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1.
本文使用几何形态测量法探讨42例成年太行山猕猴Macaca mulatta tcheliensis髋臼的性别二态性。结果显示,太行山猕猴雌雄个体的髋臼形态具有明显的性别二态性,利用髋臼可以正确判别92.3%的雌性和87.5%的雄性个体。髋臼的形态差异主要分布于月状面的后上部,即与髋臼切迹相对的月状面区域的宽度表现为雄性大于雌性,另外雄性髋臼大小的波动范围也比雌性更广。造成髋臼性别二态性的生物学原因可能与其功能有关,髋臼作为髋关节的组成部分,起着支撑身体和协同运动的功能,能够优化关节接触面的压力分布。推测雄性髋臼受到的体质量压力更大可能是雄性进化出比雌性更宽大的月状面的主要原因。  相似文献   

2.
快速准确地鉴定两性同型鸟类个体性别在鸟类生态学研究中具有重要意义。本文选择2008年春季迁徙期在崇明东滩停歇的大滨鹬(Calidris tenuirostris)、红腹滨鹬(C.canutus)、红颈滨鹬(C.ruficollis)、尖尾滨鹬(C.acuminata)及翘嘴鹬(Xenus cinereus)5种两性同型的鹬类,用分子生物学方法进行性别鉴定,并基于个体的形态特征(体重、翅长、喙长、头喙长及跗跖长)采用判别分析方法对性别进行判定。结果表明,尖尾滨鹬雄性各形态特征均显著大于雌性,其他4种鹬类则相反。5种鹬类形态特征的性别差异指数在0.5%~25.3%之间,重叠度在29.4%~98.6%之间。5种鹬类判别分析判定性别的准确率在(0.69±0.06)~(0.96±0.01)之间,其中,尖尾滨鹬判别准确率(0.96)最高,翘嘴鹬判别准确率(0.69)最低。形态特征在两性间的差异程度影响性别的判别准确率。另外,两性性比对性别判别的准确率也有影响:性比偏雄性鸟类的雄性判别准确率高于雌性,而性比偏雌性鸟类的雌性判别准确率高于雄性。采用判别分析估测的性比与分子生物学鉴定结果相似,表明判别分析在判定种群的性比方面具有较高的可靠性。  相似文献   

3.
为研究藏羚羊初生性别比例,判断母羊怀孕期间有无偏性选择孕育过程,根据藏羚羊繁殖特点,在可可西里自然保护区卓乃湖藏羚羊产羔地收集到116份藏羚羊胎盘样品,阿尔金山兔子湖产羔地收集到32份胎盘样品,参照文献中对牛科动物进行性别鉴定的3对特异性引物,利用分子生物学方法对样品性染色体类型进行鉴定,从而得到藏羚羊新生羊羔的性别,即藏羚羊初生性比。结果显示,148份藏羚羊胎盘样品中共有雌性76头,雄性72头,初生性比为1︰1.06,经χ~2检验,差异不显著(P=0.742),说明藏羚羊初生性比未明显偏离理论值1︰1。以上研究表明,雌性藏羚羊在怀孕期间无偏性选择作用或这种选择作用非常微弱,不足以影响藏羚羊种群性别比例;而且,利用胎盘对藏羚羊进行初生性比研究是可行的,其他有类似繁殖模式的野生动物也可用此方法研究其初生性比。  相似文献   

4.
利用光学显微镜对蹄盖蕨科15种植物的叶表皮形态特征进行观察和研究。结果表明:蹄盖蕨科15种植物的上、下表皮细胞均为无规则型,垂周壁为凹凸状或深波状;上表皮细胞长宽比在1.0~3.2之间,下表皮细胞长宽比在1.0~2.6之间;在这15种植物中共观察到6种气孔器类型,即极细胞型、腋下细胞型、聚合极细胞型、聚腋下细胞型、无规则四细胞型和无规则型,每种植物具有3~4种气孔器类型,气孔均为下生型,多呈椭圆形。气孔的长宽比在1.3~2.1之间;气孔密度在32~90个/mm2之间;气孔指数为17.7%~40.9%。依据上述叶表皮形态特征将15种蹄盖蕨科植物分为3类,即双盖蕨类、蹄盖蕨类和对囊蕨类。该研究在一定程度上支持Christenhusz分类系统对蹄盖蕨科的划分,为蹄盖蕨科植物的系统分类及演化研究提供基础资料。  相似文献   

5.
通过测定、计算获得40个切花菊品种叶片的6个定性分级性状及叶片的长宽比、尖削度、裂片长宽比、裂片开张度等14个叶形结构参数。以6个定性分级性状为变量,用聚类法选取叶形相似性大的18个切花菊品种,通过多元判别分析法对18个品种叶片的形态结构参数进行数值化鉴别。结果表明,18个叶形相似的品种多元判别的平均拟合率为88.28%,达到了判别品种的目的。说明根据叶形的测量数据能对切花菊品种进行有效鉴别。  相似文献   

6.
本文对48份甘蔗品种(系)的叶片形态特征进行主成分、聚类和判别分析.结果表明,品种(系)间的叶片形态特征差异达到极显著水平(P>0.01);主成分分析选出了3个主成分,方差累积贡献率达到97.52%,叶长、叶宽及形态因子分别是第一、二、三主成分的主导因子;在聚类分析基础上用判别分析选出对甘蔗品种(系)叶片形态分类有极显著影响的面积、长度、宽度、周长、长宽比及形态因子参数,同时建立了4个判别能力较高的判别模型.  相似文献   

7.
目的:观察性别对小鼠H22腹水型肝癌生长情况的影响,研究不同性别动物对肝癌耐受性的差异。方法:取30只8周龄昆明鼠,雌雄各半,随机分为四组,实验组每组10只,对照组每组5只,腹腔接种小鼠H22肝癌细胞,建立小鼠H22腹水型肝癌模型。每天测量小鼠体重并记录生存时间,直至实验组小鼠全部死亡,比较性别因素对小鼠H22腹水型肝癌的生存期是否存在差异。结果:小鼠接种瘤细胞后,逐渐产生腹水,体重增加。雌性小鼠的体重增加比雄性小鼠显著,P=0.049。雄性小鼠生存后期体重出现下降,呈明显恶液质状态。雌性小鼠的体重、腹水增加虽然较雄性动物明显,但生存期却并不少于雄性鼠,反而比雄性小鼠略长,P=0.1567。结论:性别对小鼠H22腹水型肝癌的生长有一定的差异,雌性小鼠的耐受性优于雄性小鼠。  相似文献   

8.
为了解蛇鮈雌雄间是否存在显著的外部形态差异及雌性个体生殖力情况, 在繁殖期对嘉陵江下游(合川江段)共76尾蛇鮈样本的两性异形、性比及雌性个体生殖力进行分析.结果表明: 嘉陵江下游蛇鮈繁殖群体的性比接近1∶1,且蛇鮈两性的体型大小相同,但局部特征(如头部和躯干部等)呈现出显著的两性异形,如成体雄性蛇鮈的头部、胸鳍和腹鳍均较雌性蛇鮈大,而躯干部的体宽、体高和躯干长则是雌性蛇鮈大于雄性蛇鮈,这可能是性选择长期作用的结果.主成分分析显示,前3个主成分的累积贡献率达75.2%,但雌雄个体间形态特征相互重叠,无法将两者截然分开;利用判别函数对蛇鮈性别进行回判,综合判别准确率为92.1%.蛇鮈雌性个体绝对生殖力在979~19979粒;且与体长和去内脏体质量均呈显著正相关.同历史资料相比,本研究中嘉陵江蛇鮈的生殖力增大显著,这可能是蛇鮈对种群资源量下降和水环境变化主动适应的结果.  相似文献   

9.
性双型的特征通常被认为产生于种内争夺交配优先权的斗争。例如,现生和化石的雄性长鼻类动物具有较大的体型和较粗壮的上门齿。本研究阐释了如下现象:化石象型类动物(Elephantiformes,长鼻类的主要类群)一些性双型特征与其进化历史具有相关性,而与性别竞争并非直接相关。在中新世的葛氏铲齿象(Platybelodon grangeri)和狭齿嵌齿象(Gomphotherium angustidens)中,雄性比雌性倾向于具有进化中更进步的特征,如同雄性在进化中领先雌性一步。这种现象可能与雌性偏好的机制相耦合。在象型类动物进化的早期(繁荣期),性别选择压促使雄性比雌性产生更加显著的进步特征;然而,在它们进化的晚期(衰退期),性别选择压似乎减弱,性别的异时进化也减少。这种新的发现或许在大型有蹄类的演化过程中有一定的普遍意义,因为那些繁荣的类群中通常性双型显著,如鹿科和牛科;而衰落的类群中通常性双型不显著。  相似文献   

10.
雌雄异株的大戟科植物中叶片大小和形状的性别差异 作为自然选择的对象,叶片大小和形状能够发挥适应性作用,并且随叶龄而改变。在雌雄异株的植物中,叶片大小和形状因性别而不同,在大多数情况下,雌性的叶片较大。以往研究表明,Adriana tomentosa在叶裂方面存在性别差异。在本研究中,我们探讨了在叶片大小、形状和生理生态等方面是否存在其他性别差异,以及这些差异是否与A. tomentosa的性别适应性和繁殖作用有关。我们测定了生 长在澳大利亚东部的两个不连续种群的雌性和雄性植物的幼叶和老叶的物理化学特征,主要包括:叶面积、周长、锯齿、圆形度、长宽比、圆度以及生态生理指标,包括SLA、干物质质量、叶片水分、RWC、δ 13C、δ 15N同位素比、碳氮含量和碳氮比。同时还测定了叶裂、叶片损伤程度和光合色素含量。在这两个种群中,植物性别显著影响几乎所有与叶片形态相关的参数,如面积、周长、圆形度、长宽比和圆度。与预期相反,我们发现两个种群的雄性具有较大的叶面积且与叶龄无关。雄叶裂片较多,周长较长,但它们较少伸长且锯齿较少。雌性和雄性叶片的生理生态指标差异不大。叶片损伤程度因性别而异,但也因种群而异。叶面积和叶形在性别间的差异不能被生理生态因素所补偿。然而,叶面积可能由其他与叶片形态相关的生理生态机制补偿,因为与雄性相比,雌性的叶面积较小,但叶片锯齿较大。  相似文献   

11.
大熊猫粪便宽径与咬节平均长度的关系   总被引:1,自引:1,他引:0  
粪便咬节是大熊猫数量调查中最常用的指标。然而,大熊猫在主食竹叶的季节有时在粪便中未留下咬节而使数量调查难以进行。为此,本文对大熊猫粪便宽径与咬节平均长度的关系进行了初步探讨。结果表明,大熊猫粪便宽径呈正态分布,同一个体的含咬节粪便与全由竹叶组成的粪便在宽径上无显著差异。大熊猫咬节平均长度与粪便宽径存在显著的回归关系。在不考虑年龄的情况下,粪便咬节平均长度与粪便宽径的回归方程为:Y=0.38X十14.40。成体和亚成体组的粪便咬节平均长度与粪便宽径的回归方程为:Y=0.22 X+22.79。年龄对大熊猫粪便咬节平均长度与粪便宽径的回归关系有显著影响。  相似文献   

12.
Extraction of DNA from non-invasive samples (feces) has been used increasingly in genetic research on wildlife. For effective and reliable genetic analyses, knowledge about which samples should be selected in the field is essential. For this reason, we examined the process of DNA degradation in feces of deer. We collected fresh fecal pellets from three wild deer living in a warm temperate forest. We then assessed the effects of time (3, 5, and 10 days) under three environmental conditions (on the forest floor, on exposed ground, and inside the laboratory) on the rates of correct genotyping (CG), amplification failure (NA), genotyping error among positive amplification (ER), false alleles (FA), and allelic dropout (AD) of 15 microsatellite loci. The rate of CG significantly decreased, and those of NA and FA increased with increasing lapse of time. Rates of CG tended to be highest and those of NA, ER, FA, and AD to be lowest in feces kept inside, followed by those on the forest floor. Suitability of samples for DNA extraction was lowest in fecal pellets left on exposed ground, and we suspect that rain may hasten DNA degradation. NA rate could serve as a reliable indicator of the quality of fecal pellets because it was significantly positively correlated with ER rate. For efficient genetic analyses using deer feces in warm temperate zones, we recommend collecting fecal pellets within 3 days of defecation, during periods without rainfall and from under the cover of trees.  相似文献   

13.
Genetic studies of wild animal populations are often hindered by difficulties in obtaining blood samples. Recent advances in molecular biology have allowed the use of noninvasive samples as sources of DNA (e.g., hair or feces), but such samples may provide low-quality DNA and prevent the determination of true genotypes in subsequent DNA analysis. We present a preliminary study aimed at assessing the reliability of using fecal samples for genotyping in Barbary macaques (Macaca sylvanus). The test was performed on samples of blood and feces from 11 captive animals, using three dinucleotide microsatellites. The CTAB DNA extraction method was found to be the most relevant for Barbary macaque feces, yielding successful amplification at all loci for 70% of PCRs. All the fecal samples tested gave correct genotypes at least once for each locus when referenced against blood-derived genotypes. An average of 18.3% of PCRs displayed spurious genotypes (false homozygous or false allele). The minimum theoretical probability required to obtain a 100% accurate genotype is 0.74, based on the criterion that a correct genotype is assessed only if it was observed at least twice. The observed probability of obtaining a correct genotype from three PCRs, based on our genotyping results, was greater (0.81 on average) than the minimum threshold. In conclusion, our comparison of blood and fecal samples showed that fecal sampling is a reliable tool for the further study of wild Barbary macaque populations.  相似文献   

14.
The Korean long-tailed goral (Naemorhedus caudatus) is at risk of population decline due to habitat loss and fragmentation. Therefore, it is essential to ascertain its presence and/or the identity of individuals of the goral using non-invasive fecal samples for its conservation and management. In this study, we examined the morphology of fecal samples to provide the baseline data that can be used to distinguish species and age of goral individuals. We detected a significant difference in the length-to-width ratios of feces among the five ungulate species found in Korea. Also, we detected a significant difference in the length-to-width ratios of feces of gorals depending on the age groups. To assess the accuracy of species and age identification based on the fecal morphology, we conducted a series of blind comparison between the mean length-to-width ratios of the fecal pellets and the reference mean ratio values of the fecal pellets. Using 20 fecal pellets, our results showed 73%–86% probability of correct identification of the three species (gorals, goats, and roe deer), and 83%–90% probability of correct identification of >5 year-old goral individuals. The use of fecal morphometric analyses will be useful for the studies of Korean ungulate species, particularly the endangered gorals.  相似文献   

15.
《农业工程》2014,34(1):13-18
The black muntjac (Muntiacus crinifrons), endemic to China, was categorized as a Grade I National Key Protected Animal by the Ministry of Agriculture of China and classified as Vulnerable (VU) by IUCN. Recent years, studies had been conducted on this species mainly focusing on habitat selection, food habit, gene flow etc., only with a few reports on the population dynamics. Individual identification of wild animals is one of the most important subjects in the population dynamic research. Of various molecular markers, microsatellite DNA fingerprinting has been used most frequently and successfully on many kinds of animals. Here, we constructed identification system for the black muntjac using 8 microsatellite loci. 31 black muntjacs were identified from 141 fecal samples, whereas 43 samples could be used for PCR after repeated trials. Further, the sequencing for Cytb gene was also conducted for convincing us the identity of fecal samples. The results, highly consistent between sequencing consequence and sequence data from Genebank, implied that those experienced local people are of the convincing knowledge about wild animals, especially at the respects of identification to black muntjac’ feces pellets. Moreover, we detected the specificity of identification system to black muntjac. BM1225 was the only one locus that unsuccessful PCR for the muscle samples of Muntiacus reevesi was observed, which suggested that our identification system could be used for excluding the non-researched objects in some cases. Analyses using softwares CERVUS 3.0 and POPGENE 1.21 showed that the present identification system had strong discrimination power: 0.938 per loci (DP) or 0.999 in total (CDP). The mean observed number of alleles (Na), mean effective number of alleles (Ne), and mean excepted heterogosity (He) were 8.875, 6.375, and 0.829 respectively. Considering that the change of sex ratio in population could exert significant impact on population growth, density to some extent, we also analyzed the sex ratio of those individuals that had been identified based on fecal samples from filed using SRY (Sex-determining region Y) gene amplification, which identified 19 males and 12 females.  相似文献   

16.
Non-invasive wildlife research using DNA from feces has become increasingly popular. Recent studies have attempted to solve problems associated with recovering DNA from feces by investigating the influence of factors such as season, diet, collection method, preservation method, extraction protocol, and time. To our knowledge, studies of this nature have not addressed DNA degradation over time in wet environments, and have not been performed on fecal pellets of ungulates. Therefore, our objective was to determine the length of time a fecal pellet from a Sitka black-tailed deer (Odocoileus hemionus sitkensis) could remain in the field in a temperate rainforest environment before the DNA became too degraded for individual identification. Pellets were extracted from the rectum of recently killed deer and placed in an environment protected from rainfall and in an environment exposed to rainfall. Pellets from each treatment group were sampled at intervals of 2, 7, 14, 21, and 28 days after deer harvest. DNA was extracted from sampled pellets and individual samples were genotyped using microsatellite markers. Amplification failure and errors (dropout and false alleles) were recorded to determine extent of DNA degradation. Eighty percent of samples in the protected environment and 22% of samples in the exposed environment were successfully genotyped during the 28-day experiment. With no samples being successfully genotyped in the exposed environment after 7 days, our study showed that rainfall significantly increases degradation rates of DNA from ungulate pellets.  相似文献   

17.
张立  房继明  孙儒泳 《兽类学报》2001,21(4):292-300
研究了成年布氏田鼠在10min内,对不同光照周期下(长光照:LD;短光照:SD)陌生雌/雄个体尿液和粪便两种单一个体气味源的气味行为反应,实验发现:所有雌雄被试鼠对LD气味源比SD气味源表现出更多的嗅闻行为。LD和SD被试鼠对同性/异性尿液气味的嗅闻行为没有表现出明显的差别,但LD被试雄鼠对陌生雌鼠粪便的嗅闻频次显多于SD被试雄鼠,从嗅闻行为特征量(嗅闻行为占所有行为的百分比)来看,所有LD和SD被试雌,雄鼠对尿液的嗅 明显多于粪便,除SD粪便气味外,被试鼠对异性气味源的嗅闻明显多于同性,实验结果表明:作为两种个体气味源,尿液和粪便都带有季节性信息,而且是具有性别特性的。异性的个体气味源比同性的个体气味源更具吸引力;长光照动物的个体气味比短光照动物的气味更具吸引力。  相似文献   

18.
BacteroidesPrevotella group is one of the most promising targets for detecting fecal contamination in water environments, principally due to its host-specific distributions and high concentrations in feces of warm-blooded animals. We developed real-time PCR assays for quantifying chicken/duck-, chicken-, and duck-associated BacteroidesPrevotella 16S rRNA genetic markers (Chicken/Duck-Bac, Chicken-Bac, and Duck-Bac). A reference collection of DNA extracts from 143 individual fecal samples and wastewater treatment plant influent was tested by the newly established markers. The quantification limits of Chicken/Duck-Bac, Chicken-Bac, and Duck-Bac markers in environmental water were 54, 57, and 12 copies/reaction, respectively. It was possible to detect possible fecal contaminations from wild ducks in environmental water with the constructed genetic marker assays, even though the density of total coliforms in the identical water samples was below the detection limit. Chicken/Duck-Bac marker was amplified from feces of wild duck and chicken with the positive ratio of 96 and 61 %, respectively, and no cross-reaction was observed for the other animal feces. Chicken-Bac marker was detected from 70 % of chicken feces, while detected from 39 % of cow feces, 8.3 % of pig feces, and 12 % of swan feces. Duck-Bac marker was detected from 85 % of wild duck feces and cross-reacted with 31 % of cow feces. These levels of detection specificity are common in avian-associated genetic markers previously proposed, which implies that there is a practical limitation in the independent application of avian-associated BacteroidesPrevotella 16S rRNA genetic markers and a combination with other fecal contamination markers is preferable for detecting fecal contamination in water environments.  相似文献   

19.
The modified Baermann funnel technique was evaluated to determine the effects of time of baermannization, fecal preparation, type and size of funnel, and type of filter on the number of first stage larvae of Protostrongylus spp. recovered from feces of Rocky Mountain bighorn sheep (Ovis canadensis). More larvae were recovered when fecal pellets were baermannized for 24 hr compared to 8 hr, and when feces were crushed than when left intact. Use of small funnels resulted in the recovery of more larvae per gram of feces than larger funnels, and glass funnels more than plastic ones. There was no difference in recovery of larvae between cheesecloth filters and cellulose filters.  相似文献   

20.
Li  Guiding  Jiang  Yi  Li  Qinyuan  An  Defeng  Bao  Mingwei  Lang  Lei  Han  Li  Huang  Xueshi  Jiang  Chenglin 《Antonie van Leeuwenhoek》2022,115(9):1187-1202

Asian elephant is large herbivorous animal with elongated hindgut. To explore fecal microbial community composition with various ages, sex and diets, and their role in plant biomass degrading and nutrition conversation. We generated 119 Gb by metagenome sequencing from 10 different individual feces and identified 5.3 million non-redundant genes. The comprehensive analysis established that the Bacteroidetes, Firmicutes and Proteobacteria constituted the most dominant phyla in overall fecal samples. In different individuals, the alpha diversity of the fecal microbiota in female was lower than male, and the alpha diversity of the fecal microbiota in older was higher than younger, and the fecal microbial diversity was the most complex in wild elephant. But the predominant population compositions were similar to each other. Moreover, the newborn infant elephant feces assembled and maintained a diverse but host-specific fecal microbial population. The discovery speculated that Asian elephant maybe have start to building microbial populations before birth. Meanwhile, these results illustrated that host phylogeny, diets, ages and sex are significant factors for fecal microbial community composition. Therefore, we put forward the process of Asian elephant fecal microbial community composition that the dominant populations were built first under the guidance of phylogeny, and then shaped gradually a unique and flexible gut microbial community structure under the influences of diet, age and sex. This study found also that the Bacteroidetes were presumably the main drivers of plant fiber-degradation. A large of secondary metabolite biosynthetic gene clusters, and genes related to enediyne biosynthesis were found and showed that the Asian elephant fecal microbiome harbored a diverse and abundant genetic resource. A picture of antibiotic resistance genes (ARGs) reservoirs of fecal microbiota in Asian elephants was provided. Surprisingly, there was such wide range of ARGs in newborn infant elephant. Further strengthening our speculation that the fetus of Asian elephant has colonized prototypical fecal microbiota before birth. However, it is necessary to point out that the data give a first inside into the gut microbiota of Asian elephants but too few individuals were studied to draw general conclusions for differences among wild and captured elephants, female and male or different ages. Further studies are required. Additionally, the cultured actinomycetes from Asian elephant feces also were investigated, which the feces of Asian elephants could be an important source of actinomycetes.

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