Mitochondrial DNA analysis reveals hidden genetic diversity in captive populations of the threatened American crocodile (Crocodylus acutus) in Colombia

Identification of units within species worthy of separate management consideration is an important area within conservation. Mitochondrial DNA (mtDNA) surveys can potentially contribute to this by identifying phylogenetic and population structure below the species level. The American crocodile (Crocodylus acutus) is broadly distributed throughout the Neotropics. Its numbers have been reduced severely with the species threatened throughout much of its distribution. In Colombia, the release of individuals from commercial captive populations has emerged as a possible conservation strategy that could contribute to species recovery. However, no studies have addressed levels of genetic differentiation or diversity within C. acutus in Colombia, thus complicating conservation and management decisions. Here, sequence variation was studied in mtDNA cytochrome b and cytochrome oxidase I gene sequences in three Colombian captive populations of C. acutus. Two distinct lineages were identified: C. acutus‐I, corresponding to haplotypes from Colombia and closely related Central American haplotypes; and C. acutus‐II, corresponding to all remaining haplotypes from Colombia. Comparison with findings from other studies indicates the presence of a single “northern” lineage (corresponding to C. acutus‐I) distributed from North America (southern Florida), through Central America and into northern South America. The absence of C. acutus‐II haplotypes from North and Central America indicates that the C. acutus‐II lineage probably represents a separate South American lineage. There appears to be sufficient divergence between lineages to suggest that they could represent two distinct evolutionary units. We suggest that this differentiation needs to be recognized for conservation purposes because it clearly contributes to the overall genetic diversity of the species. All Colombian captive populations included in this study contained a mixture of representatives of both lineages. As such, we recommend against the use of captive‐bred individuals for conservation strategies until further genetic information is available.     

环境因子对笼养朱鹮自然繁殖的影响

2004年3~7月,在陕西省洋县对人工饲养条件下朱鹮(Nipponia nippon)的自然繁殖进行了研究。18对繁殖鸟的窝卵数平均为(3.10±0.54)枚,孵化率26.2%,育雏成功率64.7%。当笼舍面积低于某一阈值时,窝卵数与笼舍面积呈明显正相关(Pearson,r=0.591,P<0.01)。出壳数、出飞数均与巢距遮荫树的距离呈负相关(Pearson,r1=-0.674,P1<0.05;r2=-0.677,P2<0.05)。亲鸟的繁殖经验对繁殖成功率没有显著影响,营巢环境是影响自然繁殖成功率的重要因素。     

人工饲养长江江豚的同性性行为和自慰行为

雌雄性之间的性行为对鲸类的生存和繁衍有着极其重要的意义。然而不具有繁殖功能的同性性行为和自慰行为在多种鲸类中存在。因此对鲸类非繁殖性性行为研究,将有助于深入认识该物种性行为特点和规律,并解决室内饲养可能存在的问题以及促进可控性人工繁殖的成功。本研究以人工饲养的7头长江江豚为研究对象,定义并描述了14种性行为。其中,同性之间的性行为定义为同性性行为,雌雄个体单独的性行为定义为自慰行为。雄性同性性行为发现于所有定义的性行为中,但雌性同性性行为仅在7种性行为中观察到。同性性行为（3633次）占总性行为（5563次）的65.31%,自慰行为（254次）占4.57%。同性性行为中,雄性之间的同性性行为（3438次,94.63%）远多于雌性同性性行为（195次,5.37%）。两头有父子关系的江豚（阿福和淘淘）之间的雄性同性性行为最多（1921次,55.88%）,雄性江豚之间的同性性行为可能存在结盟竞争关系或教育练习作用。两头青少年雌豚（F7和F9）之间的同性性行为最活跃（117次,60.00%）,雌性江豚之间的同性性行为很可能具有结伴交流的功能。     

红腹锦鸡的饲养繁殖与雏鸟生长发育

对红腹锦鸡的饲养繁殖与生长发育进行了研究和讨论。4～5月为产卵期,驯化当年能产少量卵,第2年每窝卵12～13枚,产卵期21～28d。家鸡代孵孵化期为21d,雌鸟自然孵化23d。最佳孵化方式为电孵卵器孵化,其次为雌鸟自然孵化。记述并统计分析了孵化过程中卵重、气室的变化以及体重及尾羽生长情况。体重及尾羽生长呈“S”形生长,前后期较慢,中期生长较快。     

Within-group differences in captive Diana monkey (Cercopithecus diana diana) behaviour

This case study examines the activity budgets of captive Diana monkeys (Cercopithecus diana diana) and discusses results in the context of what is known regarding captive and wild-type behaviour in this species and other guenons. The activities of a family group of Diana monkeys (two parents and four offspring) housed at Edinburgh Zoo, UK, were quantified using a 5-min interval scan sampling technique. The 5100 observation points collected showed that the subjects spent the largest proportion of their time observing (approx. 46%), followed by feeding (approx. 15%), playing (approx. 11%), mutual grooming (approx. 8%) and resting (approx. 7%). The daily activity budgets for each of the subjects were tallied and, at the end of the 10-day observation period, used to produce a data matrix consisting of nine behaviour variables per subject. Clear among-individual differences in activity were identified with canonical discriminant function analysis. This multivariate approach illustrated how the combined behaviours of the parent male were distinct from those of the rest of the family group. Within the remainder of the group, the three youngest offspring displayed similar activity budgets, whereas the overall behaviour of the eldest offspring (a female) was between that of its siblings and her mother.     

A comparative study of mechanisms of surfactant inhibition

Pulmonary surfactant spreads to the hydrated air-lung interface and reduces the surface tension to a very small value. This function fails in acute respiratory distress syndrome (ARDS) and the surface tension stays high. Dysfunction has been attributed to competition for the air-lung interface between plasma proteins and surfactant or, alternatively, to ARDS-specific alterations of the molecular profile of surfactant. Here, we compared the two mechanisms in vitro, to assess their potential role in causing respiratory distress. Albumin and fibrinogen exposure at or above blood level concentrations served as the models for testing competitive adsorption. An elevated level of cholesterol was chosen as a known adverse change in the molecular profile of surfactant in ARDS. Bovine lipid extract surfactant (BLES) was spread from a small bolus of a concentrated suspension (27 mg/ml) to the air-water interface in a captive bubble surfactometer (CBS) and the bubble volume was cyclically reduced and increased to assess surface activity of the spread material. Concentrations of inhibitors and the concentration and spreading method of pulmonary surfactant were chosen in an attempt to reproduce the exposure of surfactant to inhibitors in the lung. Under these conditions, neither serum albumin nor fibrinogen was persistently inhibitory and normal near-zero minimum surface tension values were obtained after a small number of cycles. In contrast, inhibition by an increased level of cholesterol persisted even after extensive cycling. These results suggest that in ARDS, competitive adsorption may not sufficiently explain high surface tension, and that disruption of the surfactant film needs to be given causal consideration.     

圈养马麝发情交配后期的日活动格局

2001年1月,对46只圈养马麝进行了行为取样,记录了四种行为状态,站立及运动,摄食,反刍,静卧。区分性别和年龄组,比较各组在发情后期的活动格局。在发情末期,马麝呈现多高峰的日活动节律,清晨的活动高峰不明显,故而包含于持续时间极长（07：00－14：30时）的上午活动高峰,另具黄昏（16：30－18：00）时和午夜（21：00－00：30时）活动高峰。发情后期,马麝的活动节律主要受圈养条件,气温和生理状态的影响,摄食高峰的初次出现与喂饲时间有关,在喂锔前后发生反刍高峰,这是对饲料限量投放的一种适应;为适应冬季夜间的低气温,马麝在夜间趋向于静卧,而在较暖的昼间活动,以减少热量消耗,马麝雌体的发情交配状态影响其活动性,已交配受孕的雌体活动性降低。雄体的活动格局也受年龄和近期交配经历的影响。     

白尾梢虹雉国内首次人工饲养繁殖成功

探讨了白尾梢虹雉人工引种的环境,管理,育雏,雏鸟羽毛生长等过程。     

实验室条件下达乌尔黄鼠的越冬繁殖

达乌尔黄鼠（Spermophilusdauricus）是国内研究冬眠生理学的主要模式动物,且日益为医学研究所关注。实验室条件下繁殖种群具有明确生活史特征,是相关研究的理想对象,但以往研究中,达乌尔黄鼠实验室条件下繁殖成功率及后代成活率均很低。本研究通过采取丰富饲料种类、雄性出眠后的暖温暂养、“双笼配对”等措施,对实验室条件下越冬达乌尔黄鼠进行配对,从21对动物中成功繁殖出18窝子代,繁殖成功率85.7 %。78只子代饲养至3月龄,仍有67只存活,存活率为85.9 %。通过本实验,得出改进达乌尔黄鼠实验室条件下繁殖的主要措施如下：（1）繁殖期母鼠及发育期幼鼠,除饲喂标准大鼠饲料外,适量添加幼犬粮、胡萝卜,以补充营养;（2）出眠的雄性达乌尔黄鼠放入18℃房间暂养2周,有助于其性腺发育,促进繁殖成功;（3）“双笼配对”能有效地降低外界干扰,减少动物的杀婴行为。       

降低圈养大熊猫排粘液频率的措施初探

大熊猫(Ailuropoda melanoleuca)是中国特有的珍稀动物,在其整个消化道内膜上,都分布有丰富的粘液腺。在野外,这些粘液腺的分泌物包裹于大熊猫摄食的竹茎、竹叶和竹笋表面而排出体外;圈养条件下,常常见到这些分泌物积聚到一定数量而成团排出,这即被称为大熊猫的排粘液现象(王平