人工养殖的扬子鳄适应自然环境的能力

为了复壮扬子鳄野生种群数量,实施养殖扬子鳄放归自然是重要途径之一.通过对人工养殖扬子鳄进行野外放归的试验研究,以探明其在野外环境下活动情况和适应能力.2007年6～11月,采用无线电遥测跟踪、望远镜观察和夜间辅助灯光望远镜观察等方法,对健康的4条5.5年龄和3条2.5年龄的人工养殖扬子鳄在自然环境下活动情况进行观察;在2008和2009年的5月,将这些鳄重捕后测量它们的大小并察看生长情况.结果显示:扬子鳄的释放初期经历了过渡期和争夺领域期2个阶段,20天后处于不同的区域内,具领域特征和营建洞穴行为,能够安全越冬;逐渐恢复野生习性,自我保护的警惕性提高,逃避威胁的能力加强;小龄鳄生长明显,大龄鳄没有明显生长,这与它们所处环境的食物种类有关;鳄性成熟后,能够成功繁殖.总之,人工养殖扬子鳄能够适应相应的自然环境,能够正常生活、生存和繁衍.     

泰国Khao Yai国家公园豹猫和云豹的生态和保护

于1997年10月到1999年10月在泰国KhaoYai国家公园对两种同域分布的物种（即豹猫和云豹）进行了研究。使用带诱饵的陷阱捕捉了这些动物,进行麻醉,确定了性别、年龄,并戴上了无线电项圈,对6只雌性豹猫和4只雄性豹猫进行了1—18个月的无线电追踪。豹猫在干旱季节的利用区域大于雨季,雄性利用的区域大于雌性。在夜间和晨昏时节,豹猫活动增加,但是并没有节律性活动。所有豹猫个体在旱季和雨季的活动都相似,但雄性个体的白天活动多于雌性。豹猫的行走距离有性别差异但是没有季节差异;其食物以鼠类为主。分别对1只雌性云豹和1只雄性云豹进行了17个月和7个月的无线电追踪,雌性个体的活动面积为39．4km^2,而雄性个体活动面积为42．2km^2,核心区都是2．9km2。云豹对半绿林的使用大于其它类型的植被,在晨昏和夜间的活动增加,其活动无节律。     

扬子鳄雌鳄血糖季节性变化的研究

本文用葡萄糖氧化酶-过氧化物酶法处理雌性成年扬子鳄的血浆,经光电比色,测得不同季节中雌性成年扬子鳄血糖值,发现其血糖值有着季节性变化。3月底出眠前,血糖水平降至一年中的最低点(71.32±7.09mg/100ml),出眠后血糖迅速上升,至4月26日达全年最高峰(209.72±33.00mg/100ml),随后降至108.78±23.50mg/100ml的基准水平左右,人眠前其血糖水平又出现一低一矮的峰值。这种季节性变化与扬子鳄的生理周期和环境温度变化有一定联系。     

扬子鳄FoxO1基因CDS序列的克隆及其在初孵鳄性腺组织的时空表达规律

研究以初孵扬子鳄(Alligator sinensis)性腺组织为实验材料, 开展Forkhead box家族蛋白-1(FoxO1)基因CDS区克隆和序列特征分析。利用免疫组织化学检测其在胃、肠和肺脏等组织中的表达谱, 结合免疫荧光(IF)、RT-PCR和Western Blot探讨其在不同出壳后日龄(17日龄、63日龄和96日龄)雌性扬子鳄性腺组织中的时空表达规律, 探讨其在雌性扬子鳄性腺发育过程中的生物学功能。研究成功克隆获得FoxO1基因长度为1941 bp的完整编码区及646个预测编码氨基酸序列。与其他物种间进行同源性比对和构建进化树分析发现, 扬子鳄FoxO1基因与鸟类的亲缘关系相较中华鳖(Pelodiscus sinensis)和原矛头蝮(Protobothrops mucrosquamatus)等爬行动物更近。在其他脊椎动物中, 哺乳动物、硬骨鱼和两栖物种也各自聚类称为子群, 表明FoxO1兼具功能保守性和种间特异性; 免疫组织化学结果表明FoxO1在初孵鳄性腺复合体、肺、胃和肠中均有表达, 免疫荧光结果表明17日龄性腺组织中的FoxO1主要表达于肾上腺和中肾区但在皮质部呈微弱表达, 在63日龄性腺皮质部表达逐渐上调且呈无规则随机分布, 在96日龄性腺皮质部中卵母细胞发育程度更高的位置呈强表达; RT-PCR结果表明不同时期扬子鳄性腺组织FoxO1基因mRNA表达量差异不显著, Western Blot结果显示性腺组织中的FoxO1表达量呈先上升后下降的变化模式, 表现为63日龄FoxO1基因表达量显著高于17日龄和96日龄, 相关结果对于丰富扬子鳄卵子发生调控机制提供了重要的研究参考。     

人工驯养下扬子鳄的生长规律

研究结果表明扬子鳄在饲养条件下的生长具有一定的规律性。饲养群体中,5龄以前的鳄生长速率较快,其中在2龄前生长速率最快,在5龄至7龄间生长速率明显减慢;鳄体长与体重之间呈正相关,两者在体长小于50cm时呈直线相关,体长大于50cm时呈曲线相关。不同性别的扬子鳄年生长状况不同,从5龄开始雌雄鳄体重出现显著差异,雄鳄重于雌鳄;从6龄开始雌雄鳄在体长方面的生长速率出现差异,雄鳄生长明显快于雌鳄;达到10龄后,雌雄鳄在体长和体重方面的增长均明显减慢,达到15龄时两者的体形已相差悬殊,雄性大于雌性。由von Berta-lanffy生长模型分析,雌鳄达到25龄而雄鳄达到35龄后,各自的体长几乎停止生长,雌鳄平均最大体长为173cm,雄鳄平均最大体长为219cm。在人工越冬下,除第一次越冬外,扬子鳄在越冬室内的冬眠中体况无明显变化,体能明显消耗出现在户外冬眠过程中。本研究为扬子鳄的科学化饲养提供理论依据。     

扬子鳄生活习性与环境温度的关系

１９８８￣１９９５年,每天观察扬子鳄的生活行为,并测量气、水温度,经过多年的重复观测,发现扬子鳄的生活习性与环境温度间存在着紧密关系：每年１０月下旬至次年４月底,鳄处于冬眠期,旬平均温度幅度在３￣１８℃间在至１０月下旬为采食期,旬平均温度幅度在２０￣３２℃间;５月下旬至９月下旬鳄处于繁殖期,旬平均温度幅度在２４￣３２℃间。据此总结出扬子鳄年生活周期循环规律图,并认为扬子鳄的生活及生理机能受气候温度     

夏秋两季饲养条件下扬子鳄的行为谱和活动节律初步研究

2003年夏秋两季(7-11月间),采用扫描取样法和目标动物取样法,对饲养条件下扬子鳄的个体行为和活动 节律进行了研究。结果表明:夏秋两季饲养条件下扬子鳄的个体行为主要包括休息行为(水中休息、陆地休息、晒 太阳、挠痒、打哈欠、伸懒腰);运动行为(游泳、潜水、爬行、摆尾);摄食行为(摄食、漱口);冲突行为(打斗、对视);嬉 戏行为(嬉戏、堆积);吼叫行为;排泄行为等。 夏季,扬子鳄休息行为的时间最多,日变化规律显示:早晨6:00-7:00为休息高峰期;下午12:30-13:30为潜 水高峰期。秋季,用于晒太阳的时间最多,秋季早晨6:00-7:30为潜水高峰期,且一天中扬于鳄晒太阳活动出现三 次高峰即10:30-11:00,13:30-14:00,16:30-17:00。统计结果表明,夏秋两季潜水、晒太阳和休息3种个体行为差 异性较为显著。在30℃-36℃之间,扬子鳄潜水时间和温度之间呈线性关系。研究结果同时表明,长期人工饲养 对扬子鳄的某些弹性行为如摄食行为等产生了较大影响。在行为描述的基础上,对扬子鳄的有关行为机制进行了 探讨。而影响扬子鳄行为表达的生物因素主要包括年龄和食物资源;非生物因素主要包括空间和生境等。     

交配期扬子鳄合唱吼叫的集群作用及其生物学意义

吼叫是扬子鳄(Alligatorsinensis)经常发生的行为之一,而目前有关吼叫行为生物学意义的资料还很缺乏。本文通过对安徽省扬子鳄繁殖研究中心繁殖区内扬子鳄吼叫行为的监测和观察发现,5-10月,扬子鳄常在水池边形成合唱吼叫(即两条以上鳄在同一时间段内一起吼叫);并且在交配期(6月份)吼叫声会引起四处分散栖息的个体向同一水体聚集,与非交配期相比具有明显的集群作用;交配期合唱吼叫具有6∶00-7∶00和11∶00-12∶00两个明显的高峰时间段,与其随后的交配高峰(夜间12∶00左右)都相差12h以上。分析表明,扬子鳄在交配期形成合唱吼叫的主要作用可能在于召集其它个体(包括雌性和雄性)形成集群,为集群后的水中寻找配偶和多次交配做准备.     

笼养藏猴交配行为的初步研究

本文对笼养藏猴交配活动的观察表明:1.Macaca thibetana属多次跨爬及单次跨爬射精兼而有之的类型,而非典型的单次跨爬射精型;2.在交配活动中,特别是在性伙伴的选择上,雌性和雄性一样起着积极的作用;3.M.thibetana雌性存在性干扰行为,并且雌性的社会地位可能受其交配活动影响。     

扬子鳄的越冬管理

扬子鳄(Ａｌｌｉｇａｔｏｒｓｉｎｅｎｓｉｓ)是我国特有的珍稀爬行动物。安徽省扬子鳄繁殖研究中心经过20年的发展,现有扬子鳄8000余条,是国内外驯养、繁殖扬子鳄的最大种群基地。冬眠是扬子鳄适应寒冷气候的一种生理现象,其越冬管理的好坏直接影响到幼鳄的成活率和成鳄的繁殖率,故其越冬技术一直很受重视,并不断得以完善,现将其总结,供引种扬子鳄饲养者参考。由于不同年龄扬子鳄的生理特点和管理要求不同,所以将扬子鳄的越冬管理分成当年孵出鳄、2-6龄鳄和成鳄3个年龄段来叙述。1　当年孵出鳄的越冬管理当年孵出的幼鳄,身体各器官的功能尚…     

AFLP Analysis of genetic variation on captive‐bred chinese alligators: an application to select individuals for release

The Chinese alligator (Alligator sinensis) is a critically endangered species in China. Wild populations of Chinese alligator are on the edge of extinction. Through a release program, some captive‐bred alligators will be selected and released into the wild to supplement and renew natural populations. The purpose of this study was to investigate the genetic variation of captive‐bred Chinese alligators by AFLP markers and to select individuals with maximally different genetic backgrounds for release. Forty‐three captive‐bred alligators of the second filial generation from the Anhui Research Center for Chinese Alligator Reproduction (ARCCAR) were surveyed using four primer combinations, yielding 117 AFLP markers. According to AFLP fingerprints, six samples had distinctly different band patterns compared to other samples. When the six samples were removed from the analysis, there were 19 monomorphic loci and 98 polymorphic loci yielding 84% polymorphic loci. Moreover, the genetic similarity (GS) among 37 samples varied from 0.13–0.97, and the average was 0.7503±0.0064 standard error (SE). When the six samples were included, the GS value among the 43 samples declined and varied from 0.06–0.97, and the average was 0.6523±0.0079 SE. Based on a cluster analysis using UPGMA, a dendrogram of the 43 alligators was constructed. According to the cluster analysis and gender of the 43 samples, eight Chinese alligators with very different genetic backgrounds were selected and suggested for release with two groups in the future. Zoo Biol 0:1–12, 2006. © 2006 Wiley‐Liss, Inc.     

野生扬子鳄种群动态变化及致危因素

1998—2003年,采用问卷调查、走访居民、夜间灯光照射计数等方法,对可能有野生扬子鳄(Alligator sinensis)分布的安徽省、浙江省和江苏省的45个地点进行了调查。结果发现：目前野生扬子鳄呈点状分布在至少23个地点,个体总数约120条,主要集中分布在安徽扬子鳄国家级自然保护区内。通过连续调查和对比分析表明：自20世纪50年代扬子鳄数量急剧下降(从5000—6000条下降为120条),但1998年至今其数量保持相对稳定(120条),种群的致危因素主要是栖息地破坏、人为捕杀、环境污染、自然灾害、繁殖力低等。在不同时期导致数量下降的因素不同：1950—1990年问,主要是由于栖息地丧失、人为捕杀等;目前的主要致危因素是缺乏适宜的自然栖息地,环境污染和遗传多样性丧失是潜在的致危因素。旱灾对野生扬子鳄生存的影响并不明显。     

野放前候选扬子鳄泄殖腔的细菌鉴定

扬子鳄(Alligator sinensis)是中国濒危的物种,野生鳄种群已濒临灭绝。通过放归工程,将挑选饲养鳄放养到野外去扩大野生种群。本文的研究目的是通过检测扬子鳄的健康状况为扬子鳄的筛选提供依据。从 25 条准备进行野放的扬子鳄泄殖腔中筛选出 13 种形态不同的菌株。应用细菌学和分子生物学方法,鉴定它们分别属于 6个属的 8 个种和一个未分类的菌;从扬子鳄生活的水体中筛选出 8 种形态不同的菌株,鉴定它们分别属于 1 个属的 4 个种。经分析,除了未分类的菌之外,从扬子鳄泄殖腔中分离得到的菌株都是非致病性的且不同于扬子鳄生活水体中分离的菌株,因此可以认为这些扬子鳄是健康的,可以野放。由于从标记为 AS12 的扬子鳄体内分离到一个分类地位尚未确定的菌,对它的生理生化特征进行了检测,但这种菌的致病性方面特征尚不清楚,建议不考虑野放标记为 AS12 的扬子鳄个体。     

Study on the current population and habitat of the wild Chinese alligator ( Al ligator sinensis )

A survey of wild Chinese Alligator was conducted from July to August 1999 and from August to September 2000 by direct counting after dark (20 z00pm) using headlamps or a 12v portable spotlight. At each site visited , the authors mapped the ponds using laser rangefinder and compass , characterized the physical nature of the ponds and vegetation , and conducted interviews with local residents. The location of all sites was recorded using a hand2held GPS. There are 26 sites in 5 counties that were surveyed where wild Chinese Alligators still exist in Anhui province , including 13 designated conservation sites of the National Chinese Alligator Reserve. The current wild alligator populations mainly exist in the best type of habitat , which totals 17.4 ha with estimated populations of 50.7 % in 1999 and 40.0 % in 2000. This can be compared with the other two types of habitat , which total 22. 0 ha and 19. 0 ha , with their estimated population numbers of 24.0 % in 1999 and 30.9 % in 2000 , and 25.3 % in 1999 and 29.1 % in 2000 respectively. The average ecological densities of the alligators in the two years were 1.3 ind. / ha and 1.8 ind. / ha , with an estimated population of 145 individuals. However , the population has been evidently divided into 18 isolated small local populations with different numbers of individuals. We suggest that habitat should be restored and captive-reared alligators should be reint roduced into the area to rebuild a viable population.     

野生扬子鳄种群及栖息地现状研究

1999年7～8月及2000年8～9月,利用GPS、激光测距仪等,采用夜间灯光照射计数方法,对 有野生扬子鳄(Alligator sinensis)存在的安徽省宣州、泾县、广德、郎溪、南陵等5 县市的26个地点进行了调查,包括扬子鳄国家级自然保护区的13个指定保护点。结果发现： 目前野生扬子鳄主要生存在第一类栖息地（1999年50.7%、2000年40.0%）,面积为17.38 hm²;其他两类栖息地的野生扬子鳄分布比率较小（各为1999年24.0%、2000年30.9%、1999 年25.3% 、2000年29.1%）,面积分别为22.04hm²、19.03hm²。两年的平均生态密度分别为1.28条/hm²和1.79条/hm²,野生扬子鳄种群数量为145条。其种群已明显分为至少18个数 量不等且相互隔离的地方种群。建议恢复足够大的栖息地,并放饲养鳄于其中以重新 建立有效野生种群。     

影响扬子鳄产蛋量的因素分析

1997～2006年对安徽省扬子鳄繁殖研究中心内的扬子鳄亲本、F1代和F2代繁殖鳄群体在冬眠环境条件、采食量、年龄等方面进行观察,对各代繁殖鳄的年产蛋数量进行统计。用SPSS11.0软件中的one-way ANOVA方法分析比较人工饲养鳄各代群体之间及人工饲养鳄与野生鳄群体之间年产蛋数量的变化关系,结果显示区域内扬子鳄所建造的洞穴数量和其所建造洞穴的质量决定着圈养鳄的冬眠质量,鳄的冬眠质量影响到鳄体内的性腺系统正常发育,最终影响扬子鳄次年能否参加产蛋;年采食量影响鳄的产蛋数量。通过第1、2、5年间产蛋量F值检验(F值=4.866,P=0.009<0.05),得出圈养条件下扬子鳄的产蛋数量是随着产龄的增加而呈增长的趋势。     

野生扬子鳄洞穴口的位置选择

1999年至 2 0 0 2年 7～ 10月内的 4个时段 ,在安徽扬子鳄国家级自然保护区内调查发现野生扬子鳄洞穴 4 0个 (现用 2 4个 ,遗弃 16个 )。对洞口的方向、隐蔽程度、距水面高度、与水源距离及与村落距离等 5个可能影响扬子鳄洞穴选择的环境变量做了测定。结果表明 :87 5 %的洞口在水面 0～ 0 5m及 <0m ,85 0 %距水源 <5m ,32 5 %朝北 ,72 5 %植被覆盖度≤ 70 % ,4 2 5 %距村落 <10 0m ;距水面高度、与水源距离、洞口方向和隐蔽程度的主成分贡献率依次降低 ,累计达 76 6 %。方便入水是洞口位置选择的主要因素     

Growth rates of Chinese and American alligators

Growth rates in two closely related species, Alligator mississippiensis (American alligator) and Alligator sinensis (Chinese alligator), were compared under identical conditions for at least 1 year after hatching. When hatched, Chinese alligators were approximately 2/3 the length and approximately 1/2 the weight of American alligator hatchlings. At the end of 1 year of growth in captivity in heated chambers, the Chinese alligators were approximately 1/2 as long and weighed approximately 1/10 as much as American alligator yearlings. When the animals were maintained at 31 degrees C, Chinese alligator food consumption and length gain rates dropped to near zero during autumn and winter and body weights decreased slightly, apparently in response to the change in day length. At constant temperature (31 degrees C), food consumption by American alligators remained high throughout the year. Length gain rates in American alligators decreased slowly as size increased, but were not affected by photoperiod. Daily weight gains in American alligators increased steadily throughout the year. In autumn, provision of artificial light for 18 h a day initially stimulated both length and weight gain in Chinese alligators, but did not affect growth in American alligators. Continuation of the artificial light regimen seemed to cause deleterious effects in the Chinese alligators after several months, however, so that animals exposed to the normal light cycle caught up to and then surpassed the extra-light group in size. Even after removal of the artificial light, it was several months before these extra-light animals reverted to a normal growth pattern. These findings may be of interest to those institutions engaged in captive growth programs intended to provide animals for reintroduction to the wild or to protected habitat.     

Nest Site Preference and Fidelity of Chinese Alligator(Alligator sinensis)

Oviparous female reptiles select nesting sites with optimal ecological factors that contribute to egg development. Chinese alligator(Alligator sinensis), an oviparous reptile, is a critically endangered crocodilian with temperature-dependent sex determination. Research on its nesting behavior may facilitate the protection of this species. In this study, we monitored nesting behavior over eight years. We compared selected frequency of nest sites, distance from nest site to water, height from nest site top to the water surface, distance from nest site to human activity region, and canopy density between nest sites on the island and bank. The results showed that 45 nest sites were used by female alligators over eight years and each site was selected from one to 10 times. The selected frequency of nest site occurrence on the island was higher than that on the bank(P 0.001). We observed that 88% of the individual alligators(15/17) showed different degrees of nest site fidelity. However, Chinese alligators might not always be loyal to only one nest site because of environmental changes or interspecific competition at nest sites. Our findings suggest that female alligators prefer to nest at island, which might be because of the nests on the island had a higher canopy density(P = 0.010) and were further from the human activity region(P 0.001) than those on the bank did. It would be beneficial to reduce human activities during the breeding season and protect the vegetation of Chinese alligator habitats in the future. of the beach(Ali et al., 2005; Kamel and Mrosovsky, 2005; Turkozan et al., 2012). Other species such as snakes and lizards select nest sites with more moist substrates, which significantly increases their body size at hatching(Brown and Shine, 2004; Reedy et al., 2013). Nest site preference may be maintained for one or more breeding seasons(Janzen and Morjan, 2001; Kamel et al., 2006). When female chose the same site or area during different years, it is called nest site fidelity(Switzer, 1993). This nest choice behavior may influence offspring survival(Lindeman, 1992) and nest site fidelity has been documented in numerous species such as birds(Lindberg and Sedinger, 1997), turtles(Mitrus, 2006; Walde et al., 2007), tuatara(Refsnider et al., 2010), and crocodilians(Elsey et al., 2008).Chinese alligator(Alligator sinensis) is a critically endangered freshwater crocodilian endemic to China(Thorbjarnarson and Wang, 1999). Recent investigations show that there are no more than 130 Chinese alligators     

老幼龄扬子鳄端粒相对长度的差异性分析

端粒（Telomere）是线性真核细胞染色体末端的一种结构,由高度重复的DNA序列和结合蛋白所构成。在脊椎动物中,端粒通常为富含TG简单重复序列（TFAGGG）,其生物学功能是完成染色体末端复制,使DNA免受不恰当的修复以及防止端一端融合和核酸外切酶的降解（Dreesen et al．,2007）。