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51.
The temporal and spatial patterns of rat abundance variations were studied, and which factors might affect these patterns in poultry farms. Forty-eight poultry farms were sampled from spring 1999 to winter 2001 in Buenos Aires, Argentina. Environmental variables of farms, meteorological variables and distances among farms were registered to evaluate a possible association with rat abundance estimated by trap success. Rattus norvegicus was the dominant rat species in the study area. Rat abundance did not vary temporally and there was reproduction at all times. Trap success was more similar among neighboured farms than among farms further apart. Contrary to the abundance of other small rodents, rat abundance was not significantly related to farm characteristics. The lack of coincidence between rats and other small rodents suggests the existence of a differential response of rats to environmental factors of the poultry farms.  相似文献   
52.
第二代抗凝血灭鼠剂因比第一代抗凝血灭鼠剂有更好的灭杀效果和安全性而被广泛使用,但长期使用同样也存在引发鼠类抗性的隐患。近年,学者已发现了第二代抗凝血灭鼠剂溴敌隆 (bromadiolone) 和鼠得克 (difenacoum) 的抗性鼠。溴鼠灵 (brodifacoum) 是一种目前在国内广泛使用且毒性极强的第二代抗凝血灭鼠剂,能引发鼠类凝血功能障碍和细胞毒性,但对于溴鼠灵是否已驱动鼠类发生抗性进化尚不清楚。澳门地区从1995年开始持续使用溴鼠灵,为研究鼠类对溴鼠灵的抗药性进化提供了良好模型。本研究于2019年10—12月在澳门地区共捕获61只褐家鼠,对其中44只开展了LFP实验 (0.005%溴鼠灵),实验鼠的平均摄毒量为 (15.28 ± 1.40) mg/kg,在7天内全部死亡。此外,对全部61只褐家鼠的维生素K环氧化物还原酶复合体亚单位1 (vitamin K-epoxide reductas complex 1, Vkorc1) 的基因序列测定表明,在Vkorc1基因外显子的已知抗药关联位点处未检测到非同义核苷酸突变,但检测到2个同义核苷酸突变 [第68位氨基酸:H (CAC)-H (CAT),突变发生率为100%;第82位氨基酸:I (ATA)-I (ATT),突变发生率为32.72%]。该研究表明,使用溴鼠灵25年后,澳门地区褐家鼠虽没有产生群体抗药性,但仍需持续监测抗药性的发生和发展。  相似文献   
53.
The amplitude of the daily rhythm of body temperature was investigated in 11 species of small mammals. Recording equipment, housing and environmental conditions were identical for all species. Intraperitoneal temperature was measured by telemetry at 6 min intervals for 10 or more days. The results indicate that the amplitude of the body temperature rhythm is a species-specific trait in small mammals. Interspecies differences in amplitude are not a function of surface area (as determined by body size) but seem to relate to diurnality (nocturnal species displaying smaller amplitude than diurnal ones) and habitat (species from temperate habitats displaying smaller amplitude than species from desert and tropical habitats).  相似文献   
54.
新疆褐家鼠肥满度的初步研究   总被引:3,自引:0,他引:3  
对在新疆北部干旱地区野外捕获765号褐家鼠标本进行了肥满度研究.结果表明,该鼠肥满度与年龄和栖息地无关,而有性别、季节和年度差异,肥满度变化与种群数量之间的相关程度均未达到显著水平,说明该鼠的肥满度不能作为预测其种群数量的主要指标.  相似文献   
55.
上海九段沙是长江口的新生岛洲,目前处于草本植物群落演替阶段。为了探讨登岛褐家鼠的挖掘活动对九段沙湿地植物群落与土壤水盐的影响,我们调查了褐家鼠洞穴区的植物盖度、密度、高度、重要值、物种丰富度、物种均匀度、物种多样性、表层土壤含水量和电导率等与对照区的差异;同时,通过调查褐家鼠洞穴与潮沟在空间位置上的关系探讨了褐家鼠的栖息地选择策略。结果表明:在单一芦苇群落中,洞穴区芦苇的高度和盖度显著低于对照;在芦苇和海三棱藨草混合群落中,洞穴区芦苇的密度、相对密度、重要值和群落总盖度显著低于对照,而洞穴区海三棱藨草的密度、盖度、相对密度、相对高度和重要值显著高于对照;在碱菀和互花米草优势群落中,洞穴区碱菀的相对密度、相对盖度、重要值和群落的物种多样性指数显著高于对照,而互花米草的密度和盖度、芦苇的盖度、高度和相对盖度以及群落总盖度显著低于对照。距洞穴区中心区域洞口不同距离梯度的表层土壤含水量和电导率差异均显著。褐家鼠偏向于将洞穴营造在邻近潮沟处,这有利于提高褐家鼠在九段沙湿地的适应能力。褐家鼠的挖掘活动有利于增加碱菀和互花米草优势群落的物种多样性,会降低植物群落总盖度和表层土壤的水盐含量,对九段沙湿地植物群落的组成与演替具有重要影响。  相似文献   
56.
Chaperonin 10 protein from Rattus norvegicus (Rat cpn10) has been reported to bind chaperonin 60 from Escherichia coli (GroEL) in an ATP-dependent manner. Chemically synthesized Rat cpn10 was immobilized in a defined orientation to agarose-bound monomeric avidin using a reversible biotinylated affinity label ( 1 ), attached to the Nα-terminal residue. The resulting affinity chromatographic matrix was then used to isolate binding proteins from a crude cell lysate. Following affinity separation the bound ligand and ligate was released by treatment with organic base. Rat cpn10 was prepared using a highly effective synthetic protocol involving HBTU/HOBt activation and capping with N-(2-chlorobenzyloxycarbonyloxy) succinimide to terminate unreacted amino groups. The biotinylated Fmoc-based molecule ( 1 ) was introduced specifically onto the Nα-terminal amino acid as the succinimidyl carbonate, before final cleavage and deprotection of side-chain protecting groups using a low-TFMSA/high-HF procedure. Crude biotinylated Rat cpn10 (Rat cpn10+ 1 ) was immobilized on monomeric avidin with a binding efficiency of approximately 75% and unlabelled truncated/capped impurities eluted off the column with buffer. The biotinylated Rat cpn10–avidin affinity matrix was then used to isolate GroEL from a crude cell lysate. The identity of the purified protein was confirmed by SDS–PAGE and binding to a specific anti-GroEL monoclonal antibody (MoAb). These results extend the applicability of the biotinylated label ( 1 ), providing a reversible non-covalent anchor for immobilization of peptide and protein ligands, thus simplifying isolation of ligates and enabling recovery of synthetic material under mild conditions. © 1997 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
57.
本文利用SOD和LDH在一块凝胶板上同时显色的优点,电泳分析黑线姬鼠(Apodemus agrarius)、褐家鼠(Rattus norvegicus),黄胸鼠(Rattus flavipectus)血浆SOD和LDH同工酶以及血浆蛋白成分。结果表明,LDH为有色区带,SOD为无色透明区带,而且SOD比LDH泳动快,两类区带互不重迭,以致3种鼠血浆中SOD和LDH的图谱清晰可辨。由于黑线姬鼠的SOD和LDH的泳动度不同于其余2种鼠,周此3种鼠的图谱各具特征。3种鼠血浆蛋白中的前清蛋白和铁传递蛋白区带数和泳动度亦具有明显差异,说明上述酶分子亚基和血浆蛋白分子的化学结构不同,成为种间差异在分子水平上典型的表现。  相似文献   
58.
In this work, the temperature dependence of the sarco-endoplasmic reticulum Ca(2+) -ATPase (SERCA2) activity from rainbow trout Oncorhynchus mykiss cardiac ventricles was measured and compared with the mammalian SERCA2 isoform. The rate of ATP-dependent Ca(2+) transport catalysed by O. mykiss vesicles was totally abolished by thapsigargin and the Ca(2+) ionophore A(23187) . At warm temperatures (25 and 30° C), the SERCA2 from O. mykiss ventricles displayed the same rate of Ca(2+) uptake. At 35° C, the activity of the O. mykiss enzyme decreased after 20 min of reaction time. The rate of Ca(2+) uptake catalysed by the mammalian SERCA2 was temperature dependent exhibiting its maximal activity at 35° C. In contrast to the rate of Ca(2+) uptake, the rate of ATP hydrolysis catalysed by O. mykiss SERCA2 was not significantly different at 25 and 35° C, but the rate of ATP hydrolysis catalysed by the rat Rattus norvegicus SERCA2 isoform at 35° C was two-fold higher than at 25° C. At low temperatures (5 to 20° C), the rate of Ca(2+) uptake from O. mykiss SR was less temperature dependent than the R. norvegicus isoform, being able to sustain a high activity even at 5° C. The mean ±s.e. Q(10) values calculated from 25 to 35° C for ATP hydrolysis were 1·112 ± 0·026 (n = 3) and 2·759 ± 0·240 (n = 5) for O. mykiss and R. norvegicus, respectively. Taken together, the results show that the O. mykiss SERCA2 was not temperature dependent over the 10 to 25° C temperature interval commonly experienced by the animal in vivo. The Q(10) value of SERCA2 was significantly lower in O. mykiss than R. norvegicus which may be key for cardiac function over the wide environmental temperatures experienced in this eurythermal fish.  相似文献   
59.
黄贵萍  廖若男 《兽类学报》1997,17(3):216-220
本文对野生大家鼠(Ratusnorvegicus)和Wistar品系实验大白鼠的血红蛋白(Hb)及组织的乳酸脱氢酶(LDH)同工酶进行了电泳分析,结果表明,两种鼠均表现了Hb的多态性,其中HbI型都含有8个成分,各成分的泳动率相同。两种鼠的心脏LDH同工酶都含有LDH1,LDH2,LDH3和LDH5,而且各谱带泳动率相近似,其余组织LDH谱带泳动率有明显的差异,表现了组织和种(或品系)的特异性。从电泳图谱上发现Wistar大鼠LDH5(A或M亚基纯合体)出现亚带,而LDH1(B或H亚基纯合体)则未发现,可确定变异是由于A或M亚基位点发生突变,出现等位基因而导致。对褐家鼠的LDH4出现亚带也进行了讨论  相似文献   
60.
A pleasing consequence of Norway rat eradication: two shrew species recover   总被引:1,自引:0,他引:1  
Four to 10 years after the successful eradication of the Norway rat (Rattus norvegicus) from three islands of the Sept–Îles Archipelago and one in the Molène Archipelago (Brittany, France), the abundance index of the lesser white‐toothed shrew (Crocidura suaveolens) increased by factors of 7–25, depending on the island and the year. Moreover, in the same region, the abundance index of the greater white‐toothed shrew (Crocidura russula) on Tomé Island increased by factors of 9 and 17, one and two years after the Norway rat eradication, respectively. The maximum variation of the abundance index for the lesser white‐toothed shrew during seven years on the rat‐free island of Béniguet in the same region was a factor of only 2.5. Moreover, the distribution of the lesser white‐toothed shrew on Bono island, restricted before the eradication to two steep areas with few rats, increased and encompassed virtually the entire island four years after rats disappeared. These results suggest strong detrimental interactions between the introduced Norway rat and the two Crocidura shrew species on temperate oceanic islands. However, our data do not indicate the ecological mechanisms at work in these interactions. The main reason this shrew recovery was detected after rat eradication was the inclusion in the eradication protocol of the evaluation of impacts on the local biota of eliminating alien species. The rigor of the sampling procedure was also crucial to this discovery. This example demonstrates that an eradication operation can be extremely useful for both scientists and managers if it is planned as a research project.  相似文献   
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