酶活性影响因素的初步探讨

在2004年度大熊猫繁殖季节(2～5月),对5只不同年龄雄性大熊猫的精浆中谷草转氨酶(GOT)活性进行测定,并初步探讨其含量高低的影响因素。结果显示:大熊猫精浆的GOT平均活性为194.89±77.40IU/100mL,GOT含量高低与精子活力呈极显著负相关(r=-0.66,P<0.01);随着年龄增加,GOT活性有升高趋势;在繁殖季节,GOT有下降趋势。     

不同配种方式对大熊猫产仔效果的影响

１９８７－１９９３年,我国人工圈养的大熊猫先后有３１只雌性受配１０８只次,产仔胎,获幼仔４５只。有１６只雄性参加配种,其中７只能进行自然交配,９只没有自然交配能力。从３只雄性采出的良好精液,能使雌怀孕产仔,怀孕率为１９．１２％。在雄性自然交恿前后再给雌兽化人工授精,能提高雌兽怀孕产仔效果,来自不同山系大熊猫的繁殖能力有不同程序的差异,尤以岷山山系大熊猫的繁殖效果较差。     

高原鼠兔褪黑素受体在下丘脑-垂体-性腺轴中的表达分析

褪黑素在季节性繁殖动物的生殖细胞发育与性腺功能调控中发挥重要作用,然而褪黑素如何通过下丘脑-垂体-性腺（HPG）轴实现其调控功能目前仍不清楚。因此,本研究选取典型的长日照动物——高原鼠兔（Ochotona curzoniae）作为研究对象,使用酶联免疫吸附法测定繁殖期与非繁殖期雌雄鼠兔的血清褪黑素水平昼夜变化,利用实时荧光定量PCR分析褪黑素受体基因Mtnr1a与Mtnr1b在下丘脑、垂体与性腺中的表达水平,并通过免疫荧光染色进一步确认两种受体在性腺不同类型细胞中的定位。结果显示,非繁殖期雄性鼠兔的血清褪黑素含量始终高于繁殖期,且呈现不同的昼夜变化模式;雌性鼠兔的血清褪黑素含量远低于雄性鼠兔,且在繁殖期与非繁殖期并不存在显著差异。Mtnr1a与Mtnr1b在下丘脑、垂体与性腺中均有表达,雄性鼠兔在下丘脑与垂体中表现出繁殖期与非繁殖期基因表达的显著差异,而雌性鼠兔基因表达的差异主要出现在垂体与性腺中。两种受体蛋白在雄性性腺生殖细胞和支持细胞中均有分布,但MTNR1A更局限于精原细胞内,MTNR1B则在管腔内生殖细胞中表达。雌性性腺中MTNR1A在卵母细胞胞质内有表达,但更集中表达于颗粒细胞;MTNR1B在颗粒细胞以及卵母细胞核质内均有表达,且在生长卵泡的卵泡膜细胞中呈现高表达。以上结果表明,褪黑素调控雌雄高原鼠兔季节性繁殖的模式并不相同,其作用不仅限于通过下丘脑-垂体-性腺轴的间接调控,也可能通过性腺内靶向受体直接影响生殖细胞与体细胞命运。     

北京动物园大熊猫繁殖记录

北京动物园在三十年中,共繁殖大熊猫28胎（其中双胎18次）,产仔46只,成活21只,成活率为45．65％,为大熊猫的迁地保护作出了杰出的贡献。1963年第一次在人工饲养下自然繁殖成功大熊猫“明明”;1978年第一次用人工授精方法繁殖成功大熊猫“元晶”;1980年第一次以纯超低温保存的大熊猫冷冻精液人工授精成功产下二仔;1987年第一次在人工饲养下繁殖出子三代;1990年第一次实现不同地理位置的大熊猫自然交配繁殖成功幼仔“亚庆”;1992年第一次繁殖成功大熊猫人工授精第三代幼仔“京京”;1992年第一次以人工授精繁殖长大的雄性大熊猫自然交配成功繁殖“永明”和“永亮”;1992～1993年第一次以人工哺育的方法使未食母乳的大熊猫幼仔“永亮”成活;1993年第一次达到1992年所产的3仔全部成活,成活率为100％。     

动物园大熊猫繁殖观察

大熊猫(Ailuropoda melanoleuca)数量稀少,分布地区狭窄,为我国特有珍稀动物。为挽救这种濒危动物,除了加强对产区的保护外,对动物园大熊猫的繁殖进行研究,也是非常必要的。我园1头雌性大熊猫产于四川王朗自然保护区。1974年进园,1976年春初次发情(5岁),因缺配偶多年未进行繁殖。1981—1982年,该熊猫在四川成都动物园与1头雄性大熊猫完成交配,分娩于庐山。1981年生1胎,产2仔,仔未得初乳第三天死亡。1982年生1     

基于红外相机技术对佛坪国家级自然保护区 大熊猫季节性空间分布与活动模式的研究

2015年1月至2017年12月,在陕西佛坪国家级自然保护区海拔1 200~2 500 m的57条大熊猫(Ailuropodamelanoleuca)活动频繁的巡护样线上,布设130台红外相机。累计红外相机有效工作日100 685 d,共拍摄到大熊猫有效独立照片1 831张。将红外相机拍摄的有效照片和相机工作日依据不同竹种类型及保护站归类,对大熊猫季节性空间分布与活动模式进行研究。结果表明:(1)大熊猫春季活动最为频繁,在巴山木竹(Bashania fargesii)林和秦岭箭竹(Fargesia qinlingensis)林中相对多度分别是2.89和3.72;其次是冬季,在巴山木竹林和秦岭箭竹林中的相对多度分别是2.95和2.74。3月份是其活动高峰,巴山木竹林和秦岭箭竹林中的相对多度指数都是最高;11、12和1月份,大熊猫在巴山木竹林中相对多度指数高于秦岭箭竹林;2至10月份,大熊猫在秦岭箭竹林中的相对多度指数都要高于巴山木竹林。(2)大熊猫在佛坪保护区各个保护站均有分布,且存在季节性空间分布差异。三官庙和西河保护站全年的12个月都能够捕获到大熊猫的身影,是大熊猫分布相对多度最高的两个区域,大古坪、岳坝和龙潭子3个保护站海拔较低,大熊猫主要集中在冬春季节活动;凉风垭保护站海拔较高,主要分布的是秦岭箭竹林,大熊猫主要在夏季活动。(3)干扰活动主要包括采集、放牧、旅游、家犬活动和监测5种类型。干扰活动类型在各个保护站存在差异,且多为零星干扰,对大熊猫的活动和分布存在一定影响。本研究较为全面地调查了佛坪国家级自然保护区大熊猫季节性活动动态和区域性分布状况,调查结果可为后期的保护管理提供有效的参考依据。     

荒漠沙蜥松果体褪黑激素含量的季节性变化

应用高效液相色谱法(HPLC)-UV检测了不同季节荒漠沙蜥(Phrynocephalus przewalskii)松果体内褪黑激素的含量.结果显示,其高峰值发生在春季,为1 017±209 pg/pineal.低峰值出现在冬季(实验室内冬眠,2～4℃),为355±68.5 pg/pineal,秋季的含量(735±133.7 pg/pineal)高于夏季的含量(597±94.9 pg/pineal).表明荒漠沙蜥松果体褪黑激素含量呈现明显的年周期节律并与光周期和生殖周期的年节律基本相符.     

Modeling activity patterns of wildlife using time‐series analysis

The study of wildlife activity patterns is an effective approach to understanding fundamental ecological and evolutionary processes. However, traditional statistical approaches used to conduct quantitative analysis have thus far had limited success in revealing underlying mechanisms driving activity patterns. Here, we combine wavelet analysis, a type of frequency‐based time‐series analysis, with high‐resolution activity data from accelerometers embedded in GPS collars to explore the effects of internal states (e.g., pregnancy) and external factors (e.g., seasonal dynamics of resources and weather) on activity patterns of the endangered giant panda (Ailuropoda melanoleuca). Giant pandas exhibited higher frequency cycles during the winter when resources (e.g., water and forage) were relatively poor, as well as during spring, which includes the giant panda's mating season. During the summer and autumn when resources were abundant, pandas exhibited a regular activity pattern with activity peaks every 24 hr. A pregnant individual showed distinct differences in her activity pattern from other giant pandas for several months following parturition. These results indicate that animals adjust activity cycles to adapt to seasonal variation of the resources and unique physiological periods. Wavelet coherency analysis also verified the synchronization of giant panda activity level with air temperature and solar radiation at the 24‐hr band. Our study also shows that wavelet analysis is an effective tool for analyzing high‐resolution activity pattern data and its relationship to internal and external states, an approach that has the potential to inform wildlife conservation and management across species.     

Microsatellite variability reveals the necessity for genetic input from wild giant pandas (Ailuropoda melanoleuca) into the captive population

Recent success in breeding giant pandas in captivity has encouraged panda conservationists to believe that the ex situ population is ready to serve as a source for supporting the wild population. In this study, we used 11 microsatellite DNA markers to assess the amount and distribution of genetic variability present in the two largest captive populations (Chengdu Research Base of Giant Panda Breeding, Sichuan Province and the China Research and Conservation Center for the Giant Panda at Wolong, Sichuan Province). The data were compared with those samples from wild pandas living in two key giant panda nature reserves (Baoxing Nature Reserve and Wanglang Nature Reserve). The results show that the captive populations have retained lower levels of allelic diversity and heterozygosity compared to isolated wild populations. However, low inbreeding coefficients indicate that captive populations are under careful genetic management. Excessive heterozygosity suggests that the two captive populations have experienced a genetic bottleneck, presumably caused by founder effects. Moreover, evidence of increased genetic divergence demonstrates restricted breeding options within facilities. Based on these results, we conclude that the genetic diversity in the captive populations is not optimal. Introduction of genetic materials from wild pandas and improved exchange of genetic materials among institutions will be necessary for the captive pandas to be representative of the wild populations.     

雄性小熊猫粪便中睾酮水平的变化与繁殖周期的关系

1999 年12 月至2000 年9 月, 使用放射免疫分析法, 测定了成都动物园和成都大熊猫繁育研究基地的4 只雄性小熊猫粪样中睾酮水平变化情况, 同时对其行为进行了观察。研究结果表明, 雄性粪样中睾酮水平在繁殖期(12 月～3 月) 显著高于非繁殖期(4 月～9 月) (P < 0.01) , 且睾酮水平变化与繁殖行为密切相关。在非繁殖期,雄性小熊猫的睾酮水平处于基础的较低水平时, 其繁殖行为如蹭阴、舔阴、舔标记物和咩叫等几乎没有发生或很少发生; 而在繁殖期, 雄性小熊猫的睾酮水平明显升高, 这些繁殖行为频繁发生。以上结果说明, 睾酮是调节雄性小熊猫繁殖行为季节性变化的生理因子。     

秦岭大熊猫冬春季节对巴山木竹竹林生长指标的选择

2004~2005年冬季的12月、1月和春季的4月、5月,在秦岭山系南坡佛坪自然保护区内就大熊猫对构成其主要栖息地和食物来源的巴山木竹竹林的选择进行研究后的结果表明:在冬季,大熊猫栖息地多为幼竹与死竹比例基本持平、密度稳定的巴山木竹竹林,主要取食老竹;在春季,大熊猫更偏好选择竹子密度和盖度略低、竹子粗壮高大、幼竹与竹笋比例高的竹林活动,主要取食幼竹。大熊猫春季栖息地幼竹比例通常高过死竹比例,竹林密度处于增长期。竹林进入发笋期后,稀疏、高大的竹林下的粗大竹笋成为大熊猫的主要食物来源。     

Effects of melatonin implants on plasma concentrations of testosterone, thyroxine and prolactin in the male silver fox (Vulpes vulpes)

Melatonin administration in the form of slow-release implants advanced breeding activity in silver fox males when treatment began in June. Plasma testosterone concentrations were significantly higher in treated animals than in controls from September to November, whereas in February and March they were significantly lower. Plasma prolactin concentrations were significantly reduced immediately following melatonin treatment in June but increased to greater levels than control values and 'peaked' after 7 months. This 'peak' was associated with a rapid decrease in testosterone secretion. The normal seasonal spring rise in prolactin secretion was prevented by melatonin administration. Thyroxine values decreased and were significantly lower after 2 months of melatonin treatment.     

Seasonality and the melatonin signal in relation to age as correlated to the sexual cycle of the one-humped male camel (Camelus dromedarius)

Heparinized blood samples were taken from male immature and mature camels of the Sha'alah breed, housed at the University Animal farm, during the rutting and non-rutting period. Other blood samples were also collected from camels slaughtered at defined seasons (summer, autumn, winter and spring) and from the Buraydah slaughter-house. In addition, specimens from the testes were also taken to confirm the difference between the immature and the mature animals during the non-rutting and rutting seasons. The plasma obtained from the collected blood samples was used for estimation of the following hormones, Melatonin (MLT), Follicle Stimulating Hormone (FSH), Leutinizing Hormone (LH), Testosterone and Prolactin (PRL) using the radioimmunoassay technique. Specimens of testes tissue were fixed in calcium formol, processed for histological examination using standard procedures and stained with H&E. The results clearly differentiated the samples as immature and mature during the non-rutting and rutting seasons. Commercially available human radioimmunoassay (RIA) kits for MLT, FSH, LH, testosterone and PRL were adapted for quantitation of these hormones in serum from the one-humped camel (Camelus dromedarius). Serum samples from 40 camels were assayed in order to determine possible differences between various groups in the concentrations of MLT, FSH, LH, testosterone and PRL in these animals. Among the camels, serum concentrations of melatonin, FSH, LH, testosterone and prolactin reflected age and seasonal differences. Immature camels had overall significantly lower levels in MLT, FSH, LH, testosterone and PRL. Mean FSH and LH levels from confirmed non-rutting (sexually inactive) camels were 0.22 ± 0.08 and 0.37 ± 0.18 ng/mL, respectively. Although rutting (sexually active) camels had higher FSH and LH levels, the differences were not statistically significant (P less than 0.07). Our observations indicate that these RIAs can reliably detect serum MLT, FSH, LH, testosterone and PLT from camels and represent the first quantitation of melatonin in Camilidae in correlation with FSH, LH, testosterone and prolactin.     

圈养大熊猫群体间的基因流状况分析

圈养群体的遗传管理一个非常重要的手段就是实现不同群体间的基因交流.为了全面评估大熊猫圈养群体间的基因流状况,本研究以卧龙中国大熊猫保护中心的31只圈养大熊猫(简称卧龙群体)和成都大熊猫繁育研究基地与楼观台陕西省珍稀野生动物抢救饲养研究中心的37只圈养大熊猫(简称成都群体,其中楼观台1只)为研究对象,以7个大熊猫微卫星位点为分子标记,发现卧龙群体和成都群体间的遗传分化水平很低(Fst=0.041,P=0.001);尽管整个圈养群体的近交程度较低(Fis=0.026),但是成都群体的近交系数(Fis=0.045)远高于卧龙群体的近交系数(Fis=0.002);谱系分析、贝叶斯分析和系统进化法分析均显示,这两个群体间存在着基因流,但是这种基因流是单向的.此结果提示各个大熊猫饲养单位之间必须实现更多的合作,将大熊猫群体作为一个管理单元进行管理,从而实现更多的基因流.     

Melatonin administration increased plasminogen activator activity in ram spermatozoa

The aim of the present study was to investigate the effect of melatonin on plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) in ram spermatozoa and seminal plasma, in correlation with changes in blood testosterone. Melatonin implants (18 mg) were placed subcutaneously in sixteen Chios rams in autumn and spring. Semen samples for spectrophotometrical assays were collected 36 h before the implantation of melatonin and thereafter once a week, for 17 weeks. Blood samples for testosterone assay (RIA) were collected 8h before implantation (one sample/30 min x 7.5 h) and thereafter every 15 days for 105 days after implantation. For each ram, six parameters of testosterone were estimated: mean value, basal level, number of peaks, peak amplitude, peak duration and mean testosterone concentration during peaks. Melatonin implantation during autumn induced an increase in PAA and t-PAI in spermatozoa; melatonin implantation in spring induced an additional increase in u-PAI and PI; no change in PAA, PAI or PI was found in seminal plasma, during autumn or spring. The melatonin-induced increase of PAA, PAI and PI in spermatozoa was in positive correlation with the increase of testosterone mean value, basal level and number of peaks; the increase of testosterone parameters was greater in autumn compared to spring. Changes of PAA, PAI and PI of spermatozoa, under the influence of melatonin, might indicate changes in the fertilizing ability of spermatozoa, since plasminogen activators and their inhibitors are present on the plasma and the outer acrosomal membrane of spermatozoa and are released during the acrosome reaction.