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1.
Fifty cranes, consisting of 46 sandhill (Grus canadensis) and four whooping cranes (Grus americana), were studied. Eighteen sandhill cranes and the four whooping cranes were naturally infected with disseminated visceral coccidiosis (DVC). The remaining sandhill cranes were chicks experimentally infected with oocysts of Eimeria reichenowi and/or E. gruis; five chicks served as controls. There were no clinical signs attributed to respiratory infection. Necropsy of naturally infected adult birds revealed nodules in many organs, including the lung, air sacs, trachea and nares. Artificially infected sandhill cranes and the whooping crane chicks that died from DVC had congestion and consolidated areas in the lung with frothy fluid in the airways. Grossly visible nodules were observed from 10 days postinoculation. Granulomatous pneumonia and tracheitis were observed with light microscopy. Lesions were associated with merogonic and gametogonic stages of eimerian coccidia. Granulomas and granulomatous foci contained parasitized large mononuclear cells. Merogonic stages were seen in lymphoid cells by ultrastructural examination. Oocysts were observed in the trachea and bronchial mucosa and admixed with exudate in the airways, indicating that crane eimerians can complete their life cycle at these sites. Of the few eimeriid coccidia that have extraintestinal stages of development in birds and mammals, only the species in cranes complete their life cycle in both the digestive and respiratory tracts.  相似文献   

2.
Libyostrongylus is composed of 3 species, L. douglassii, L. dentatus, and L. magnus, which are differentiated based on the morphology of the adults worms. Of these, only the first 2 species have been described in Brazilian ostriches (Struthio camelus). There are very few citations regarding the occurrence of L. dentatus, having been reported only in North America and Brazil, while L. douglassii is distributed worldwide. Reports on differences in the localization of Libyostrongylus species inside the proventriculus are not available. Thirty proventriculi were collected and examined for the presence and location of the nematodes with the aid of a stereomicroscope. The collected parasites were conditioned separately, according to their sites of infection, in plates containing 0.09% saline solution. The worms were identified based on morphologic characters. All the examined proventriculi were parasitized by L. douglassii and L. dentatus. However, L. douglassii was observed under the koilin layer, while L. dentatus was inserted and attached in the koilin layer. Thus, the present study identifies different sites of infection by the 2 species of Libyostrongylus found in Brazil.  相似文献   

3.
Endoparasites detected in the black-bellied whistling duck (Dendrocygnaautumnalis) include one nasal mite, four nematodes, three trematodes, five cestodes, and two acanthocephalans. Each of these represents a new host record. Overall, 47% of the birds were parasitized with an average of 12 helminths per infected bird. Helminths were significantly more common in juveniles than in adults; more females than males were parasitized, but the difference was not statistically significant. No correlation existed between the parasite load and the physical condition of the host. Tissue damage in infected birds was minimal and limited to nematode cysts in the proventriculi. Parasite loads were light, apparently reflecting the food habits of the host.  相似文献   

4.
The enteric flora of captive whooping cranes (Grus americana) and sandhill cranes (Grus canadensis) has not been well described, despite its potential importance in the understanding of both the normal condition of the intestinal physiology of these animals and the altered colonization within disease states in these birds. Nineteen whooping cranes and 23 sandhill cranes housed currently at the Calgary Zoo or its affiliated Devonian Wildlife Conservation Centre (DWCC) in Calgary, Alberta were sampled from October 2004–February 2005 by collecting aerobic and anaerobic cloacal swabs from each bird. There were seven major groupings of bacteria isolated from both species of crane. Gram‐positive cocci, coliforms, and gram‐negative bacilli were the most prevalent types of bacteria isolated for both crane species, with Escherichia coli, Enterococcus faecalis, and Streptococcus Group D, not Enterococcus the bacterial species isolated most commonly. There was a significant difference in the average number of isolates per individual between the two crane species but no differences between age or gender categories within crane species. Campylobacter sp. were isolated from five whooping cranes. The potential zoonotic pathogen Campylobacter jejuni was isolated from one whooping crane and C. upsaliensis was isolated from a second. Three other isolates were unspeciated members of the Campylobacter genus and likely belong to a species undescribed previously. The evaluation of the enteric cloacal flora of whooping cranes and sandhill cranes illustrates that differences exist between these two closely related crane species, and highlights the potential implications these differences may have for current practices involving captive wildlife. Zoo Biol 0:1–13, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

5.
Landfill disposal of a fertilizer manufacturing waste product was associated with a die-off of gulls in New Hanover County, North Carolina. An estimated 250 herring and ring-billed gulls were found dead at the site following the initial disposal of this material. Chemical analyses revealed that the fertilizer waste contained predominately calcium (12.0 to 22.2%) and nitrite (3.0 to 15.2%). Contents of the proventriculi and gizzards of dead gulls also contained calcium (3.0 to 10.9%) and nitrite (1,730 ppm). Fertilizer waste administered orally to 16-day-old domestic turkeys resulted in acute, progressive signs of depression, respiratory distress, pallor, convulsions and death. The mean percentage methemoglobin in blood from convulsing turkeys (90.6) was significantly increased from that of normal control turkeys (3.6). The ante-mortem signs and increased blood methemoglobin concentrations in the experimental turkeys support the conclusion that the toxic principle in the fertilizer waste was nitrite, and that nitrite poisoning was the cause of the die-off of gulls.  相似文献   

6.
云贵高原黑颈鹤的种群数量和分布   总被引:8,自引:1,他引:7  
云贵高原有黑颈鹤的两个越冬区:(1)云南西部;(2)云南东北部和贵州西北部。这两个地区的黑颈鹤数量占全球种群的1/4至1/3。国际鹤类基金会与云南省林业厅于2001/2002年冬季在云贵高原联合对黑颈鹤进行了一次同步计数,本次调查覆盖了17个已知或潜在的黑颈鹤越冬地点,其中15个地点有黑颈鹤分布。在2002年1月18日和19日,分别记录到3261和3182只黑颈鹤。本调查还统计了灰鹤、斑头雁和赤麻鸭,数量分别为:灰鹤804和1158只;斑头雁1759和2978只;赤麻鸭3442和5444只。与1991/1992年冬季进行的调查结果相比,黑颈鹤在这一地区的数量增加了90%以上。  相似文献   

7.
8.
白鹤(Leucogeranus Leucogeranus)是国家Ⅰ级重点保护野生动物,唯一一种极度濒危(CR)鹤类,分布和种群数量是评估其濒危程度的重要参数。无人机调查作为目前生态学研究的一个重要调查方法,为查明白鹤的越冬分布、种群数量及幼鸟比例,于2022年1月使用地面监测结合无人机调查的方法在江西、山东、安徽、湖南、湖北等地的湖泊和农田中开展越冬白鹤调查。野外调查共记录白鹤5607只,网络信息检索在调查区域外的8个地点记录白鹤9只,合计记录越冬白鹤5616只。其中江西鄱阳湖记录到越冬白鹤4813只,占总数的85.7%,主要分布在康山垦殖场、五星垦殖场和成新垦殖场;山东黄河三角洲记录到越冬白鹤625只,占总数的11.1%。安徽、湖南、湖北分别记录到越冬白鹤34,63和72只。对部分群体的白鹤幼鸟数量进行统计,4680只白鹤中,记录到幼鸟674只,幼鸟比例为14.4%,其中湖南越冬白鹤幼鸟比例最高,达28.6%,山东越冬白鹤幼鸟比例最低,为11.5%。调查刷新了白鹤种群数量,证实了山东黄河三角洲是目前除江西鄱阳湖外最重要的白鹤越冬地,缓解了白鹤越冬期过度集中的压力。基于本研究结果,我们...  相似文献   

9.
The genetic diversity of the founders of an artificial population of the Siberian crane Grus leucogeranus Pallas (rare species of cranes) was characterized using 10 microsatellite loci. It was established that the allelic diversity (on average, 5.9 alleles per locus) and genic (H O = 0.739) diversity of the Siberian crane is rather high and comparable with the estimations for natural populations of different crane species. Genetic passportization of the birds (119 individuals) from the register of the Siberian crane International Studbook was carried out at the initial stage. The efficiency of genetic passportization for individual identification, identification of the origin, paternity analysis, and exclusion of inbreeding was demonstrated in Siberian cranes under natural mating and artificial insemination. Cases of natural reproduction in pairs of Siberian cranes imprinted to the human and continuous storage of spermatozoa in the female reproductive ducts were registered.  相似文献   

10.
There are few quantitative estimates of numbers of Africa's endangered grey crowned cranes (Balearica regulorum), yet conservation of this species will depend on such estimates. We used line-transect distance sampling on multiple 2-km segments of an existing road network to estimate the abundance of grey crowned cranes in a portion of the Ngorongoro Crater, Tanzania, during the wet (April) and dry (August) seasons of 2016. We analysed data from 106 transects on which we observed 174 groups of 1–61 cranes (median and mode = 2). Abundance and density estimates on the areas surveyed were best modelled without group size as a covariate and indicated that mean crane densities were significantly lower in the wet season (2.4/km2) than in the dry season (20.2 cranes/km2). Even based on survey areas of different size, minimum estimated numbers of cranes in the Crater (wet season: 108–133; dry season: 362–401) likely reflect the concentration of cranes in the nonbreeding (dry) season in the perennial wetlands of the Crater and reinforce the notion of the Crater being a key seasonal habitat for crane populations in northern Tanzania, as previously suggested in the literature.  相似文献   

11.
Pb and Cd concentrations in the habitat and preys of the red-crowned crane (i.e., reed rhizomes and three typical aquatic animal families (Perccottus glehni Dybowski, Carassius auratus Linnaeus, and Viviparidae)) were analyzed to examine the impact of these hazards on red-crowned cranes in northeastern China. Results indicated that Pb and Cd concentrations in the preys of the red-crowned cranes were elevated via food chain. Most of the detected Pb and Cd contents in the sediments were above the natural background level, ranging from 9.85 to 129.72 ppm and 1.23 to 10.63 ppm (dry weight), respectively. Cd geo-accumulation index at all sites were larger than 3, even reached 5.22, suggesting serious pollution in this region. Three common water animal families were detected to contain heavy metals, following the order of increasing concentrations: primary consumers (i.e., Viviparidae and Carassius auratus Linnaeus)?<?secondary consumers (i.e., Perccottus glehni Dybowski). Pb and Cd concentrations in the buffer zone are significantly higher than in the core area and being elevated in the food chain. The molten feathers of the red-crowned cranes showed the highest toxic metal concentrations of Pb (2.09 to 5.81 ppm) and Cd (1.42 to 3.06 ppm) compared with the feces produced by cranes and residual eggshell left by water fowls. Exceptionally high Pb and Cd concentrations in the cranes and their preys were thought to be associated with their habitat.  相似文献   

12.
近十年来鄱阳湖区越冬白鹤种群数量与分布   总被引:1,自引:0,他引:1  
1998—2010年,该研究采用地面同步调查法在鄱阳湖区64个湖泊开展了越冬白鹤种群监测。结果表明,鄱阳湖区分布有稳定的越冬白鹤种群,鄱阳湖区越冬白鹤种群数量年平均值为(3108±849)只,2002年冬季达到最大值4004只;从2003年开始鄱阳湖区越冬白鹤数量表现出一定的年际波动,但变化幅度较小。共有46个湖泊被记录到有白鹤活动。其中,达到全球白鹤种群数量1%标准以上的湖泊达25个;白鹤数量接近或超过全球白鹤种群数量的40%,即1280只个体以上的湖泊包括鄱阳湖国家级自然保护区内的大汊池、蚌湖和蚕豆湖,以及保护区外的南湖。自然保护区涵盖了越冬白鹤的主要聚集湖泊。分布在自然保护区内的白鹤占鄱阳湖区越冬白鹤种群总数量的(66±27.3)%。保护区外分布的白鹤数量虽然总体呈下降趋势,但仍分布有一定数量的个体。  相似文献   

13.
为探索圈养鹤类的血液生化指标差异,本研究对白鹤(Grus leucogeranus)、丹顶鹤(G.japonensis)、黑冠鹤(Balearica pavonina)、黑颈鹤(G.nigricollis)、灰冠鹤(B.regulorum)、蓝鹤(Anthropoides paradiseus)和白枕鹤(G.vipio)的10项血液生化指标(总胆固醇、甘油三酯、总蛋白、白蛋白、球蛋白等)进行统计分析,并与国际物种信息系统(ISIS)提供的数据进行比较。结果表明,1)不同鹤类之间总胆固醇差异显著,而甘油三酯和血糖没有显著性差异,除了黑冠鹤和灰冠鹤的总胆固醇以及蓝鹤的血糖外,其余鹤类的常值均高于ISIS的平均值。2)不同鹤类之间的总蛋白、球蛋白和白蛋白的浓度差异显著,但总蛋白、球蛋白和白蛋白均在ISIS的正常范围内。3)不同鹤类间肌酐和尿酸不具有显著性差异,其中尿酸低于ISIS平均值,但仅尿素氮差异显著。不同鹤类之间血液生化指标存在差异,与圈养鹤的营养水平和环境有关。因此血液生化指标对于圈养鹤类营养状态和健康情况的判断具有重要参考价值,对圈养动物饲养管理具有重要的指导作用。  相似文献   

14.
鄱阳湖是世界重要的候鸟越冬地,承载了全球约98%的白鹤(Leucogeranus leucogeranus)。然而,近年来鄱阳湖沉水植被退化严重,白鹤的传统食物苦草(Vallisneria spp.)冬芽丰富度急剧减少。食物短缺导致白鹤的觅食生境由自然湿地的浅水生境转移至稻田、藕塘等人工生境,稻田在白鹤保护中发挥的作用日益突出。了解鄱阳湖周边稻田对白鹤的承载力可为白鹤的保护和管理提供科学依据。为此,调查了鄱阳湖周边稻田散落稻谷的生物量,测量了稻谷的营养成分,并利用遥感影像对鄱阳湖周边10 km范围内稻田的总面积进行估算,从而得出鄱阳湖周边稻田散落稻谷能提供的总能量。然后,计算稻田中以稻谷为主要食物的6种鸟类的日能量消耗,用以表示日能量摄入。最后,依据稻田能提供的总能量、鸟类的日能量摄入、鸟类的越冬时长、以及各种鸟类的数量占比,计算得出鄱阳湖周边稻田能承载的白鹤数量。结果表明,鄱阳湖周边稻田散落稻谷的生物量为6.494 g/m2,环鄱阳湖周边10 km范围内稻田的总面积为1984.46 km2,这些稻田能承载的鸟类总数量为140860只,其中能承载的白鹤数量为10775只,超过了全球白鹤的总数量(3500-4000只)。因此,鄱阳湖周边稻田能为白鹤等鸟类提供丰富的食物资源。  相似文献   

15.
黑颈鹤越冬生态初步研究   总被引:11,自引:1,他引:10  
黑颈鹤为我国特产珍稀动物,作者于1975和1978至1984年间,对它的越冬生态进行了观察。观察得知,黑颈鹤每年10月中、下旬迁来草海,翌年8月中下旬离去,越冬期为5个月左右。越冬期,有3种不同的集群形式,即家族群、同种集群和混种集群。主要食物为植物。黑颈鹤在草海越冬的数量,已由1975年的35只,增加到1984年的305只。黑颈鹤除在草海越冬外,还发现于威宁东南的普安县,是迄今所知在我国分布最南和最东的纪录。  相似文献   

16.
Endangered whooping cranes (Grus americana) have been produced in captivity for reintroduction programs since the 1980s, using techniques such as artificial insemination, multiple clutching, and captive-rearing to speed recovery efforts. Chicks are often hand-reared (HR) by caretakers in crane costumes, socialized into groups and released together, unlike parent-reared (PR) cranes that are raised individually by a male/female crane pair and released singly. HR cranes historically exhibit greater morbidity rates during development than PR cranes, involving musculoskeletal and respiratory system disease, among others. We hypothesized that HR crane chicks exhibit a higher baseline fecal glucocorticoid metabolite (FGM) concentrations during the development compared with PR chicks. Fecal samples were collected between 15 and 70 days of age from HR (n = 15) and PR (n = 8) chicks to test for differences in FGM concentrations using a radioimmunoassay technique following ethanol extraction for steroids. Linear mixed model analysis suggests increasing age of the chick was associated with an increase in FGM (p < .001). Analysis also supported the interaction between rearing strategy and sex of the crane chick (p < .01). Female PR chicks had greater FGM concentrations than all other groups (PR male, p < .01; HR female, p < .001; and HR male, p < .001). This result suggests that there may be an effect of rearing strategy on stress physiology of whooping crane chicks, especially among females. Further research is needed to investigate whether the FGM concentrations are reflective of true differences in stress physiology of young cranes and whether this may impact health and conservation success.  相似文献   

17.
对鸟类巢期的研究不仅可以丰富鸟类繁殖生物学资料,也可为理解和研究鸟类的生态适应与进化提供重要线索和依据。2013—2014年3月份至7月份,在若尔盖湿地保护区及周边对55对繁殖黑颈鹤的营巢时长进行了研究,调查结果显示:黑颈鹤的营巢时长在0.5—40 d之间,平均巢期为(6.7±9.3)d;在其营造的4种巢型中,巢期长短依次为:泥堆巢草堆巢草墩巢岛地巢,且差异性极显著(P0.001),巢期与巢型显著相关(r=0.728);在其营巢的3种巢址生境中,巢期长短依次为:湖泊生境沼泽生境河流生境,且差异性极显著(P0.001),巢期与巢址生境显著相关(r=0.315);从不同营巢月份看,巢期长短依次为:4月份巢5月份巢6月份巢,且差异性极显著(P0.01),巢期与筑巢月份显著相关(r=0.664);巢期与巢体积大小具有显著相关性(r=0.856),即营巢时间越长巢体积越大。黑颈鹤的营巢时间长短主要受营巢生境、月份和做巢类型的影响。  相似文献   

18.
The feces of 212 sandhill cranes (Grus canadensis) collected in central New Mexico from October 1982 to January 1983 and from October 1983 to January 1984 were examined to determine the prevalence of coccidial oocysts. One hundred forty-five granulomatous nodules from the viscera of 64 cranes and samples of lung, small intestine, and large intestine from 58 birds were examined by light and transmission electron microscopy for the presence of intestinal or extraintestinal coccidiosis. Of the 212 fecal samples, 160 (75%) were positive for oocysts of Eimeria, including E. gruis in 139 (66%) and E. reichenowi in 118 (56%) of the samples. Eimeria bosquei sp. n. was found in two (approximately 1%) of the fecal samples. Subspheroid to ovoid oocysts of this new species are 19-27 X 14-19 (23.6 X 17.1) micrograms with ovoid sporocysts 10-14 X 7-11 (12.3 X 9.3) micrograms. A rough, heavily pitted outer oocyst wall, sporocyst residuum, Stieda and substieda bodies, and multiple polar bodies are present. The polar bodies, of varying sizes, always aggregate at the apex of the sporulated oocyst. An Adelina sp. was found in one (0.5%) crane. Coccidian developmental stages were found in the epithelium and lamina propria of the small and large intestine. Disseminated granulomatous nodules were found in the oral mucosa, esophagus, heart, descending aorta, liver, small intestine, mesenteries, and parietal peritoneum. Unique cell types resembling coccidian asexual and sexual stages were observed by light and electron microscopy in some of the nodules.  相似文献   

19.
Davidson DW  Cook SC  Snelling RR 《Oecologia》2004,139(2):255-266
Disparities in liquid-feeding performances of major ant taxa have likely been important to resource partitioning among ants, to the nature and composition of ant partnerships with plants and sap-feeding trophobionts, and to ecological and evolutionary diversification of ant taxa. We measured performance volumetrically for individual workers of 77 ant species from lowland rain forests of Amazonia and Borneo and three key North American taxa. In trials with 9% sucrose solution, performances were strongly related to body size (and alitrunk length) and to proventricular structure at generic to subfamilial levels. Highly modified proventriculi were associated with disproportionately large load sizes in Formicinae and certain small-bodied Dolichoderinae. These same taxa also ingested liquids more rapidly during foraging than did similar-sized species with plesiomorphic proventriculi. Secondarily reduced foraging performances of several formicines likely reflect ecological or evolutionary trade-offs related to dietary specialization or anti-predator defenses. Across formicines and dolichoderines, performances differed by functional group. Relatively small loads and slow uptake characterized species tending trophobionts (mainly Hemiptera) day and night in large worker aggregations. Large loads and rapid uptake typified solitary, diurnal leaf-foragers. Intermediate feeding performances characterized a few species that both tended trophobionts in small aggregates and frequently foraged alone.Electronic Supplementary Material Supplementary material is available in the online version of this article at An erratum to this article can be found at  相似文献   

20.
We used radioimmunoassay to determine fecal corticoid concentrations and assess potential stress in 10 endangered whooping cranes (Grus americana) undergoing reintroduction to the wild. Fecal samples were collected shortly after hatching at a captive facility in Maryland, during field training in Wisconsin, and throughout a human‐led migration to Florida. After a 14‐day decline following hatching, fecal corticoid concentrations stabilized at baseline levels for the duration of the captive period, despite exposure to potentially stressful stimuli. Shipment of the cranes to the field training site was correlated with an eight‐ to 34‐fold increase in fecal corticoid concentrations, which returned to baseline levels within 1 week. Increases were positively correlated with age but not body weight at the time of shipping. Fecal corticoid concentrations during the training period increased slightly and exhibited greater variation than levels observed at the captive facility, but were well within expected norms based on previous studies. Fecal corticoid concentrations increased twofold following premigration physical examinations and placement of radiotransmitters, and persisted for up to 4 days before they returned to baseline levels. Though fecal corticoid concentrations and variation during the migration period were similar to training levels, there was an overall decline in fecal corticoid concentrations during the artificial migration. Acute stressors, such as capture, restraint, and severe storms, were associated with stress responses by the cranes that varied in accordance with lasting physical or psychological stimuli. The overall reintroduction process of costume‐rearing, ultralight aircraft habituation, training, and artificial migration was not associated with elevations in fecal corticoid concentrations suggestive of chronic stress. Zoo Biol 24:15–28, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   

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