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1.
The complete amino acid sequence of the major component of hemoglobin from amur-leopard (Panthera pardus orientalis) is presented. The major component accounts for more than 90% of the total hemoglobin. Separation of the globin subunits was achieved by ion-exchange chromatography on CM-cellulose in urea. The sequence was studied by automatic Edman degradation of tryptic and hydrolytic peptides. Alignment was carried out with human hemoglobin sequence. The NH2 terminus is blocked with Ac-serine. The data are compared with other mammalian hemoglobins and results are discussed with respect to sequence and physiology.85th communication on hemoglobin.  相似文献   
2.
Replicated multiple scale species distribution models (SDMs) have become increasingly important to identify the correct variables determining species distribution and their influences on ecological responses. This study explores multi‐scale habitat relationships of the snow leopard (Panthera uncia) in two study areas on the Qinghai–Tibetan Plateau of western China. Our primary objectives were to evaluate the degree to which snow leopard habitat relationships, expressed by predictors, scales of response, and magnitude of effects, were consistent across study areas or locally landcape‐specific. We coupled univariate scale optimization and the maximum entropy algorithm to produce multivariate SDMs, inferring the relative suitability for the species by ensembling top performing models. We optimized the SDMs based on average omission rate across the top models and ensembles’ overlap with a simulated reference model. Comparison of SDMs in the two study areas highlighted landscape‐specific responses to limiting factors. These were dependent on the effects of the hydrological network, anthropogenic features, topographic complexity, and the heterogeneity of the landcover patch mosaic. Overall, even accounting for specific local differences, we found general landscape attributes associated with snow leopard ecological requirements, consisting of a positive association with uplands and ridges, aggregated low‐contrast landscapes, and large extents of grassy and herbaceous vegetation. As a means to evaluate the performance of two bias correction methods, we explored their effects on three datasets showing a range of bias intensities. The performance of corrections depends on the bias intensity; however, density kernels offered a reliable correction strategy under all circumstances. This study reveals the multi‐scale response of snow leopards to environmental attributes and confirms the role of meta‐replicated study designs for the identification of spatially varying limiting factors. Furthermore, this study makes important contributions to the ongoing discussion about the best approaches for sampling bias correction.  相似文献   
3.
为了将有限资源合理投放到关键区域, 实现物种保护成效的最大化, 找出质量最好的栖息地及它们之间的迁徙通道是制定保护规划的第一步。本研究以三江源的雪豹(Panthera uncia)栖息地为对象, 基于野外调查数据和高分辨率卫星遥感数据, 利用物种分布模型、保护规划模型和连通度分析工具, 找出了三江源地区雪豹的核心栖息地分布和潜在迁徙通道位置, 分析了目前保护中的潜在威胁, 并提出了针对三江源西、中、东三块区域的不同保护对策。结果表明: (1)三江源西部核心栖息地比较小而破碎, 但迁徙通道较多且没有明显窄点, 未来应关注青藏线的潜在阻碍作用, 同时应防范道路沿线的野生动物盗猎; (2)中部区域横跨玉树-杂多-囊谦的雪豹栖息地是三江源最大的核心雪豹栖息地, 在连通其他种群中也处于中心地位, 应通过种群监测确定其健康稳定, 对开发、偷猎等威胁防微杜渐, 保持其源种群的作用; (3)东部区域人口密度高, 受人类活动的影响最大, 需保证阿尼玛卿、年保玉则两块核心栖息地的质量, 并重点监测甘德县境内的省道处雪豹的迁徙通道是否畅通。三江源地区雪豹栖息地总体质量较好, 建议将维持核心源种群的稳定性, 保持种群间迁徙通道的畅通作为三江源的雪豹景观保护工作的整体目标。未来应充分利用天地一体化监测手段, 开展重要保护物种栖息地状况的评估和预警, 尤其是非保护地区域物种核心栖息地的开发建设活动。  相似文献   
4.
雪豹是全球生物多样性保护的旗舰物种,精准评估雪豹栖息地质量可为其种群保护提供科学参考。本文选取地形、气候、植被类型和人为干扰等环境因子,采用景观连接度和MaxEnt模型两种方法,对祁连山国家公园青海片区雪豹栖息地质量进行评价。结果表明:高适宜栖息地主要分布在研究区的西部和中部,适宜面积占青海片区总面积的71.8%~77.5%,两种方法预测的适宜栖息地重叠区为8 979.1 km2,占青海片区总面积的56.7%;39.8%~43.3%的适宜栖息地分布在一般控制区,56.7%~60.2%的适宜栖息地分布在核心保护区;疏勒河源区适宜栖息地面积最多,石羊河源区适宜栖息地面积最少,黑河源区适宜栖息地面积占比最高,约为77.1%~91.8%。适宜栖息地面积整体呈现自东向西递增的趋势。一般控制区分布有较大面积的雪豹栖息地,人类活动将是一般控制区雪豹栖息地的潜在威胁。本研究对优化雪豹就地保护措施提供科学借鉴与参考。  相似文献   
5.
Socio‐ecological theory predicts that group fusion in female‐philopatric primate species will be rare because females experience increased costs by associating with non‐relatives. Indeed, fusion has been reported only 14 times in only 4 female‐philopatric cercopithecines despite many years of observation. Here, we describe changes in ranging and agonistic behavior of vervet monkeys (Cercopithecus aethiops) after the fusion of two groups, the sole group fusion during 11 years of observation, induced by a brief but intense period of apparent leopard predation. Before fusion, both groups made few incursions into the other group's territory and spent most of the time in their own territories. After the fusion, the amalgamated group shifted its activities and used both territories in similar proportion. Rates of female agonism increased after fusion, particularly in the 2 weeks following fusion, and the small group females assumed the lowest ranks in the female dominance hierarchy. Rates of agonism returned to prefusion rates a month later. Although rates of high‐intensity interactions (i.e., chases) did not increase after fusion, small group females were more likely to be the recipients of, and lose, agonistic interactions than large group females; a small group female and her infant were attacked and wounded by a coalition of large group females shortly after the fusion. The observations presented here reveal that the circumstances surrounding group fusions are more variable than previously realized, but are still in accordance with expectations from socio‐ecological theory that predation can favor the formation of larger groups. In this case, under threat of severe predation, individuals may have surrendered group autonomy for the greater security of larger numbers. Am. J. Primatol. 72:634–644, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
6.
I. Adachi  E. Nagao  M. Asano  O. Doi 《Theriogenology》2010,74(8):1499-1503
Although the Tsushima leopard cat (Prionailurus bengalensis euptilurus) is one of the most endangered mammals in Japan, its reproductive physiology and endocrinology have been not elucidated. The objective was to establish the non-invasive monitoring of reproductive endocrinology in a female Tsushima leopard cat and to identify the types of fecal reproductive steroid metabolites in this species. Fecal concentrations of estrogen and progestin were determined by enzyme immunoassays, from 60 d before to 60 d after the last copulation, during three pregnancies. Fecal estrogen metabolite concentrations were increased before/around the mating period and after mid-pregnancy. Fecal progestin metabolite concentrations increased after the last copulation and remained high during pregnancy. The gestation period was 65.0 ± 0.6 d (mean ± SD). Fecal extracts were separated by high-performance liquid chromatography for identification of fecal metabolites. Fecal estrogens were identified as estradiol-17β and estrone. Fecal progestins during pregnancy contained 5α-reduced pregnanes: 5α-pregnan-3α-ol-20-one, 5α-pregnan-3β-ol-20-one and 5α-pregnan-3,20-dione, and nonmetabolized progesterone was barely detected in feces. In conclusion, measurement of fecal estrogen and progestin metabolites was effective for noninvasive reproductive monitoring in the Tsushima leopard cat. An immunoassay for fecal estradiol-17β concentrations seemed useful to monitor follicular activity, whereas an immunoassay with high cross reactivity for 5α-reduced pregnanes was useful to monitor ovarian luteal activity and pregnancy.  相似文献   
7.
We immobilized 200–550-kg leopard seals ( Hydrurga leptonyx ) on sea ice in Prydz Bay, Antarctica (68°25'S, 77°10'E) between November 1997 and February 2000. Midazolam (0.18–0.27 mg/kg)/ pethidine (1.0–1.5 mg/kg) was administered by dart to 16 leopard seals. Unpredictable immobilization, poor airway maintenance, and our inability to fully assess the suitability of flumazenil (0.003–0.01 mg/kg), naloxone (0.01–0.013 mg/kg), and naltrexone (0.05–0.12 mg/kg) as reversal agents limited suitability of midazolam/pethidine. Tiletamine/zolazepam 1:1 (0.5–1.5 mg/kg) was, therefore, administered to 19 leopard seals. It produced faster induction (19 ± 3 min), more effective and reliable response to dose (rank correlation: r s= 0.88, n = 18), and better pulmonary ventilation and faster return of cognitive function upon recovery, in comparison to midazolam/pethidine. Best results were achieved with tiletamine/zolazepam (1.2–1.4 mg/kg) which safely immobilized seven of nine seals for 20–30 min. Entry to the water upon darting was minimized, but not eliminated, by the use of lightweight air-pressurized darts and a thorough knowledge of leopard seal behavior.  相似文献   
8.
9.
Abstract: Problem Animal Control Registers, where farmers report livestock losses due to predators as a prerequisite for financial compensation, allow quantifying the human-predator conflict. We analyzed such registers from the Kweneng District of Botswana to assess the impact of native predators on livestock over 3 years. Leopards (Panthera pardus), lions (Panthera leo), wild dogs (Lycaon pictus), brown hyenas (Hyaena brunnea), and cheetahs (Acinonyx jubatus) altogether claimed 2,272 head of livestock. During 2002, the year with the highest impact, the number of animals reported depredated (954) represented 0.34% of the livestock in the district. Leopards and lions caused 64% of the losses. Leopard livestock predation mainly affected calves and was consistent over the district and over time. In contrast, lion predation concentrated on adult cattle, was characterized by local hot spots close to reserve borders, decreased with increasing distance to a reserve, and increased during 2002, an unusually dry year. Interviews with 60 farmers and herders within 30 km of Khutse and Central Kalahari Game Reserves revealed an annual loss of 2.2% of their livestock to predators. Here, small farms (max. 100 domestic animals) suffered relatively higher losses than large, commercial farms, not only due to predation (small farms: 11.7%; large farms: 1.0%) but also from other causes (small: 12.6%; large: 2.8%), even though herders on large farms guarded 5 times more livestock per person than those on small farms. To reduce livestock predation in most of the district where lions are absent, we recommend maternity corrals for pregnant females and calves to better protect vulnerable calves during day and night. In areas close to a reserve where lions roam, herders' incentives to keep all livestock protected in a corral at night have to be enhanced because, according to the registers, only 3 predation cases were reported to have happened inside a corral.  相似文献   
10.
Transferrins, found in invertebrates and vertebrates, form a physiologically important family of proteins playing a major role in iron acquisition and transport, defense against microbial pathogens, growth and differentiation. These proteins are bilobal in structure and each lobe is composed of two domains divided by a cleft harboring an iron atom. Vertebrate transferrins comprise of serotransferrins, lactoferrins and ovotransferrins. In mammals serotransferrins transport iron in physiological fluids and deliver it to cells, while lactoferrins scavenge iron, limiting its availability to invading microbes. In oviparous vertebrates there is only one transferrin gene, expressed either in the liver to be delivered to physiological fluids as serotransferrin, or in the oviduct with a final localization in egg white as ovotransferrin. Being products of one gene sero- and ovotransferrin are identical at the amino-acid sequence level but with different, cell specific glycosylation patterns. Our knowledge of the mechanisms of transferrin iron binding and release is based on sequence and structural data obtained for human serotransferrin and hen and duck ovotransferrins. No sequence information about other ovotransferrins was available until our recent publication of turkey, ostrich, and red-eared turtle (TtrF) ovotransferrin mRNA sequences [Ciuraszkiewicz, J., Olczak, M., Watorek, W., 2006. Isolation, cloning and sequencing of transferrins from red-eared turtle, African ostrich and turkey. Comp. Biochem. Physiol. 143 B, 301-310]. In the present paper, ten new reptilian mRNA transferrin sequences obtained from the Nile crocodile (NtrF), bearded dragon (BtrF), Cuban brown anole (AtrF), veiled and Mediterranean chameleons (VtrF and KtrF), sand lizard (StrF), leopard gecko (LtrF), Burmese python (PtrF), African house snake (HtrF), and grass snake (GtrF) are presented and analyzed. Nile crocodile and red-eared turtle transferrins have a disulphide bridge pattern identical to known bird homologues. A partially different disulphide bridge pattern was found in the Squamata (snakes and lizards). The possibility of a unique interdomain disulphide bridge was predicted for LtrF. Differences were found in iron-binding centers from those of previously known transferrins. Substitutions were found in the iron-chelating residues of StrF and TtrF and in the synergistic anion-binding residues of NtrF. In snakes, the transferrin (PtrF, HtrF and GtrF) N-lobe "dilysine trigger" occurring in all other known transferrins was not found, which indicates a different mechanism of iron release.  相似文献   
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