Zinc toxicosis in a free-flying trumpeter swan (Cygnus buccinator)

A trumpeter swan (Cygnus buccinator) was observed near a mill pond in Picher, Oklahoma, USA. It became weakened and emaciated after about 1 mo, was captured with little resistance, and taken into captivity for medical care. Serum chemistry results were consistent with hepatic, renal, and muscular damage. Serum zinc concentration was elevated at 11.2 parts per million (ppm). The swan was treated for suspected heavy-metal poisoning, but died overnight. Gross postmortem findings were emaciation and pectoral muscle atrophy. Histopathologic lesions in the pancreas included mild diffuse disruption of acinar architecture, severe diffuse depletion or absence of zymogen granules, occasional apoptotic bodies in acinar epithelial cells, and mild interstitial and capsular fibrosis. Zinc concentration in pancreas was 3,200 ppm wet weight, and was similar to that reported in the pancreases of waterfowl known to be killed by zinc toxicity. Zinc concentrations in liver (154 ppm) and kidneys (145 ppm) also were elevated. Acute tubular necrosis of the collecting tubules of the kidneys was also possibly due to zinc toxicity. To the authors' knowledge, this is the first confirmed case of zinc poisoning in a trumpeter swan associated with mining wastes.     

Characterization of microsatellite loci isolated in trumpeter swan (Cygnus buccinator)

Primers for 16 microsatellite loci were developed for the trumpeter swan (Cygnus buccinator), a species recovering from a recent population bottleneck. In a screen of 158 individuals, the 16 loci were found to have levels of variability ranging from two to seven alleles. No loci were found to be linked, although two loci repeatedly revealed significant departures from Hardy–Weinberg equilibrium. Amplification in the closely related tundra swan (Cygnus columbianus) was successful for all except one locus. These microsatellite loci will be applicable for population genetic analyses and ultimately aid in management efforts.     

Mute swan (Cygnus olor) winter distribution and numerical trends over a 16-year period (1987/1988–2002/2003) in France

The numbers of mute swans (Cygnus olor) at 98 wetland locations in France were monitored monthly during the winter (December–February) for 16 years by a national network of observers as part of a broader national wildfowl monitoring scheme. Log-linear Poisson regressions with TRIM software were used to estimate missing counts and produce national numbers and indices. These corrected indices were in turn used to calculate an average annual rate of change and the associated confidence interval that subsequently enabled the computation of a cumulated (global) rate of change and associated confidence interval. The latter were interpreted to classify the numerical trends over the whole period. For the six wetlands with the largest numbers of mute swans, average numbers of swans were also compared between wetlands and months. General Linear Models were then used to test simultaneously for (1) differences between years and between wetlands for each month and (2) between years and between months separately for each of the six wetlands. The mute swan average annual rate of change was >7% for each month. The global rate of variation corresponded to a “strong increase” after TRIM analyses. This result strongly supports the necessity of maintaining both national and international monitoring schemes in order to be able to quickly detect major increases in swan numbers at specific sites, particularly where increasing numbers may result in a conflict with farmers or in inter-specific competition with other waterbirds and/or represent a possible sanitary/public health hazard due to the potential for swans to carry avian influenza viruses.     

Artificial incubation of trumpeter swan eggs: Selected factors affecting hatchability

Eggs collected from captive trumpeter swans (Cygnus buccinator) in 1993 (n = 33) and 1994 (n = 42) were artificially incubated with careful monitoring to identify factors contributing to the low hatch success reported by the Ontario Trumpeter Swan Restoration Program. Fertility was > 80% in both years, whereas hatch success of fertile eggs was 14.3% (n = 4) of 28 eggs in 1993 and 37.1% (n = 13) of 35 eggs in 1994. Necropsy of non‐viable eggs indicated a high incidence of embryonic mortality during early and late incubation. Early embryonic mortality was associated with egg storage times exceeding 7 days (P < 0.05) and bacterial contamination of eggs (P < 0.01). Late mortality was associated with (P < 0.001) increased weight loss during incubation period and may have resulted from incubator temperature and humidity fluctuations. We established patterns of weight loss for eggs and determined that hatched eggs lost 11–15% of initial mass and that weight loss >15% resulted in embryo mortality. Results from this study indicate that collection and handling of eggs before incubation and precise control of the incubator environment are critical to hatchability of eggs. Zoo Biol 18:403–414, 1999. © 1999 Wiley‐Liss, Inc.     

Die überwinterungsknospen des Krausen Laichkrauts (Potamogeton crispus) als Nahrung für den H?ckerschwan (Cygnus olor) auf dem Federsee

Summary In the highly eutrophicated, shallow Lake Federsee no submersed macrophytes grew, until 1982 a waste water pipeline around the lake was put in operation. In 1983Potamogeton crispus began to colonize the lake and its abundance increased from year to year. The growth cycle, however, remained very short and the macrophyte always died off between the end of June and the middle of July, after having developed large numbers of resting buds. Simultaneous with the increasing canopies ofPotamogeton a rise of Mute Swans in summer and autumn was observed, and because of the absence ofPotamogeton and other new food plants it was suggested that at this time the bird mainly feeds on the resting buds ofPotamogeton. This was confirmed by investigation of excrements, which sometimes consisted mainly of remnants of resting buds. Therefore it is supposed that Mute Swans essentially affect the recolonization of the lake byPotamogeton crispus and by this way also slow down the reestablishment of a diverse flora and fauna.     

基于卫星跟踪大天鹅春季迁徙时间及其影响因素

候鸟春季迁徙时间与其能否顺利完成迁徙过程,以及对繁殖地的成功选择和繁殖成效密切相关,通过对大天鹅越冬地和停歇地的春季迁徙时间选择原因及其影响因素进行分析,有助于深入理解候鸟春季迁徙时间策略和栖息地保护状况。2015年2月和12月,在河南三门峡湿地捕捉了60只越冬大天鹅并佩戴卫星跟踪器,获取了详细的大天鹅在越冬地和停歇地的春季迁徙时间等信息,并进一步分析了春季迁徙时间与气候因子的相关性。结果表明,大天鹅主要在夜间22：00-0：00和0：00-1：59迁离越冬地。大天鹅迁离越冬地的日期与温度呈显著性正相关,迁离时多选择顺风且风速较小的天气。大天鹅迁离越冬地后主要是在夜间飞行,而迁离停歇地后主要是在日间飞行。越冬地的温度越高,越有利于植物的生长,大天鹅可以快速地积累能量,提前开始春季迁徙。野外调查表明,内蒙古黄河中上游作为迁徙的重要停歇地,春季两岸捕鱼、农耕和放牧等为活动较多,因此大天鹅多选择在夜间觅食补充能量,在日间迁离。最后,针对黄河流域大天鹅栖息地的保护现状,提出了禁止经济开发项目、建立保护区和开展宣传教育等保护建议。     

Fitness consequences of hybridization between house sparrows (Passer domesticus) and tree sparrows (P. montanus)

Gene transfer may occur following hybridization between closely related species if hybrids are viable and able to breed with individuals of one or both of the parental species. House (Passer domesticus) and tree sparrows (P. montanus) occasionally hybridize and produce viable offspring. Previously, we concluded that male tree × house sparrow hybrids are most probably fertile based on the observation of a male F1 hybrid feeding the nestlings with a female house sparrow in two consecutive clutches. However, recent DNA analyses based on blood samples revealed that all nestlings (4) in the first clutch were sired by a neighbouring house sparrow male, whereas nestlings in the second clutch (2) were not blood sampled and most probably died before fledging. This indicates that extensive extra-pair fertilization confounded our previous conclusion, and indicates that social partnership and attending behaviour can be imprecise measures of paternity.     

Genetic differentiation of two distinct chemotypes of Ferula communis (Apiaceae) in Sardinia (Italy)

The giant fennel, Ferula communis L. (Apiaceae) is a circum-Mediterranean species responsible of severe haemorrhagic intoxication of livestock. Electrophoretic analysis of 14 putative enzyme loci was carried out to assess genetic differentiation among poisonous and non-poisonous chemotypes of F. communis in Sardinia. Genetic structuring characterises all the five populations examined. However, differentiation was higher between poisonous and non-poisonous populations (P<0.00001), and was independent from geographic distances, suggesting a reduced gene flow between the two chemotypes.     

High-Resolution Genetic and Physical Mapping of Modifier-of-deafwaddler (mdfw) and Waltzer (Cdh23)

Modifier-of-deafwaddler (mdfw) and waltzer (Cdh23^v) are loci on mouse chromosome 10 encoding factors that are essential for the function of auditory hair cells. The BALB/cByJ-specific mdfw allele encodes a necessary and sufficient modifier that induces progressive early onset hearing loss in CBy-dfw^2J heterozygotes. Recessive mutations in the waltzer locus result in circling behavior and congenital deafness. In this report we present a high-resolution integrated genetic and physical map of mdfw and Cdh23^v. Our genetic analyses localize mdfw between markers D10Mit60 and 148M13T7 within a 1.01-cM region. The Cdh23^v critical interval is fully contained within the mdfw region and localizes between markers 146O23T7 and 148M13T7 within a 0.35-cM interval that is represented in an ≈500-kb BAC contig. Our data suggest that mdfw and Cdh23^v are allelic.     

杏鲍菇菌种遗传多态性的ISSR分析

采用ISSR(Inter-simple Sequence Repeat)分子标记技术并应用NTSYSpc 2.10e生物软件对20株杏鲍菇菌种进行遗传聚类分析。结果表明,从22条引物中筛选出11条扩增条带清晰、多态性好的ISSR引物,共获得74个ISSR标记位点,51个多态性位点,多态比率为68.92%,产物片段大小在100~5 000 bp之间。聚类分析发现,遗传相似系数在0.828时,20株杏鲍菇菌种分为4个类群,当遗传相似系数达到0.896时,分为12个类群,杏528寿与其他菌种的亲缘系数最远,具有独立的遗传体系。     

Temperature but not rainfall influences timing of breeding in a desert bird, the trumpeter finch ( Bucanetes githagineus )

Reproductive performance in birds depends on several factors, one of the most important being the time of breeding. Birds try to fit offspring birth and growth to peak vegetative production in order to assure fledgling survival. In arid environments, where weather conditions are often extreme, birds must face unpredictable abiotic conditions. This study uses a border population of the trumpeter finch (Bucanetes githagineus) as a model to test whether climate variables (rainfall and temperature) influence breeding parameters by comparing 2 years with very different weather. The study was carried out in the Tabernas desert (southeastern Spain) in 2004 and 2005. A comparison of laying dates in the 2 years shows a 40-day delay in the date of the first clutch in the coldest year (mean minimum temperature 3°C lower in 2005 than in 2004). However, once the breeding season started, the number of clutches, clutch size, duration of the incubation period, nestling phase, fledgling rates and productivity were similar. One likely explanation for this delay is that low temperatures did not allow the germination of Diplotaxis sp., a plant forming the bulk of the trumpeter finch diet during spring. Its absence could prevent onset of breeding, although other temperature-related factors could also be involved. Although rainfall has frequently been reported as a limiting factor for arid bird species, our 2-year study shows that temperature can also influence the breeding biology of arid bird species, by affecting its timing.     

Genetic and physical maps of Klebsiella aerogenes genes for histidine utilization (hut)

Summary Deletion derivatives of the hut-containing plasmid pCB101 were tested against point mutants defective in individual genes of the histidine utilization (hut) operons using a complementation/recombination assay. Location of the genes of the right operon, hutU and hutH, was confirmed by direct assay of the gene products, urocanase and histidase; location of the repressor gene was identified by measuring the ability of the plasmid-carried genes to repress the formation of histidase from a chromosomal location. The analysis of eight deletion plasmids unambiguously confirms the map order of the hut genes as hutI-G-C-U-H, and demonstrates that, in Klebsiella aerogenes, the hutU and hutH genes are transcribed from their own promoter. In addition, the genetic map of hut can be aligned with the restriction map of the hut DNA in plasmid pCB101. One of the deletion plasmids studied apparently encodes a defective histidase subunit that is trans-dominant to active histidase. Another deletion, which completely removes the left operon, hutIG, allows high level expression of the hutUH operon and thus overproduction of a toxic intermediate.     

Genetic monogamy in the Common Crossbill ( Loxia curvirostra )

Extrapair paternity seems to be common in socially monogamous passerines, but the genetic mating system of most species is currently unknown. Here, we report the first study of paternity in the socially monogamous Common Crossbill (Loxia curvirostra). We found no evidence of extrapair paternity among 96 offspring in 34 examined broods. An upper 95% confidence limit of 3.1% suggests that extrapair fertilizations were truly infrequent in our study population. Common Crossbills thus seem to represent an exception to the rule of extrapair mating among socially monogamous passerine bird species. A potentially important selective pressure preventing promiscuity in Common Crossbills is the harsh environmental conditions experienced during breeding at wintertime, which may increase the importance of paternal care and limit the time available for seeking extrapair copulations.     

Genetic impacts of Anacapa deer mice reintroductions following rat eradication

The Anacapa deer mouse is an endemic subspecies that inhabits Anacapa Island, part of Channel Islands National Park, California. We used mitochondrial DNA cytochrome c oxidase subunit II gene (COII) and 10 microsatellite loci to evaluate the levels of genetic differentiation and variation in ~1400 Anacapa deer mice sampled before and for 4 years after a black rat (Rattus rattus) eradication campaign that included trapping, captive holding and reintroduction of deer mice. Both mitochondrial and microsatellite analyses indicated significant differentiation between Anacapa deer mice and mainland mice, and genetic variability of mainland mice was significantly higher than Anacapa mice even prior to reintroduction. Bayesian cluster analysis and Principal Coordinates Analysis indicated that East, Middle and West Anacapa mice were genetically differentiated from each other, but translocation of mice among islands resulted in the East population becoming less distinct as a result of management. Levels of heterozygosity were similar before and after management. However, numerous private alleles in the founder populations were not observed after reintroduction and shifts in allele frequencies occurred, indicating that the reintroduced populations experienced substantial genetic drift. Surprisingly, two mitochondrial haplotypes observed in an earlier study of Anacapa deer mice were lost in the 20 years prior to the rat eradication program, leaving only a single haplotype in Anacapa deer mice. This study demonstrates how genetic monitoring can help to understand the re-establishment of endemic species after the eradication of invasive species and to evaluate the effectiveness of the management strategies employed.     

Breeding and management of the common trumpeter (Psophia crepitans)

The breeding biology and management of three wild-caught adult Common trumpeters (one male and two females) was documented at the Woodland Park Zoological Gardens, Seattle, from April, 1984 to August, 1986. A total of 27 eggs were laid, and eight young survived to fledging. Both sexes exhibited crane-like dances during courtship, but the male appeared to perform these behaviors more frequently and with greater intensity than the females. Courtship feeding and allo-preening also occurred. Nests consisted of simple scrapes on the ground, but the birds had no opportunity to rest in trees or other elevated sites. Clutches contained two or three eggs, and the incubation period was aproximately 28 days. Although the breeding pair was generally aggressive toward the second female, all three adults participated in incubation and in caring for the young. Parental behavior consisted of brooding, allopreening, and feeding. The male preened and fed one chick significantly more often than either of the females. Trumpeter chicks were highly precocial, but grew relatively slowly, reaching 50% of adult weight by 45 to 50 days of age. Trumpeters are difficult to maintain and breed in captivity and appear to be susceptible to mycotic diseases, such as aspergillosis. Changes in the social composition of captive groups may result in improved breeding.     

Genetic analysis and mapping of gene fzp ( t ) controlling spikelet differentiation in rice

A mutant of spikelet differentiation in rice called frizzle panicle (fzp) was discovered in the progeny of a cross between Oryza sativa ssp. indica cv. V20B and cv. Hua1B. The mutant exhibits normal plant morphology but has apparently fewer tillers. The most striking change in fzp is that its spikelet differentiation is completely blocked, with unlimited subsequent rachis branches generated from the positions where spikelets normally develop in wild-type plants. Genetic analysis suggests that fzp is controlled by a single recessive gene, which is temporarily named fzp(t). Based on its mutant phenotype, fzp(t) represents a key gene controlling spikelet differentiation. Some F₂ mutant plants derived from various genetic background appeared as the “middle type”, suggesting that the action of fzp(t) is influenced by the presence of redundant, modifier or interactive genes. By using simple sequence repeat (SSR) markers and bulked segregant analysis (BSA) method, fzp(t) gene was mapped in the terminal region of the long arm of chromosome 7, with RM172 and RM248 on one side, 3.2 cM and 6.4 cM from fzp(t), and RM18 and RM234 on the other side, 23.1 cM and 26.3 cM from fzp(t), respectively. These results will facilitate the positional cloning and function studies of the gene.     

水位波动对洞庭湖越冬小天鹅家域的影响

洞庭湖是小天鹅在我国的重要越冬地之一,为探讨洞庭湖水位变动对越冬小天鹅活动的影响,本研究于2014-2015年利用卫星跟踪技术对洞庭湖自然保护区18只越冬小天鹅活动轨迹进行跟踪,采用最小凸多边形（MCP）和核心密度估计（KDE）方法估算了越冬中、后期不同水位条件下小天鹅的家域。同时,基于MODIS遥感数据提取洞庭湖水体面积、计算水体淹没时间指数（STI）,进而开展了水位与家域关系、栖息地选择模式等方面的分析和探讨。结果表明：水位对小天鹅家域起制约作用,随着水位上升小天鹅家域范围会明显减小;越冬期间小天鹅喜好在空间相邻的浅水和草地综合性区域活动,食物资源分布和可获得性是小天鹅活动区发生改变的主要原因。     

异叶泽兰的遗传多样性和居群历史动态研究

异叶泽兰属于菊科泽兰属,是该属分布海拔相对较高的植物,分布在青藏高原东部和横断山海拔1700～3000 m的地区.该文利用ycf6-psbM和rpl32-trnL两个叶绿体DNA(cpDNA)片段以及核DNA片段ITS(nITS)作为分子标记,研究了异叶泽兰的遗传多样性及其分布特征,探讨了其居群历史动态.结果表明:(1...