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本试验对1头黄占鹿的耳缘皮肤组织采用0.1%胶原酶(Ⅰ型)消化组织块法进行原代培养,反复传代纯化,获得了成纤维细胞,进行了生物学特性观察,并对各代细胞进行了常规冷冻保存。利用Photoshop软件对F12代细胞染色体进行了核型分析,结果表明该黄占鹿的染色体数目为68,常染色体中1号和7号为M染色体,其余的均为A常染色体;X染色体是最大的A染色体,Y染色体是最小的M染色体;该黄占鹿的核型式为4(M)+62(A),XY(A,M);对部分冷冻细胞进行了解冻培养,解冻存活率和贴壁率分别为61.04%、38.85%。  相似文献   
2.
本文报告对我国5种假霜霉的研究结果,其中荨麻假霜霉(Pseudoperonosporaurticae)是在中国的首次记录。标本保存于四川雅安四川农业大学。  相似文献   
3.
The prevalence of piroplasms in a closed population of fallow deer (Dama dama L.) living in the Italian preserve of “Bosco della Mesola” - Ferrara (Mesola wood) was investigated. Blood samples and ticks were collected from 62 fallow deer. On microscopic observation, 28 (45.0%) blood samples were positive for piroplasms while PCR provided evidence for piroplasms infection in 47 (75.8%) fallow deer. The 67 ticks, collected from positive and negative animals, were identified as Ixodesricinus L., 1758 (89.6%) and Haemaphysalisconcinna Koch, 1844 (10.4%). At the PCR, four samples of I. ricinus were positive for piroplasms. The sequences of the 18S rRNA gene from both blood and ticks were identical and showed high identity (99.6%) with Theileria sp. 3185/02 (DQ866842) and Theileria capreoli (AY726011) from roe deer. Interestingly, the phylogenetical analyses evidenced differences between the Theileria strain from Mesola wood and the ones isolated in fallow deer from other Italian areas.  相似文献   
4.
The aim of the present study was to describe the suckling behavior of the offspring of farmed European fallow deer Dama dama in the postnatal period. Video surveillance footage from the first 18 days postpartum was analyzed in detail to reveal that the duration of interactions between the mother and the offspring changed with the fawns’ age. The duration of mother‐offspring interactions was longest between postpartum days 12 and 18. The frequency of interactions at different times of the day varied in the analyzed periods. The results of the study could be used to increase the welfare of farmed deer.  相似文献   
5.
In southern Sweden, maintaining high cervid densities through supplemental feeding has become a common management practice. We aim at investigating deer browsing pressure on young Norway spruce in relation to distance from supplemental feeding sites. Because available forage is considered important in understanding browsing patterns, we modeled several factors affecting food availability, and their interaction effect with distance. We confirmed earlier studies about a locally high browsing pressure on natural vegetation adjacent to supplemental feeding sites where browsing pressure declined with distance and alternative forage abundance. Novel is that browsing on spruce occurred in 27.6% of the investigated plots. The browsing pressure of those plots averaged 9%. Distance was the most important factor in relation to browsing. The interactive effect of occurring field layer (FL), and deciduous trees was also highlighted as these significantly affected the relationship between browsing pressure on spruce and distance. In the studied conditions, browsing pressure ceased at ca. 205 m, whereas in scenarios of an abundant FL, browsing levels were negligible already at 0 m from supplemental feeding sites. We suspect that most of the browsing was caused by fallow deer in our study area.  相似文献   
6.
To determine the extent to which wild deer are contributing in the transmission of Fasciola hepatica (liver fluke) livers from deer shot by hunters, farmers undertaking population control on their farms and vertebrate pest controllers were collected and frozen. The livers were later thawed, sliced and examined for the presence of adult flukes or evidence of past infection. Livers from 19 deer were examined (18 fallow [Dama dama] and one sambar [Rusa unicolor]). Seventeen of the fallow deer were animals collected on farms near Jindabyne, New South Wales. The remaining fallow deer was collected in the Australian Capital Territory and one sambar deer was collected in north-eastern Victoria. Nine of the 17 deer (53%) from the Jindabyne area were either infected with Fasciola hepatica (liver fluke) or had thickened bile ducts indicating past infection. Infection levels in the infected animals varied widely from 3 liver fluke to over 50 per liver. No sign of infection was present in the deer from the Australian Capital Territory or Victoria. Fallow deer are wide-spread in the Jindabyne area and their population is increasing. It is likely their contribution to the maintenance and distribution of F. hepatica to livestock in the Jindabyne area, and in other livestock rearing areas of south-eastern Australia, is important and increasing.  相似文献   
7.
Contents: The quantitative morphology of the seminiferous epithelium was studied in 10 testes of 16- to 17-monthsold fallow bucks (Dama dama). Seminiferous tubules constitute 77.2% of the testicular parenchyma and amount to a total length of 400–750 m per testis. According to varying cell associations 6 different stages can be observed during the spermatogenic cycle. The average tubular diameter varies between 215 μm (stage 1) and 230 μm (stage 8), the epithelial height between 67.6 μm in stage 3 and 71.9 μm in stage 8 when spermiation occurs. From primary spermatocytes during the prophase of the first meiotic division preleptotenes have smallest nuclear (203.7 μm3) and cellular (469.1 μm3) volumes, whereas late diplotenes show a nuclear volume of 846.7μm3 and a cellular volume of 3440.5 μm3, that is an increase of more than 4 times for the nucleus and more than 7 times for the cell body. Numerical analysis reveals 4 spermatogonial divisions and a considerable loss of spermatogenic cells during the second meiotic division and subsequent spermiogenesis. Sertoli cells constitute between 31.4% (stage 4) and 38.3% (stage 1) of the tubular epithelium. The calculated cell volume of an individual Sertoli cell increases during every cycle from 6515.3 μm3 instage 3 to 8350.0 μm3 in stage 8; that is a volume change of 22%. The Sertoli cell organelle with most prominent cyclical variations is the endoplasmic reticulum. A lipid cycle is absent in the seminiferous epithelium of the fallow deer. Inhalt: Quantitative Studien am Keimepithel des männlichen Damwilds (Dama dama). Das Keimepithel im Hoden von fünf 16 bis 17 Monate alten Damwildjährlingen (Dama dama) wurde mit morphometrischen Methoden untersucht. Tubuli seminiferi machen 77,2% des Hodenparenchyms aus; die Gesamttubuluslange pro Hoden betragt zwischen 400 und 750 m. Sechs Spermatogenesestadien können beim Damhirsch identifiziert werden, wobei für diese Einteilung wechselnde Zellassoziationen im Keimepithel zugrunde gelegt wurden. Der Durchmesser der Tubuli seminiferi wechselt zwischen 215 μm (Phase 1)und 230 μm (Phase 8). Die Tubulusepithelhöhe schwankt ebergfalls zwischen 67,6 μm in Phase 3 und 71,9 μm in Phase 8 (Spermiation). Präleptotäne habendie kleinsten Kern- und Zellvolumina (203,7 μm3 bzw. 469,1 μm3) von allen Spermatozyten I. Ordnung, Diplotäne aus Phase 4 die größten Werte (846,7 μm3 bzw. 3440,5 μm3), das ist ein Zuwachs um das Vierfache bei mKern und um das Siebenfache beim Zeilleib. Eine numerische Anaiyse derZellzahlen in Tubulusquerschnitten aus den verschiedenen Phasen der Spermatogenese erlaubt die Schlußfolgerung, daß es 4 Spermatogonienteilungen bei dieser Spezies gibt, und daß eine beträchtliche Anzahl aller rechnerisch möglichen Keimzellen während der Spermatokenese verloren geht, vor allem während der zweiten Reifeteilung und der Spermiogenese. Sertolizellen machen zwischen 31,4 (Phase 4) und 38,3% (Phase 1) des Keimepithels aus. Eine Sertolizelle aus Phase 3 besitzt ein rechnerisches Zellvolumen von 6515,3 μm3, eine Zelle aus Phase 8 ein Zellvolumen von 8350,0 μm3. Somit verringert und vergrößert sich das Volumen der einzelnen Sertolizelle um ca. 22% in jedem Keimepithelzyklus. Das endoplasmatische Retikulum der Sertolizelle ist das Organell mit den auffälligsten zyklischen Veränderungen. Der Lipidgehalt des Keimepithels ist minimal; ein Lipidzyklus im Keimepithel, wie für andere Spezies beschrieben, existiert beim Damwild nicht.  相似文献   
8.
There is a growing interest on the potential interplay between weather, habitat, and interspecific competition on population dynamics of wild herbivores. Favorable environmental conditions may buffer the negative effects of competition; conversely, competition may be expected to be stronger under harsh environmental conditions. We investigated relationships between competitor abundance, weather, and habitat cover on density and local distribution of a medium-sized herbivore, the roe deer Capreolus capreolus, as well as its spatial overlap with fallow deer Dama dama in a Mediterranean protected area. Over 11 years (2007–2017), roe deer density was not affected by spring–summer rainfall in the previous year and decreased with increasing density of fallow deer in the previous year. Hence, over the considered temporal scale, results supported a major role of competition over weather in influencing population trends of roe deer. At a finer spatial scale, roe deer occupancy was negatively affected by local abundance of fallow deer, especially in “poorer” habitats. We found a slight support for a positive effect of fallow deer density on interspecific spatial overlap. Moreover, fine-scale spatial overlap between deer species increased with decreasing rainfall in spring–summer. Fallow deer were introduced to our study area in historical times and their role as superior competitors over roe deer has been found also in other study areas. We suggest a potential role of harsh weather conditions during the growing season of vegetation (i.e. scarce rainfall) in triggering the potential for ecological overlap, emphasizing the negative effects of interspecific competition.  相似文献   
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