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1.
应用阴茎骨鉴定雄性褐家鼠年龄组的探讨   总被引:4,自引:2,他引:2  
1986年10—11月,作者在长春市研究了城市褐家鼠的种群生态。获得标本 1,214号(531,683),解剖、测量、记录了雄性睾丸重量、长度和宽度,制取了雄性阴茎骨。对其种群阴茎骨长度作了分析,并依据阴茎骨长度作褐家鼠的频数分配,对照体长、体重、睾丸及头骨等特征,划分5个年龄组。分析结果表明,应用雄性褐家鼠阴茎骨划分年龄组,其组间差异显著,组间交叉不大,相对准确,能比较接近实际年龄,故用阴茎骨长度作为划分褐家鼠种群年龄组标准是可行的。  相似文献   

2.
海南坡鹿种群生活史特征及种群动态趋势预测   总被引:1,自引:1,他引:0  
本文应用生命表和Leslie矩阵等生活史常规研究方法,分析了生存于海南邦溪自然保护区的国家I级珍稀濒危哺乳动物海南坡鹿种群的年龄结构、特定年龄存活率、特定年龄繁殖率、初次产仔年龄、产仔季节、性比、寿命等重要生活史特征,并预测其种群动态趋势.邦溪海南坡鹿种群平均寿命4.6岁,雌性平均寿命略高于雄性,分别为4.7岁,4.4岁;雌性平均初次产仔年龄为24月龄;雌性平均性成熟年龄为16月龄;雌性最长繁殖寿命为8.5岁,雄性最长繁殖寿命约为4岁;成年雌性平均一年一胎,胎仔数为1;新生幼仔数量雄性大于雌性,性比为1.33∶1;种群动态生命表的分析结果表明,各年龄段雄性存活率高于雌性.幼体(0~2岁)死亡数雌性高于雄性,壮年成体(3~8岁)死亡数雄性高于雌性,老体(9岁~)死亡数两性几乎相等.雌性幼体受到较强的自然选择作用,体弱个体被淘汰;壮年雄体为繁殖付出较高的代价,死亡个体数量较高.Leslie矩阵预测结果表明,如果影响出生率和死亡率的因子不变,种群数量将逐年增长,周限增长率为λ≈1.011; 种群内禀增长率r≈0.012;种群世代增长率R0 ≈1.06;世代长度T≈5.12年.产仔时间为秋季与冬季,春、夏季节不产仔,此为适应海南岛独特的热带环境选择压力的结果.  相似文献   

3.
目的:塔里木马鹿(Cervus elaphus yarkandensis)为马鹿的新疆特有亚种,自20世纪50年代以来,由于自然和人为因素影响,种群数量急剧下降,现已隔离成3个孤立的小种群,即沙雅种群、尉犁种群和且末种群.为了更好地保护这一濒危野生动物.方法:基于塔里木马鹿线粒体控制区部分序列对3个种群的控制区结构和遗传多样性进行了研究.结果:在34个序列比对中得到342bp的片段,含变异位点12个,占分析序列长度的3.51%,由此定义了6个单倍型.显示出3个种群总的核苷酸多样性较低(0.01351±0.00063),单倍型多样性较高(0.693±0.051);就单个种群而言,且末种群的遗传多样性最低,而沙雅种群最高.从Tajima's D和Fu and Li's D值的估算结果来看,塔里木马鹿尉犁和沙雅种群相对于中性进化的歧异度并没有明显的偏离(P>0.1),且末种群则出现了明显的偏离(分别为P<0.05和P<0.02),这预示着3个塔里木马鹿种群间可能存在一定的平衡选择.分子变异分析表明,沙雅和尉犁种群间基因流Nm大于4,说明这2个塔里木马鹿种群间存在着非常丰富的基因流,且末种群分别与沙雅、尉犁种群间基因流Nm均小于1,而且末种群分别与沙雅和尉犁种群产生了明显的遗传分化(Fst分别为0.409;0.718,P值均小于0.001),以及3个塔里木马鹿种群单倍型间的序列差异为0.012.结论:以上数据都显示了3个塔里木马鹿种群的单倍型间已经出现了明显分化.结合系统发生关系分析,应将沙雅种群和尉犁种群联合建立管理单元进行重点保护.  相似文献   

4.
崔亮伟  钟泰  肖林  肖文 《动物学研究》2006,27(4):337-343
介绍了应用过夜地粪便来估计白马雪山黑白仰鼻猴群大小和组成的一种方法。该物种以单雄多雌单元和全雄组的形式在树上过夜。粪粒根据其大小可分为3种类型成年雄性的(最大)、成年雌性的(中等大小)和未成年个体的(最小)。2000—2001年,搜集了滇西北白马雪山国家级自然保护区北部南任村(99°04′E,28°34′N)附近黑白仰鼻猴群每个季节2个过夜地的粪粒。根据2001年11月猴群通过开阔地的数据来确定猴群组成。每个季节,由于单雄多雌单元的成年个体数与其粪粒数正相关,所以二者回归直线的斜率可以看作是每个个体每晚的平均排便量。由于该物种的栖息地主要为高山峡谷,而且能见度较低,因此,利用过夜地粪便比以前通过猴群活动痕迹来估计猴群大小和组成相对准确、可靠。从估计成年雌性个体数的角度看,利用粪粒来估计种群大约有9·4%的偏差。导致偏差的可能原因有杂草和灌丛对粪粒准确计数的影响、个体排粪率的差异以及成年雄性最小粪粒与成年雌性最大粪粒的混淆等。该方法适应于栖息地和主要食物与本文研究种群相似的其他种群。  相似文献   

5.
灰鼠的年龄鉴定及种群组成   总被引:1,自引:0,他引:1  
灰鼠(Sciurus vulgaris)是我国重要毛皮兽之一。为了更好的利用,掌握其种群动态规律是必要的。种群年龄组成是种群动态特征之一。因而,对灰鼠种群年龄的研究,有一定的意义。有关灰鼠年龄的研究报道不多。国外对黑松鼠(Sciurus niger)、北美灰松鼠(S.carolinensis)的年龄组划分吋,多以长骨骺骨的骨化程度、雄性阴茎骨的形态特征及其重量和长度的差异、水晶体的干重、尾毛的特征等作为指标的依据(Petrides 1951; Carson1961; Kirkpatrick等1957; Beale 1962),但年龄组划分的结果,多限于成年与幼年两组,  相似文献   

6.
崔亮伟  钟泰  肖林  肖文 《动物学研究》2006,27(4):337-343
介绍了应用过夜地粪便来估计白马雪山黑白仰鼻猴群大小和组成的一种方法。该物种以单雄多雌单元和全雄组的形式在树上过夜。粪粒根据其大小可分为3种类型:成年雄性的(最大)、成年雌性的(中等大小)和未成年个体的(最小)。2000—2001年,搜集了滇西北白马雪山国家级自然保护区北部南任村(99°04′E, 28°34′N)附近黑白仰鼻猴群每个季节2个过夜地的粪粒。根据2001年11月猴群通过开阔地的数据来确定猴群组成。每个季节,由于单雄多雌单元的成年个体数与其粪粒数正相关,所以二者回归直线的斜率可以看作是每个个体每晚的平均排便量。由于该物种的栖息地主要为高山峡谷,而且能见度较低,因此,利用过夜地粪便比以前通过猴群活动痕迹来估计猴群大小和组成相对准确、可靠。从估计成年雌性个体数的角度看,利用粪粒来估计种群大约有9.4%的偏差。导致偏差的可能原因有杂草和灌丛对粪粒准确计数的影响、个体排粪率的差异以及成年雄性最小粪粒与成年雌性最大粪粒的混淆等。该方法适应于栖息地和主要食物与本文研究种群相似的其他种群。  相似文献   

7.
家养有蹄类动物的反刍行为已有大量研究,而受限于野外条件,野生有蹄类动物反刍行为的研究有限。以往研究认为,体型可能是影响动物反刍行为的重要因素。本研究以日本奈良公园日本梅花鹿Cervus nippon nippon和中国江苏大丰麋鹿Elaphurus davidianus为研究对象,观察记录并比较分析了发情期的日本梅花鹿与发情期的麋鹿在卧息时反刍行为的种内及种间差异。按照年龄性别差异,分5种类型(成年雄性、成年雌性、亚成雄性、亚成雌性和幼鹿)研究两物种食团咀嚼时间、咀嚼频率和咀嚼速率的差异。结果表明,1)日本梅花鹿的咀嚼速率和食团咀嚼时间受性别-年龄的显著影响:咀嚼速率为幼体>亚成雌性>亚成雄性>成年雌性>成年雄性,而食团咀嚼时间为成年雄性>亚成雄性>成年雌性>亚成雌性>幼体;2)性别-年龄对麋鹿咀嚼频率有显著的影响,成年雄性<成年雌性<亚成雄性<亚成雌性<幼体;3)两物种在咀嚼频率、食团咀嚼时间和咀嚼速率上的差异均有统计学意义,体型更大的麋鹿咀嚼速率更慢,食团咀嚼时间更长。与体型相关的性别及年龄显著影响了日本梅花鹿和麋鹿的反刍行为。  相似文献   

8.
为了揭示孤雌生殖型稻水象甲不同种群触角的形态变异,明确两性生殖型与孤雌生殖型稻水象甲触角形态特征差异。分析了来自于吉林通化(TH)、吉林公主岭(GZL)、辽宁沈阳东陵区(DL)、辽宁沈阳苏家屯(SJT)、山东东营(DY)5个孤雌生殖稻水象甲触角各节的长度和最大宽度,并与美国两性生殖型稻水象甲成虫触角进行了比较。结果表明孤雌生殖型雌性的触角柄节长度、触角总长度明显长于两性生殖型雌性的(P0.01)。除柄节外,孤雌生殖型雌性触角各节的宽度均明显宽于两性生殖型雌性(P0.01)。两种生殖型稻水象甲雌性触角梗节以及第3、4、6鞭小节的最大宽度范围不重叠。吉林通化种群(TH)与其他4个中国北方种群之间触角有显著性差异。两性生殖型稻水象甲雄性的触角总长度和柄节长度均明显长于雌性(P0.01),且雄性柄节长度范围(310.45-316.22μm)与雌性的范围(282.12-294.56μm)不重叠。结果提示,柄节长度可以鉴别本研究中两性生殖型稻水象甲雌雄个体;触角梗节以及第3、4、6鞭小节的最大宽度范围可以鉴别本研究中2种生殖型雌性个体。  相似文献   

9.
新疆塔里木马鹿粪便激素含量季节性变化的初步研究   总被引:3,自引:0,他引:3  
目的:检测雄性塔里木马鹿的睾酮,雌鹿的雌二醇、雌三醇、孕酮等粪便激素含量,并比较不同月份之间的变化。方法:利用放射免疫分析法(RIA)在且末和尉犁县马鹿场采集塔里木马鹿粪便,检测了2004年2~12月间塔里木马鹿粪便中的激素水平。结果:粪便性激素水平有明显的季节变化(P<0.05)。雄鹿粪便睾酮水平月间差异显著(P<0.05),浓度在8月有2个高峰。雌鹿粪便雌二醇在3月和6月有2个高峰;粪便孕酮水平在3月有2个高峰,在8月有1个高峰;雌三醇差异不显著,但4月的最高值也显著高于其他各时间点(P<0.05)。结论:利用动物粪便研究激素具有对保护动物完全无伤害、材料收集容易等优点,并且有助于评估动物青春期的健康状况、判断动物排卵方式、早孕检查、产前预测等,因而是目前研究野生珍稀动物性激素的一种较为理想的方法。  相似文献   

10.
北山羊(Capra sibirica)是一种主要分布于中亚高山地带的有蹄类物种,中国国家I级重点保护野生动物。北山羊选择陡峭悬崖作为栖息地,采食集中于禾本科和莎草科植物。北山羊具有典型的雌雄异形现象,雄性体型大于雌性。除交配期外,成年雌雄个体之间同性集群现象明显。近年来,由于偷猎、栖息地丧失和疾病等原因的影响,北山羊种群数量不断减少。为保护此物种,国内外学者针对北山羊开展了大量研究。本文从种属划分、形态与生理、种群密度和数量、生境选择、时间分配与活动节律、集群、濒危原因与保护对策等方面对北山羊的研究现状进行了综述,分析亟待深入研究的内容,北山羊同性集群及食性研究应是下一步工作重点。  相似文献   

11.
By examining the morphometry (i.e., length, width, length‐to‐width ratio, and volume) of pellets in three different categories (adult males, adult females, and yearlings) mule deer (Odocoileus hemionus), we were able to distinguish via discriminant function and fuzzy clustering analyses the age and sex of these animals. To determine a priori the identity of the pellet samples and evaluate the accuracy of our methods, we obtained samples from individuals in captivity. The discriminant function allowed us to correctly assign 100% of adult males, 91.66% of adult females, and 75% of yearlings to an age class, using previous information. The fuzzy clustering method enabled us to correctly distinguish 100% of adult males, 83.3% of adult females, and 75% of yearlings. The methods are based upon different assumptions. An important assumption with the discriminant function method is that the membership of each pellet group must be established a priori. This may be a disadvantage in certain cases, such as when pellet samples are gathered for an indirect population assessment procedure. Despite this drawback, however, both methods appear to be highly accurate. Zoo Biol 23:139–146, 2004. © 2004 Wiley‐Liss, Inc.  相似文献   

12.
新疆马鹿塔里木亚种的现状与保护   总被引:14,自引:1,他引:13  
新疆马鹿塔里木亚种高度适应荒漠生境,自20世纪50年代以来,由于自然和人为因素的影响,种群数量急剧下降。栖息地退缩和片段化不仅导致种群遗传多样性的丧失,而且也因遗传漂变和近亲繁殖,不断地加剧了该亚种的濒危程度。为有效的保护该物种,特提出可行的保护措施建议。  相似文献   

13.
In polygynous, sexually dimorphic species, sexual selection should be stronger in males than in females. Although this prediction extends to the effects of early development on fitness, few studies have documented early determinants of lifetime reproductive success in a natural mammal population. In this paper, we describe factors affecting the reproductive success of male and female red deer (Cervus elaphus) on the island of Rum, Scotland. Birthweight was a significant determinant of total lifetime reproductive success in males, with heavier-born males being more successful than lighter ones. In contrast, birthweight did not affect female reproductive success. High population density and cold spring temperatures in the year of birth decreased several components of fitness in females, but did not affect the breeding success of males. The results confirm the prediction that selection on a sexually dimorphic trait should be greater in males than in females, and explain the differential maternal expenditure between sons and daughters observed in red deer. Differences between the sexes in the effects of environmental and phenotypic variation on fitness may generate differences in the amount of heritable genetic variation underlying traits such as birthweight.  相似文献   

14.
Overhunting of red deer (Cervus elaphus) in eastern Switzerland led to its extinction in the second half of the 17th century. Natural recolonization must have taken place later, because red deer were seen again in the canton of the Grisons (eastern Switzerland) in the 1870s. According to historical data, three different populations could have served as the source population. To determine the genetic origin of the eastern Swiss red deer population, we collected samples from five different subpopulations in the canton of the Grisons as well as from four adjacent populations in Germany, Liechtenstein, Austria, and Italy. We analyzed the samples by genotyping 18 microsatellite loci. F(ST) values, assignment tests, correspondence analysis, and fuzzy clustering clearly pointed to Liechtenstein as the most probable source population for the red deer in eastern Switzerland. In addition, our analyses revealed high gene diversity in all examined populations. Gene flow and the high genetic admixture are discussed.  相似文献   

15.
Breeding dispersal can be of significant ecological and evolutionary importance. Yet, it is seldom considered in mammals. I present data on male red deer (Cervus elaphus) movements between sub-populations in southern Sweden during the rut. I investigated whether these movements could be breeding dispersal driven by mate competition. During the ruts of 1998–2009, I recorded 91 movements of males. The longest movement distance was 18.5 km. Dispersal was not restricted to yearlings or sub-adults, but also observed among adult stags. Of 91 movements observed, 7 were made by yearlings, 46 by sub-adults and 38 by adults. There was a significant move among yearlings and sub-adults towards areas with a higher ratio of females/adult males and towards areas with more females. The movements between rutting areas thereby seemed driven by sexual competition.  相似文献   

16.
Sequences of ITS-1 and ITS-2 rDNA for adult males of Spiculopteragia asymmetrica and Spiculopteragia quadrispiculata in red deer (Cervus elaphus) were determined. They were found to be identical, suggesting that S. asymmetrica and S. quadrispiculata represent a single species and do not refute the concept of dimorphic species in the Spiculopteragia.  相似文献   

17.
保护新疆马鹿塔里木亚种的建议   总被引:1,自引:0,他引:1  
马鹿塔里木亚种分布于新疆塔里木盆地各沿河地带,强度适应荒漠生境。采用分子系统学方法研究表明,世界马鹿分为东西两大系统,马鹿塔里木亚种是我国唯一属于西部系统的亚种。在中国濒危动物红皮书中被列为濒危(E)亚种,按国际自然与自然资源保护联盟(IUCN)1993年制定的世界物种红色名录濒危定级标准,属于极危级(EN)。自20世纪50年代以来,由于自然和人为因素的影响,种群数量急骤下降,现今马鹿塔里木亚种在塔河流域被隔离为莎雅、尉犁和且末3个小种群,当前该亚种正受到栖息地减小和片断化的双重影响,而且因遗传漂变和近亲繁殖的不断增加也进一步加剧它的濒危程度。为有效保护该物种特提出可行的保护建议。  相似文献   

18.
In sexually dimorphic mammals, high population density is commonly associated with increased mortality of males relative to females and with female-biased adult sex ratios. This paper investigates the consequences of these changes on the distribution of male breeding success, the intensity of competition for females and the opportunity for sexual selection. After the red deer (Cervus elaphus L.) population of the North Block of Rum (Inner Hebrides) was released from culling, female numbers rose and male numbers declined, leading to an adult sex ratio of around one male to two females. This change was the result of increased mortality of males relative to females during the first two years of life; of increased emigration rates by young males; and of reduced immigration by males from outside the study area. The increasing bias in the adult sex ratio affected the timing of breeding as well as the distribution of mating success in males. As the adult sex ratio became increasingly biased towards females, the degree of skew in mating success (calculated across all harem-holders) increased, but mature males defended harems for shorter periods and a higher proportion of males held harems. In addition, a higher proportion of calves were fathered by immigrant males and the proportion fathered by males born in the study area declined. These results support the contention that, where high population density is associated with a female-biased adult sex ratio, competition for mates is likely to decline.  相似文献   

19.
A serologic survey revealed that Norwegian populations of free-ranging reindeer (Rangifer tarandus tarandus), roe deer (Capreolus capreolus), red deer (Cervus elaphus), and moose (Alces alces) have been exposed to alpha-herpesviruses and pestiviruses. A total of 3,796 serum samples collected during the period 1993-2000 were tested in a neutralization test for antibodies against bovine herpesvirus 1 (BHV-1) or cervid herpesvirus 2 (CerHV-2), and 3,897 samples were tested by a neutralization test and/or enzyme-linked immunosorbent assay for antibodies against bovine viral diarrhea virus (BVDV). Antibodies against alpha-herpesvirus were found in 28.5% of reindeer, 3.0% of roe deer, and 0.5% of red deer, while all moose samples were negative. In reindeer, the prevalence of seropositive animals increased with age and was higher in males than females. Antibodies against BVDV were detected in 12.3% of roe deer, 4.2% of reindeer, 2.0% of moose and 1.1% of red deer. The results indicate that both alpha-herpesvirus and pestivirus are endemic in reindeer and pestivirus is endemic in roe deer in Norway. The viruses may be specific cervid strains. Seropositive red deer and moose may have become exposed as a result of contact with other ruminant species.  相似文献   

20.
Movements of male white-tailed deer (Odocoileus virginianus) are of great concern with respect to spread of chronic wasting disease (CWD) across landscapes because most yearlings males disperse and adult males have higher prevalence of CWD than do females and younger deer. We radiocollared and monitored 85 male white-tailed deer in the middle Missouri River Valley of eastern Nebraska and western Iowa, USA from 2004 to 2008. Average size (±SE) of fixed-kernel annual home ranges (95%) and core areas (50%) for resident deer were 449 (±32) ha and 99 (±7) ha, respectively. Resident deer exhibited a high-degree of fidelity to their home ranges. Mean overlap between consecutive annual home ranges and core areas was 81% and 74%, respectively. Average dispersal distance was 17.7 ± 4.5 km (range = 3–121 km) for 22 radio-marked and 6 ear-tagged yearlings. Mean spring dispersal distance (25 km) was 150% greater than fall (10 km). Dispersal direction from Desoto National Wildlife Refuge (DNWR) was bimodal on a northwest to southeast axis that followed the Missouri River corridor. Of 22 yearlings that dispersed, 18 (82%) established adult home ranges within the river valley. Dispersal movements of yearling males represent the greatest risk for rapid spread of diseases from infected source populations. Disease management efforts in riparian habitats should target male fawns and yearling males for removal in areas within or immediately adjacent to river corridors. © 2011 The Wildlife Society.  相似文献   

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