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1.
龟鳖类锥虫两新种(动体目:锥体科)   总被引:1,自引:0,他引:1  
龟鳖类锥虫的研究,国内外均比较少。本文记述了在中华鳖和乌龟血液中发现的两新种,鳖锥虫和龟锥虫。这是国内首次对龟鳖类锥虫研究的报道。  相似文献   
2.
本文主要描述池塘养殖条件下鲥鱼幼鱼的生长与食性。1)1987-1989年8月至11月幼鱼生长迅速,快于同期珠江天然个体的生长速度;2)体长26.6-94.9mm的幼鱼主要摄食浮游动物,轮虫和浮游植物出现率随个体增大而减少。食物共有18个属种,摄食频度为100%;3)幼鱼的平均饱满指数为75.70‰。各类食物重量百分比的顺序为:桡足类>枝角类>无节幼体>虾类溞状幼体>轮虫>藻类。  相似文献   
3.
本文主要描述池塘养殖条件下鲥鱼幼鱼的生长与食性。1)1987—1989年8月至11月幼鱼生长迅速,快于同期珠江天然个体的生长速度;2)体长26.6—94.9mm的幼鱼主要摄食浮游动物,轮虫和浮游植物出现率随个体增大而减少。食物共有18个属种,摄食频度为100%;3)幼鱼的平均饱满指数为75.70‰。各类食物重量百分比的顺序为:桡足类>枝角类>无节幼体>虾类溞状幼体>轮虫>藻类。  相似文献   
4.
Home range and habitat use of male Reeves's Pheasant(syrmaticus reevesii)were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve,Henan Province.Results from five individuals of Reeves's Pheasant with over 30 relocations,indicated that the average size of home range was 10.03±1.17 hm2 by Minimum Convex Polygon method.8.60±0.35 hm2 by 90% Harmonic Mean Transformation method,and 9.50±1.90 hm2 by 95% Fixed Kernel method.It was observed that the winter range is smaller than that in the breeding season.The mean core area of the home range was found to be 1.88±0.37 hm2.Although the habitat composition of the core area varied greatly for individuals,a large part of the habitats used were composed of conifer and broadleaf mixed forests,masson pine forests,fir forests,and shrubs.Habitat use within the study area was non-random,while habitats within home ranges were randomly used.Habitat use was dictated by tree diameter at breast height,shrub height and coverage at 2.0 m.The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter.Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve,increasing suitable habitat for Reeves's Pheasant through artificial plantations(e.g.firs),and restoring some parts of the large shrub area into forests.  相似文献   
5.
Phylogenetic relationships of the freshwater turtles of the genus Mauremys and representatives of several other batagurid genera were inferred from variations in 863 base positions of mitochondrial 12S and 16S rRNA genes. Results strongly suggested the non-monophyly of Mauremys by indicating the closest affinity of Mauremys japonica with Chinemys reevesii , the type species of the genus Chinemys . Recent morphological analyses of the batagurid genera suggested that Mauremys is a basal stock of the subfamily Geoemydinae, whereas Chinemys is a member of the subfamily Batagurinae as supported by several putative synapomorphs with other batagurine genera. It is thus probable that the morphological character states used to define Mauremys actually represent symplesiomorphy, and that morphological character states shared between Chinemys and other batagurine genera have resulted from convergence. Also, our results did not support a sister-group relationship between Mauremys annamensis and Mauremys mutica , which has been implicitly or explicitly assumed by a number of previous authors on the basis of morphological data. Instead, M. annamensis was indicated to be closest to Mauremys i versoni , a species assumed to be most divergent among the East Asian Mauremys by previous authors.  相似文献   
6.
乌龟白细胞发育过程的观察   总被引:3,自引:0,他引:3  
通过对乌龟骨髓、脾脏、肝脏等几种组织涂片的观察研究,发现骨髓与脾脏是乌龟的主要造血器官;白细胞的发育过程大致经过三个阶段,即原始阶段、幼稚阶段、成熟阶段。着重描述了各个阶段细胞的形态特征,并对乌龟白血细胞的发育及命名等问题作了初步探讨。  相似文献   
7.
参照人SRY gene HMG-box保守区的序列,设计一对引物,扩增了乌龟的Sox gene,并对扩增条件进行了优化。结果显示乌龟Sox gene的扩增片段与人SRY gene扩增片段大小相同,为220bp左右,且雌雄个体间无差异;最佳扩增条件为:Mg^2 2.0mM、dNTP120μM、引物0.3μM及退火温度52℃。本研究为探索乌龟的性别决定机制以及Sox gene进货的保守性提供分子资料。  相似文献   
8.
9.
Although the effects of constant temperatures on hatchling traits have been extensively studied in reptiles, the effects of fluctuating temperatures remain poorly understood. Eggs of the Chinese three-keeled pond turtle (Chinemys reevesii) were incubated at a constant temperatures (28 °C) and two fluctuating temperatures (28±3 °C and 28±6 °C) to test for the influence of thermal environment on incubation duration, hatchling traits, and post-hatching growth. Incubation duration was shorter at constant temperature than at fluctuating temperatures. The sex ratio of hatchlings varied among temperature treatments, with more females from 28±6 °C than from 28 °C. The size and mass were greater for hatchlings from a constant temperature than from fluctuating ones, but this difference in body size disappeared when the hatchlings were 3 months old. In addition, the swimming ability, survival, and growth of hatchlings from fluctuating temperatures did not differ from those of hatchlings from constant temperature, when they were kept at an artificial environment without food scarcity or predation. Therefore, the thermal environments with various temperature fluctuations used in this study do not significantly affect fitness-related hatchling traits in this species.  相似文献   
10.
2000年至2002年冬季,在河南董寨国家级自然保护区对我国特有珍稀雉类白冠长尾雉(Syrmaticus reevesii)越冬期栖息地进行了调查,并结合RS和GIS在多个尺度上对其栖息地选择进行了分析.结果表明,不同尺度上影响白冠长尾雉越冬期栖息地选择的因素存在差异,影响因子之间还存在相互作用.在微生境上,影响因子主要是坡度、乔木盖度以及坡向余弦值与灌木高度的相互作用;在115 m尺度上,关键因子是灌木林、阔叶林和针叶林的面积;250m尺度上,主要因子是针叶林和阔叶林的面积及针叶林与阔叶林面积的相互作用;对于距离因素,到河漫滩和到农田的距离是影响白冠长尾雉越冬期栖息地选择的关键因子.根据回归分析和AIC及AICc值,115 m尺度上栖息地变量对白冠长尾雉越冬期的栖息地选择影响最大.综合分析发现,在较大的尺度上,影响白冠长尾雉越冬期栖息地选择的关键因子有针叶林面积、阔叶林面积、针叶林和灌丛面积的相互作用、到河漫滩的距离以及到农田的距离.  相似文献   
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