Freeze-branding beaver tails

Freeze-branding has proven useful in managing and researching a captive group of beaver (Castor canadensis) at the Minnesota Zoological Garden. Over 24 mo, 13 freeze-brands were applied to the tails of 11 beaver for varying application times. Permanence of brands increased with increasing distance from tail base. Because permanence of freeze-brands on cattle is influenced by skin thickness, the tail of a male beaver was horizontally sectioned into nine roughly equidistant segments, photographed to scale, and the epidermal/dermal thickness of the dorsal side of each section was measured to determine if skin thickness affected freeze-branding success in beaver. Thickness of the epidermal and dermal layers of the dorsal tail surface decreased 14-fold from tail base to tip. Based on our preliminary finding that freeze-brand permanence improved with decreased thickness of the epidermal/dermal layers of the tail, we recommend that beaver be freeze-branded for 25 s on the lower half of the tail for best results.     

开花期加拿大一枝黄花水浸提液对3种作物种子萌发和幼苗生长的影响

测定了入侵杂草加拿大一枝黄花（Solidago canadensis）开花期的茎、叶和花序水浸提液对辣椒(Capsicum annuum)、番茄(Lycoperiscum esculetum)、长梗白菜(Brassica chinensis var. communis)种子萌发和幼苗生长的影响。结果表明：（1）处于开花期的加拿大一枝黄花存在明显的化感作用,在25 mg·mL^-1时,对3种作物种子苗生长有促进作用,浸提液高于50 mg·mL^-1时,作物种子的萌发率和生长受到抑制,这种抑制作用随处理液浓度的提高而增强,在100 mg·mL^-1浓度处理下,甚至使作物种子失去活力;（2）加拿大一枝黄花叶和花序的水浸提液对种子萌发和生长的影响要大于其茎的浸提液;（3）在3种作物中,长梗白菜种子对加拿大一枝黄花水浸提液的敏感性最高。     

Genetic structure of California's elk: a legacy of extirpations,reintroductions, population expansions,and admixture

California, USA, is home to 3 subspecies of North American elk (Cervus canadensis): Roosevelt (C. c. roosevelti), Rocky Mountain (C. c. nelsoni), and tule (C. c. nannodes). Effective management requires a baseline understanding of each subspecies' range, admixture zones, and geographic patterns of genetic diversity. To address these questions, we genotyped 1,271 individual elk from California (n = 1,204) and reference populations of Rocky Mountain and Roosevelt elk from Nevada (n = 32) and Oregon (n = 35), USA. Using 19 polymorphic microsatellite loci, we detected admixture between Roosevelt and Rocky Mountain elk at a contact zone in northern California, and between Roosevelt and tule elk in north-coastal California and central-coastal California. We identified a genetically distinct population of Roosevelt elk in northwestern California, likely reflecting the remnant population that survived a large demographic decline from overhunting during the 1800s. Tule elk exhibited lower levels of heterozygosity (0.44 ± 0.03 [SD]) and allelic richness (2.9 ± 0.2) than Rocky Mountain (0.58 ± 0.05, 4.9 ± 0.4, respectively) and Roosevelt (0.50 ± 0.06, 4.4 ± 0.6, respectively) elk. Among tule elk populations, heterozygosity varied, with the lowest heterozygosity (0.23 ± 0.05) corresponding to the oldest enclosed herd used over the past century as a source of translocations. Among tule elk populations, genetic structure revealed several cases of successful and unsuccessful reintroduction or augmentation attempts. Results provide an essential baseline for future monitoring and decisions about harvest management, translocations to preserve genetic diversity, and landscape-level conservation planning to maintain, enhance, or obstruct connectivity of elk populations. Genome-wide sequencing and analyses are needed to quantify inbreeding absolutely and assess genetic load and the age of admixture where subspecies currently exchange genes.     

Isolation and characterization of microsatellite loci in the beaver (Castor canadensis)

We have isolated and characterized 10 microsatellite loci in the beaver (Castor canadensis). Sixty individuals from southern and central Illinois were screened at each locus. All loci exhibited moderate levels of polymorphism, ranging from five to 13 alleles per locus with average heterozygosity ranging from 0.317 to 0.867. Locus Cca5 deviated significantly from HWE (P < 0.001). The locus pair Cca4/Cca5 was shown to be in linkage disequilibrium in southern Illinois, but not in the central Illinois population. The remaining eight loci will be useful in investigations of mating and kinship patterns in beaver populations in Illinois.     

“黄莺花”与一枝黄花及其同属近缘种的形态比较

形态上与入侵杂草加拿大一枝黄花十分相似的“黄莺花”,近来作为鲜切花的配花走俏花卉市场,也引起了社会对其管理的高度关注。本文通过比较市售8个批次的“黄莺花”与35个入侵中国的加拿大一枝黄花种群、原产地的一枝黄花属2个种群以及一枝黄花的叶和花的11个形态学特征,并进行聚类分析。结果表明除第5批 “黄莺花”外的7个批次单独聚为一类,第5批次与35个入侵中国的加拿大一枝黄花种群聚为一大类,再结合加拿大的2个种群,而一枝黄花单独为一类。这充分说明“黄莺花”并非一枝黄花,而与入侵我国的加拿大一枝黄花各种群接近。进一步再与巨大一枝黄花和粗糙一枝黄花特征相比较分析,发现“黄莺花”与粗糙一枝黄花聚在一组,并进一步与入侵的加拿大一枝黄花相聚,加拿大1和2的种群更接近巨大一枝黄花,而一枝黄花单独成为一支。无论是加拿大一枝黄花、粗糙一枝黄花还是巨大一枝黄花都属于“加拿大一枝黄花复合种”。由此可以认为市售“黄莺花”属于外来入侵杂草加拿大一枝黄花的复合种。叶片长宽比、离基三出脉距叶基距离、表皮毛数的多少、缘花/盘花比等是“黄莺花”与该属其它类群分类鉴定的重要形态学特征性指标。     

土壤不同浓度铜对小飞蓬毒害及耐受性研究

通过对高Cu污染区(Ⅰ)、低Cu污染区(Ⅱ)和非污染区(Ⅲ)小飞蓬盆栽实验及生理生化指标分析,结果表明,生态型Ⅰ、Ⅱ、Ⅲ电导率均随着Cu浓度增加而增大,并且两者之间呈极显著正相关;叶绿素(a+b)含量随着Cu浓度增加呈极显著负相关;生态型Ⅰ的蛋白质和脯氨酸含量随着Cu浓度增加均先有所升高,然后又降低,而生态型Ⅱ、Ⅲ则一直呈现降低趋势.3种生态型小飞蓬体内SOD、POD、CAT酶活性在Cu胁迫下均有所提高,与对照相比,当Cu浓度为1200mg·kg^-1时,生态型Ⅰ的SOD、POD、CAT活性分别为194.1%、206.2%、1186%;Ⅱ的SOD、POD、CAT活性分别为170.1%、182.9%、1113%;Ⅲ的SOD、POD、CAT的活性分别为115.1%、155.4%、10.73%.对3种生态型小飞蓬的生理生化指标及酶活性分析表明,高Cu污染区小飞蓬的耐受性要强于低Cu污染区,两者又均强于非污染区小飞蓬,这3种生态型小飞蓬的耐受性呈现出了明显的种间差异.     

Bighorn Sheep Response to Road-Related Disturbances in Rocky Mountain National Park,Colorado

ABSTRACT Bighorn sheep (Ovis canadensis) use of Sheep Lakes mineral site, Rocky Mountain National Park, Colorado, USA, has decreased since 1996. Officials were concerned that human disturbance may have been contributing to this decline in use. We evaluated effects of vehicular traffic and other road-related disturbance on bighorn use of Sheep Lakes in the summers of 2002 and 2003. We found that the time and number of attempts required by bighorn to reach Sheep Lakes was positively related to the number of vehicles and people present at Sheep Lakes. Further, the number of bighorn individuals and groups attempting to visit Sheep Lakes were negatively affected by disturbance associated with the site. The number of vehicles recorded the hour before bighorn tried to access Sheep Lakes best predicted an animal's failure to cross Fall River Road and reach Sheep Lakes. We conclude that human and road-related disturbance at Sheep Lakes negatively affected bighorn use of the mineral site. Because Sheep Lakes may be important for bighorn sheep, especially for lamb production and survival, the negative influence of disturbance may compromise health and productivity of the Mummy Range bighorn sheep.     

红叶加拿大紫荆离体快繁技术研究

研究了基本培养基、生长调节剂配比、培养条件等对加拿大紫荆继代增殖的影响及不定根诱导和驯化移栽技术.结果表明:加拿大紫荆继代增殖宜选用DKW或WPM基本培养基附加40.0 g/L的白砂糖;生长素NAA较IBA、IAA更适于继代培养;间隔1～2代使用I.0 mg/L TDZ取代1.0～2.0 mg/L BA可明显提高繁殖系数和出苗量.27.5℃左右的温度有利于继代增殖,30℃高温、20℃低温及接种后黑暗培养均不适于生长.在1/2MS或1/2DKW附加1.0 mg/L IAA及25.0 g/L白砂糖的生根培养基上,生根率达80%,温室驯化移栽成活率达89%,可满足快繁要求.     

The influence of an electric field on growth and trace metal content in aquatic plants

It is known that both natural and artificial electric fields (EF) affect plants physiological parameters as well as germination, growth and yield. The present article describes results of a preliminary experiment on the impact of electric field on aquatic plants biogeochemistry. The objective of the present study was the assessment of the influence exerted by the electric field on growth and trace metals content of Elodea canadensis. In a laboratory experiment plants were exposed to the field intensity of 54?kV m^?1 for 7?days. The plants length was measured and the content of Fe, Mn, Ni, Pb, and Zn was determined using atomic absorption spectrometry (AAS). Results showed that the application of electric field slightly enhanced the growth of E. canadensis shoots. The content of Mn and Ni was significantly lower, and Pb and Zn significantly higher in plants exposed to the electric filed, while Fe content did not differ between control and EF treatment. This provides a rationale for further studies on biological effects of electric field in trace metal contaminated waters and application of an electrically enhanced phytoremediation.     

入侵植物加拿大一枝黄花对环境的生理适应性研究

 外来杂草已对我国的作物、果园、草坪、自然环境和生物多样性产生了严重危害。因此,对新传入的外来杂草开展生理生态学研究,对于预测它们在我国分布的潜在范围和生境特点有实践意义,了解新外来杂草对逆境条件的生理适应方面的知识,对它们的综合管理也是有益的。加拿大一枝黄花 (Solidago canadensis) 原产于北美,20世纪70年代作为花卉植物引入我国,现在是我国东南地区的一种常见外来杂草。本项工作测定了不同酸碱度、不同NaCl含量、不同质地的土壤、不同温度处理对加拿大一枝黄花植物体内游离脯氨酸、丙二醛、可溶性糖含量、过氧化物酶活性和过氧化物酶同工酶谱等生理指标的影响。结果表明：1）加拿大一枝黄花适生于偏酸、低NaCl浓度的土壤中;2）砂壤土、壤土比粘土更适于加拿大一枝黄花的生长;3）38 ℃的高温比5 ℃的低温对加拿大一枝黄花具有更大的损伤作用;4）加拿大一枝黄花地下根具有很强的无性繁殖能力。     

Integrating microsatellite and pedigree analyses to facilitate the captive management of the endangered Mississippi sandhill crane (Grus canadensis pulla)

The minimization of kinship in captive populations is usually achieved through the use of pedigree information. However, pedigree knowledge alone is not sufficient if pedigree information is missing, questionable, or when the founders of the captive population are related to one another. If this is the case, higher levels of inbreeding and lower levels of genetic diversity may be present in a captive population than those calculated by pedigree analyses alone. In this study, the genetic status of the critically endangered Mississippi sandhill crane (MSC) (Grus canadensis pulla) was analyzed using studbook data from the U.S. Fish and Wildlife Service managed captive breeding program as well as microsatellite DNA data. These analyses provided information on shared founder genotypes, allowing for refined analysis of genetic variation in the population, and the development of a new DNA-based studbook pedigree that will assist in the genetic management of the MSC population.     

中国鸟类新纪录——加拿大雁

<正>2014年12月21日,在天津市宁河区永定新河水域(39°15′24″N,117°26′2″E,海拔7 m)观察到4只加拿大雁(Branta canadensis)在此栖息觅食,同域亦有少量骨顶鸡(Fulica atra)、绿翅鸭(Anas crecca)、罗纹鸭(A.falcata)及赤膀鸭(A.strepera)在此活动。次日有观鸟者前往观察,未能再发现该群加拿大雁。本次观察到的加     

日本菟丝子（Cuscuta japonica）寄生对加拿大一枝黄花(Solidago canadensis)生理生态特性的影响

调查发现,野外有日本菟丝子(Cuscutajaponica)寄生于加拿大一枝黄花(Sotidago canadensis)植株的现象,被寄生的加拿大一枝黄花植株矮小,叶片枯黄,生长严重受阻.在实验控制条件下,观测了日本菟丝子寄生后加拿大一枝黄花生理生态特性的相关指标,并对寄主进行了解剖观察,探讨了应用日本菟丝子防除加拿大一枝黄花的可行性.结果表明:(1)日本菟丝子可以寄生于加拿大一枝黄花的茎及叶片,寄生根能够穿过加拿大一枝黄花表皮、皮层直至髓部,从寄主植株吸收水分和养分,使自身生物量得到增加,并严重影响了寄主的生长;(2)寄生50-60d后,被寄生植株最大光合速率只有对照的58.81%,而光合补偿点则为对照的153.39%;脯氨酸和丙二醛含量分别为对照的2.88和1.29倍,可溶性蛋白、可溶性总糖含量则分别下降了43.45%、44.47%;(3)金华地区,自然条件下生长的加拿大一枝黄花一般在9月中旬现蕾,10月中旬进入盛花期,而被寄生植株直到10月下旬才开始现蕾,花序长度不到正常植株的10%,当菟丝子生物量(干重)超过加拿大一枝黄花植株的13.14%时该植株不能开花结实.从实验结果看,日本菟丝子寄生可以严重影响加拿大一枝黄花的营养生长和开花结实.因此,利用日本菟丝子有望成为防治加拿大一枝黄花危害的一种辅助手段.     

Ten new polymorphic microsatellite loci for North American river otters (Lontra canadensis) and their utility in related mustelids

We describe 10 novel North American river otter (Lontra canadensis) polymorphic microsatellite loci. Individuals from two river drainages in New York were sampled, and the number of alleles per locus ranged from two to 12 (Drainage 1) and two to 10 (Drainage 2). Observed heterozygosities ranged from 0.21 to 0.83 (Drainage 1) and 0.20 to 0.80 (Drainage 2). Preliminary screening revealed that loci amplified in five other mustelids [Martes pennanti (n = 6), Martes fiona (n = 8), Mustela frenata (n = 8), Mustela erminea (n = 8) and Mustela vison (n = 5)].     

Survival of captive-born Ovis canadensis in North American zoos

The survival rate of North American bighorn sheep, Ovis canadensis, housed in several zoological gardens was analyzed. Complete herd histories, including birth and death data as well as causes of mortality, were collected from seven institutions. Lambs were divided into inbred and noninbred animals, with lambs being considered inbred if they had an inbreeding coefficient greater than zero. The rate of survival of inbred and noninbred lambs was compared using “survival equalling one year” and “survival equalling six months.” Another analysis compared the survival rate of male and female inbred lambs and male and female noninbred lambs. Age at death was also compared in inbred and noninbred lambs. The analysis of the data for the seven collections, located in various geographic areas and housing various subspecies, indicates that inbreeding depression is a mortality factor in the captive management of North American bighorn sheep. Therefore, long-term survival of captive or isolated wild populations will depend on maintaining genetic diversity within the herds through careful selection of breeding stock in captive populations and introduction of nonrelated animals into isolated wild populations.     

Development of polymorphic microsatellite loci for North American river otters (Lontra canadensis) and amplification in related Mustelids

In order to complement ecological research on native and reintroduced populations of the North American river otter (Lontra canadensis), we developed 10 polymorphic microsatellite loci that would permit us to evaluate population genetic structure and conduct fecal DNA analyses. The number of alleles per locus ranged from 3 to 14 and observed heterozygosity ranged from 0.23 to 0.68. Preliminary screening revealed that primers were polymorphic in a subset of other Mustelids.     

贵州省杨白纹潜蛾生物学初步研究

本文首次报道了杨白织潜蛾LeucopterasusinellaHerrich－Schaffer在贵州的发生危害情况,详细记述了杨白纹潜蛾各虫态的形态特征和生物学特性。在贵阳和铜仁地区,杨树受害株率达95％～100％,受害叶率达75％以上,受害叶每叶虫数3.6米以上,株虫口密度84．8头以上。该虫在铜仁地区1年发生5代,越冬代9月上旬化蛹,翌年4月上旬羽化。成虫寿命4～8天。卵块产于叶片正面贴近主脉或主侧脉处,卵历期2～5天,每卵块平均16卵粒。幼虫孵化时从卵壳底部咬孔潜入叶片组织取食叶肉,历期8～20天,幼虫老熟后咬破上表皮钻出,在被害叶片背面或吐丝下垂至下部叶片的叶背或下部主干与分技交界处的树皮裂缝中织“H”形茧化蛹。第一至第四代蛹历期为8～11天。本文还提出了该虫的防治方法。