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Discovery of four natural clones in a crayfish species Procambarus clarkii
G. H. Yue, G. L. Wang, B. Q. Zhu, C. M. Wang, Z .Y. Zhu, L. C. Lo
International Journal of Biological Sciences , 2008,
Abstract: Self-cloning is quite rare in shrimp, lobsters, crayfish and crabs. Here we report the discovery of four natural clones of red swamp crayfish (Procambarus clarkii), each containing 2-6 genetically identical individuals, during the genotyping of 120 individuals with five microsatellites. The four clones were heterozygote at most of the five microsatellite loci. Phylogenetic analysis using microsatellite genotypes suggests recent origin of the four clones. Sequencing a part of the mitochondrial gene Cox I confirmed that the four clones were from the species Procambarus clarkii.
High prevalence of multiple paternity in the invasive crayfish species, Procambarus clarkii
Gen Hua Yue, Jia Le Li, Chun Ming Wang, Jun Hong Xia, Gen Lin Wang, Jian Bing Feng
International Journal of Biological Sciences , 2010,
Abstract: Reproductive strategy is a central feature of the ecology of invasive species as it determines the potential for population increase and range expansion. The red swamp crayfish, Procambarus clarkii, has invaded many countries and caused serious problems in freshwater ecosystems. However, little is known about the effects of environmental conditions on crayfish paternity and offspring traits in the wild. We studied these reproductive characteristics of P. clarkii in wild populations from two different habitats (ponds and ditches) in three locations with different environmental conditions in China. Genotyping of 1,436 offspring and 30 mothers of 30 broods was conducted by using four microsatellites. An analysis of genotyping results revealed that gravid females were the exclusive mother of the progeny they tended. Twenty-nine of 30 mothers had mated with multiple (2-4) males, each of which contributed differently to the number of offspring in a brood. The average number of fathers per brood and the number of offspring per brood were similar (P > 0.05) among six sampling sites, indicating that in P. clarkii multiple paternity and offspring number per brood are independent of environmental conditions studied. Indirect benefits from increasing the genetic diversity of broods, male and sperm competition, and cryptic female choice are a possible explanation for the high level multiple paternity and different contribution of fathers to offspring in this species.
Predation impact of Procambarus clarkii on Rana limnocharis tadpoles in Guilin area

Zhengjun Wu,Fengjin Cai,Yunfeng Jia,Jianxin Lu,Yongfu Jiang,Chengming Huang,

生物多样性 , 2008,
Abstract: 克氏原螯虾(Procambarus clarkii)已入侵我国江苏、湖北、江西、安徽等多个省(市)。为研究克氏原螯虾对其生境中主要两栖动物泽蛙(Rana limnocharis)的影响,我们于2006年5-6月对广西桂林地区自然生境中克氏原螯虾和泽蛙蝌蚪的数量和密度进行了调查,7月在室内进行了克氏原螯虾对泽蛙蝌蚪和饰纹姬蛙(Microhyla ornata)蝌蚪的捕食实验。野外调查结果表明克氏原螯虾的密度与泽蛙蝌蚪的密度呈显著负相关。室内实验结果表明克氏原螯虾对泽蛙蝌蚪的捕食强度与克氏原螯虾体长呈显著正相关,且对泽蛙蝌蚪的捕食强度高于饰纹姬蛙蝌蚪。表明克氏原螯虾对两栖类幼体有比较严重的危害,应加强监测,采取相应措施预防和控制其危害。
Can native species crucian carp Carassius auratus recognizes the introduced red swamp crayfish Procambarus clarkii?  [cached]
Fengjin CAI, Zhengjun WU, Nan HE, Zhenxing WANG, Chengming HUANG
Current Zoology , 2011,
Abstract: Procambarus clarkii is native to the south-central United States (Louisiana) and northeastern Mexico, and is a highly efficient predator that poses a damager to native species after its introduction or invasion. In its natural habitat, P. clarkii consumes Carassius auratus, however, whether C. auratus recognizes P. clarkii as a predator is not yet clear. In laboratory experiments, we investigated whether experienced and inexperienced C. auratus recognize P. clarkii as a predatory threat and the specific sensory modality used by C. auratus to respond to chemical and visual stimuli from P. clarkii. In the chemical stimuli experiment, two kinds of chemical stimuli were used, water from a tub containing P. clarkii previously fed with C. auratus (C. auratus diet cues) and water from a tub containing unfed P. clarkii (P. clarkii cues). In the visual experiment, experienced C. auratus decreased activity, but inexperienced C.auratus avoided the predator compartment. When C. auratus diet cues were presented, both experienced and inexperienced C. auratus increased the use of shelter, decreased activity in the initial response phase. Compared with the blank treatment, experienced C. auratus responded to P. clarkii cues by decreasing activity; however, inexperienced C. auratus showed no reduction in activity. C. auratus appears to recognize P. clarkii as a predator both through visual and chemical cues. Further analysis revealed that C. auratus may recognize P. clarkii visually through the disturbances caused by P. clarkii movement and chemically by detecting conspecific alarm cues in the diet of P. clarkii. The results also indicate that experienced C. auratus can recognize P. clarkii by innate chemical cues from P. clarkii, whereas inexperienced C. auratus cannot [Current Zoology 57 (3): 330–339, 2011].
Acute Toxicity of Ten Pesticides to Larval Red Swamp Crayfish Procambarus Clarkii
10种农药对克氏原螯虾幼虾的急性毒性(Acute Toxicity of Ten Pesticides to Larval Red Swamp Crayfish Procambarus Clarkii)

XU Yi,LIU Qi-gen,HU Zhong-jun,SHEN Hong,CAO Jun-yun,TONG Liu-qing,

生态毒理学报 , 2010,
Abstract: 研究了在实验室常温条件下敌杀死、索虫亡、百草一号、敌敌畏、卷清、逐灭(池塘水)、逐灭(自来水)、锐劲特、抑虱净、草甘膦、星科等10种农药对克氏原螯虾(Procambarus clarkii)幼虾的急性毒性效应. 试验结果表明,克氏原螯虾幼虾对不同农药的耐受力相差较大. 敌杀死、索虫亡、百草一号、敌敌畏、卷清、逐灭(池塘水)、逐灭(自来水)、锐劲特、抑虱净、草甘膦、星科对克氏原螯虾幼虾的24h半致死浓度(24h LC50)分别为4.62×10-3、2.28×10-2、16.7、2.57×10-1、4.73×10-3、8.91×10-2、2.97×10-2、8.90×10-2、8.08、5.52×103、3.64×10-1mg·L-1;48h半致死浓度(48h LC50)分别为3.07×10-3、1.46×10-2、15.8、1.98×10-1、4.33×10-3、3.48×10-2、1.48×10-2、6.01×10-2、6.47、4.06×103、1.99×10-1mg·L-1;其安全浓度(SC)分别为4.07×0-4、1.80×10-3、4.16、3.72×10-2、1.09×10-3、1.59×10-3、1.10×10-3、8.22×10-3、1.24、6.59×102、1.78×10-2mg·L-1. 相比之下,草甘膦对克氏原螯虾幼虾的毒性最低,百草一号的毒性也相对较低,可以作为稻虾混养系统病虫害防治的首选,而敌杀死、卷清等对克氏原螯虾幼虾的毒性极高,应尽量避免使用.
The Study and Predict on the Surface Structure and the Characteristics of Pincers of Crawfish (Procambarus Clarkii)  [cached]
Guangsheng ZHAO,Yinwu LI,Cheng YANG,Xiuwen SUN
Advances in Natural Science , 2011, DOI: 10.3968/j.ans.1715787020110401.004
Abstract: Based on the introduction of biological non-smooth surface and the characteristics of drag reduction and wear resistance, a series of macroscopic and microcosmic observation and analysis on the surface structure of pincers of crawfish (Procambarus clarkii) were finished with the OLYMPUS stereo microscope and LSCM (Laser Scanning Confocal Microscope). The results indicate that the surface of pincers of crawfish is mainly constituted by small pits, small semicircle bumps and small stripe-type groove, and there are clusters of bristles which have a lot of spinules in their surface within the pit and around the small bump. It shows the surface of pincers of crawfish is non-smooth and has typical non-smooth surface characteristics. In addition,by analyzing the variation rules of small haplonts(pits and bumps) in the non-smooth surface of pincers of crawfish, authors get the conclusion that the keystone and direction of the non-smooth surface study should be focused on the quantitative analysis to the changes( size, form, and the distribution) of the small haplonts influence on the characteristics of the drag reduction and wear resistance, and its engineering application. Key words: Non-Smooth Surface; Pincers of Crawfish; Drag Reduction; Wear Resistance
Population Genetic Structure and Post-Establishment Dispersal Patterns of the Red Swamp Crayfish Procambarus Clarkii in China  [PDF]
Yanhe Li, Xianwu Guo, Xiaojuan Cao, Wei Deng, Wei Luo, Weimin Wang
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0040652
Abstract: The red swamp crayfish (Procambarus clarkii) was introduced to China in the early 20th century. It has been spread to almost all forms of fresh water bodies including lakes, rivers and even paddyfields in most provinces of China. To clarify issues such as the initial entry point(s), dispersal pattern, genetic diversity and genetic structure of Procambarus clarkii in China, the genetic structure and diversity of P. clarkii populations at 37 sampling sites (35 from China, one from the USA and one from Japan) were analyzed using both mitochondrial gene sequences (COI and 16S rRNA) and 12 nuclear microsatellites. Multiple tests including phylogenetic analyses, Bayesian assignment and analysis of isolation by distance showed that (i) the population from Japan and those collected from China, particularly from NanJing (BGt and XG) and its some neighboring sites (CJr, NT and NB), have similar genetic composition, (ii) relatively high genetic diversity was detected in Chinese populations, (iii) the P. clarkii populations in China did not experience significant population expansions. Taken together, Nanjing, Jiangsu province is the presumed initial entry point, and human-mediated dispersal and adaptive variation are likely responsible for the observed genetic pattern of P. clarkii in China.
Studies on the Appropriate Protein Requirement and Energy to Protein Rati0 in Feed for Procambarus clarkii

HE Ji-xiang,WANG Zhi-geng,MEI Lin,YAO Cheng-hu,DONG Juan-juan,HUANG Xia,

水生态学杂志 , 2009,
Abstract: 采用3×3因子试验法,设计了3种不同蛋白质水平(26%、29%、32%)及能最蛋白比水平(36、40、44 kl/g)的9种试验饲料,对体重(2.39±0.37)g的克氏螯虾(Procambarus clarkii)的适宜蛋白质含量及其蛋白能最比进行了研究,生长试验期42 d.结果表明,克氏螫虾幼虾配合饲料中适宜蛋白质含量为29.49%~32.24%,饲料的适宜能量蛋白比范嗣为34.67~37.46 kJ/g;当试验饲料蛋白质含量为31.86%,能量蛋白比为35.85 kJ/g时,试验虾获得最大增重率、最低的饲料系数、最高的蛋白质效率及最大的特定生长率.
A dynamical population modeling of invasive species with reference to the crayfish Procambarus Clarkii  [PDF]
Gianluca Martelloni,Franco Bagnoli,Stefano Marsili Libelli
Quantitative Biology , 2012,
Abstract: In this paper we present a discrete dynamical population modeling of invasive species, with reference to the swamp crayfish Procambarus clarkii. Since this species can cause environmental damage of various kinds, it is necessary to evaluate its expected in not yet infested areas. A structured discrete model is built, taking into account all biological information we were able to find, including the environmental variability implemented by means of stochastic parameters (coefficients of fertility, death, etc.). This model is based on a structure with 7 age classes, i.e. a Leslie mathematical population modeling type and it is calibrated with laboratory data provided by the Department of Evolutionary Biology (DEB) of Florence (Italy). The model presents many interesting aspects: the population has a high initial growth, then it stabilizes similarly to the logistic growth, but then it exhibits oscillations (a kind of limit-cycle attractor in the phase plane). The sensitivity analysis shows a good resilience of the model and, for low values of reproductive female fraction, the fluctuations may eventually lead to the extinction of the species: this fact might be exploited as a controlling factor. Moreover, the probability of extinction is valuated with an inverse Gaussian that indicates a high resilience of the species, confirmed by experimental data and field observation: this species has diffused in Italy since 1989 and it has shown a natural tendency to grow. Finally, the spatial mobility is introduced in the model, simulating the movement of the crayfishes in a virtual lake of elliptical form by means of simple cinematic rules encouraging the movement towards the banks of the catchment (as it happens in reality) while a random walk is imposed when the banks are reached.
Accumulation of Copper, Lead, Chrome, Cadmium in Some Tissues of Procambarus clarkii in Rharb Region in Morocco  [PDF]
Ikram El Qoraychy, Mohamed Fekhaoui, Abdellah El Abidi, Rachid Benakame, Abdelkbir Bellaouchou, Ahmed Yahyaoui
Journal of Geoscience and Environment Protection (GEP) , 2015, DOI: 10.4236/gep.2015.38008
Abstract: Different concentrations of four metals namely copper, lead, chrome and cadmium were evaluated in crayfish Procambarus clarkii tissues (carapace, flesh) for a six-month period, from March to August 2013 in the Rharb of Morocco (Lagoon Merja Zerga and Nador canal). The determination of heavy metals was carried using atomic absorption spectroscopy Varian VV20. The results obtained revealed a metal’s contamination of Procambarus clarkii in both sites. Concentrations of heavy metals examined Procambarus clarkii carapace ranged as follows: Merja Zerga (Pb 2.07 - 6.7 μg/g; Cu 2.9 - 9.97 μg/g; Cr 0.89 - 14.22 μg/g dry weight) and Nador canal: (Pb 0.08 - 7.8 μg/g; Cu 3.40 - 9.3 μg/g ; Cr 0.87 - 3.5 μg/g dry weight). Concentrations of heavy metals found in flesh were as follows: Merja Zerga (Pb 0.02 - 5.25 μg/g; Cu 9.58 - 23.59 μg/g; Cr 0 - 2.71 μg/g dry weight) and Nador canal (Pb 0.06 - 6.81 μg/g; Cu 9.5 - 37.20 μg/g; Cr 0 - 3.23 μg/g dry weight). The distribution of those metals in Procambarus clarkii shows high levels of contamination for lead, copper and chrome with an absence of cadmium in both sites (Merja Zerga and Nador canal). The concentrations differed in carapace and flesh.
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