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大兴安岭林区雪兔冬季营养状况的初步评价   总被引:1,自引:0,他引:1  
通过对大兴安岭林区雪兔肾脏重量和肾脏中心脂肪指数的研究,初步评价了不同年龄性别组雪兔以及冬季不同月份雪兔体况的差异。雪兔左肾重量大于右肾,不同年龄性别组雪兔间肾重存在极显著的差异(P<0.01),肾重与体重呈显著的正相关性(P<0.01);雪兔肾重和KFI值存在月份间差异,KFI值在不同的年龄性别组间也呈现明显的差异性(P<0.01)。  相似文献   
3.
Background: Hematology and serum biochemistry values can be useful for evaluating the health of populations of captive and free-living European brown hares ( Lepus europaeus ). However, current information is fragmented and incomplete.
Objective: The objective of this study was to determine normal hematology and serum chemistry values for a population of captive European brown hares and to investigate differences related to sex and age.
Methods: Routine hematology and serum chemistry values were determined for 48 captive European brown hares in Catalonia (northeastern Spain): 21 young (6 males and 15 females) and 27 adult (14 males and 13 females) hares. Blood was obtained by auricular venipuncture while animals were physically restrained. Results were expressed as the mean ± SD, and reference intervals were calculated as the mean ± 2SD.
Results: RBC count, PCV, concentrations of hemoglobin, total protein, albumin, gamma globulin, urea nitrogen, and creatinine, and alanine aminotransferase activity were significantly higher in adults than in young hares, and alkaline phosphatase activity and total bilirubin concentration were lower. Sex differences were not observed.
Conclusions: Hematology and serum chemistry results obtained in this study are considered representative for healthy captive European brown hares. A single reference interval can be used for values from male and female hares, however, age-specific intervals are needed for some analytes.  相似文献   
4.
现代家兔起源于野生穴兔,它与山兔属的野生兔是同科而不同属的动物,学术界对家兔的起源地有外来论和原产论两种不同的观点。1400~1800年前我国家兔驯化首先从宫廷开始,然后传到民间,并由北向南逐步扩大,但真正形成生产性动物只有200余年的历史。  相似文献   
5.
Simulation studies have indicated that a valuable increase in mean annual yield could be achieved in the South African anchovy, Engraulis capensis , fishery if below-average recruitment could be forecast at the start of the fishing season, 6 months before recruitment can he reliably measured. This paper reports on initial investigations into biological and environmental indicator- which could be used to make such forecasts. Valid estimates of recruitment strength in the species are available from 1985 to 1992 and the environmental and biological indicators of interest have been monitored for periods starting from between 1984 and 1988, to the present. Most of the data were obtained from monitoring on anchovy spawner biomass surveys which have been undertaken each November since 1984.
A conceptual model of the factors influencing the recruitment process was constructed and the available data were examined for empirical evidence of the importance of each event included in the model. Fluctuations in copepod biomass and production on the spawning grounds, the incidence of oocyte atresia in adult females, the incidence of southerly winds at Cape Point and the distance offshore of the 16°C isotherm at Cape Columbine were associated with fluctuations in anchovy recruitment. It is suggested that particular attention should be paid to monitoring of these variables to investigate further these associations. If persistent relationships are found, it may be possible to construct an expert system to forecast recruitment from observed values of these variables at the start of a fishing season. A preliminary set of three decision rules is presented.  相似文献   
6.
In common with other farmland species, hares (Lepus spp.) are in widespread decline in agricultural landscapes due to agricultural intensification and habitat loss. We examined the importance of habitat heterogeneity to the Irish hare (Lepus timidus hibernicus) in a pastoral landscape. We used radio-tracking during nocturnal active and diurnal inactive periods throughout one year. In autumn, winter and spring, hares occupied a heterogeneous combination of improved grassland, providing food, and Juncus-dominated rough pasture, providing refuge. In summer, hares significantly increased their use of improved grassland. This homogeneous habitat can fulfil the discrete and varied resource requirements of hares for feeding and shelter at certain times of year. However, improved grassland may be a risky habitat for hares as silage harvesting occurs during their peak birthing period of late spring and early summer. We therefore posit the existence of a putative ecological trap inherent to a homogeneous habitat of perceived high value that satisfies the hares’ habitat requirements but which presents risks at a critical time of year. To test this hypothesis in relation to hare populations, work is required to provide data on differential leveret mortality between habitat types.  相似文献   
7.
贝珠潮  赵岷阳 《草业科学》1993,10(2):45-47,52
本文通过用沙棘、白榆、刺槐叶粉加工成的颗粒饲料进行的喂兔试验,探讨了这三种树叶作为林业饲料的开发价值。  相似文献   
8.
The study aimed to explore the phylogeny and genetic diversity of 3 hare species in Xinjiang by molecular genetics methods, define the relationship and taxonomy status, assess diversity level of Lepus in Xinjiang, and provide the basic data for conservation genetics of hares in Xinjiang and even in China. Three mitochondrial DNA genes, COI, ND4 and 16S rRNA, were used as molecular markers, and the sequences of 3 genes of 57 samples collected from 8 different regions (4 geographic groups) in Xinjiang were determined by PCR amplification and sequencing technology. After the sequences of COI, ND4 and 16S rRNA of each sample were revised and pooled together, data were analyzed with softwares such as MEGA 7, DNAsp 6, Arlequin 3.1 and MrBayes 3.2. A total of 43 haplotypes were detected from the combined sequences of 3 genes of 57 hare samples. Five distinct clades (A-E) and 3 clusters were clearly showed in phylogenetic tree and median-joining network (MJN). Furthermore, the genetic distance between 3 clusters reached the level of species (4.21%-9.09%). However, the genetic distance between hares from northern Xinjiang (Clade E) and those from central Xinjiang (Clade D) were not up to the level of species (≤2.26%) in the third cluster. The haplotype diversity (h) of Lepus yarkandensis, Lepus tibetanus pamirensis and Lepus tolai lehmanni were higher(0.979±0.014, 0.972±0.064 and 0.972±0.064, respectively), while the nucleotide diversity (π) of the L. t. lehmanni and L. t. centrasiaticus were higher (0.033±0.018 and 0.023±0.015, respectively). Based on comprehensive analysis of 3 genes of mitochondrion and reference with published research, it is suggested that hares from southwestern Pamir Plateau of Xinjiang should belong to L. t. pamirensis. Meanwhile,hares distributed in northern and central Xinjiang might be considered as L. t. lehmanni and L. t. centrasiaticus. Moreover, there is abundant genetic diversity in the 3 hare species in Xinjiang, and the obvious phylogeographic pattern is showed.  相似文献   
9.
10.
Abstract

Plant growth is frequently limited by Fe‐related chlorosis on calcareous soils and by mineral toxicities on strongly acid soils and mine spoils. Better adapted varieties are needed for both soil situations, which are not always economically correctable. In a search for such geraplasm, 4 species (20 accessions) of Eragrostis were grown in greenhouse pots of a calcareous soil at pH 7.3. Two species were also compared on acid mine spoil at pH 3.5 and 4.7.

Species, and accessions within species, differed significantly in tolerance to the calcareous soil, as measured by susceptibility to chlorosis and yield of plant tops. The range in top yield was 11‐fold for accessions of Eragrostis capensis, 3‐fold for Eragrostis lehmanniana, and 1.7‐fold for Eragrostis superba. Eragrostis plana (P.I. 364340) was more tolerant to acid mine spoil (pH 3.5) but less tolerant to calcareous soil (pH 7.3) than Eragrostis superba (P.I. 364833).

Chlorosis and poor growth of certain accessions on calcareous soil (pH 7.3) were not explained by specific mineral deficiencies or toxicities. However, the tops of chlorosis‐susceptible accessions had lower ratios of Fe/Mn, Fe/Zn, and Fe/Cu than those of chlorosis‐resistant accessions. This imbalance is believed to interfere with Fe metabolism in plant tops.

Results suggested that superior strains of Eragrostis species can be selected for adaptation to calcareous or acid soils and that certain accessions characterized in these studies can be useful in studying the physiological mechanisms of mineral stress resistance in plants.  相似文献   
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