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31.
The antigen detection enzyme immunoassay (AgELISA) in conjunction with parasitological examination of blood were used to study the enzootic situation of cameline trypanosomiasis in mid-Eastern Sudan. A one year survey showed that the infection is endemic among pastoral camels with a prevalence of 5.4% based on parasitological examination and 31.3% based on AgELISA. The infection rate was higher during the dry period (November to May) than the wet season. Young camels had a much lower infection rate as detected by parasitological techniques, but not with AgELISA. A lower prevalence of infection was detected by buffy coat technique (BCT) in herds of camels raised by nomads compared with those kept by agropastoralists and in camels located in the southern districts of mid-Eastern Sudan. 相似文献
32.
M. Viso M. R. El Jaraki J. Espinasse A. L. Parodi J. F. Dedieu 《Veterinary research communications》1985,9(1):213-219
The method of lung lavage under fiberoptic control allowed collection of alveolar cells in non-anaesthetized adult cows.The median section of the diaphragmatic lobe was lavaged with five consecutive aliquots of 30 ml each. Every one was analysed separately. A mean of 25.6% of instilled fluid was recovered and this is lower than amounts obtained on isolated lungs or in anaesthetized calves (about 50%).The cellular formula of 30 samples showed 83.5% of macrophages, 6.0% of lymphocytes, 9.4% of polymorphonuclear cells, 0.5% of monocytes. Cellular viability and total cell count were similar to previously published data. All results were found to be independent of the washing sequence. This simple and well tolerated technique appeared to be a useful tool for the study of defence mechanisms of deep lung. 相似文献
33.
Sebaei Mahmoud G. El El-Shafei Reham A. El-Adl Mohamed A. Farag Amany Eladl Abdelfattah H. 《Veterinary research communications》2022,46(2):419-430
Veterinary Research Communications - This study evaluated the diuretic, antioxidant, anti-inflammatory, and immunological effects of a commercial diuretic (CD) (composed of ammonium chloride,... 相似文献
34.
Summary An instrumental method for the measurement of the toxic value of preservatives against mould fungi on wood and wood products was tested as an alternative to the widely used visual method with its inherent disadvantage of subjectivity. The new criterion of effectiveness to be used was light reflectance as measured by either the Zeiss photometer (Leukometer) or the Zeiss spectrophotometer (Spekol 10) fitted with the Rd/0 reflectance adapter. Sodium pentachlorophenate and the WR-3 (quaternary ammonium compound), applied to pine and birch wood samples were tested for effectiveness against five species of fungi capable of causing surface moulding. Although the reflectance method was more laborious, the results obtained seem to be better than those obtained by the visual method. The proposed method appears to be of practical value in eliminating difficulties involved in the subjective assessment of both the intensity of surface growth and the effectiveness of the wood preservatives themselves.Paper sponsored by the State Enterprise of Conservation of Fine Arts Objects, Warszawa ul. Zielna 3The authors thank Dr. J. D. Thornton, CSIRO Division of Forestry and Forest Products, Highett, Australia, for kindly correcting the English text of this paper 相似文献
35.
Summary The process of absorption of water along the tangential direction of the wood is studied by immersing the sample in water. The transport of water is then obtained below the fiber saturation point at the beginning of the absorption and above this fiber saturation point during the process. The potential which drives the transport of the bound-water and free-water through the wood has been considered by testing a diffusional transport model. The transient diffusion with a constant diffusivity has been found to describe not only the process of absorption but also the process of desorption with diffusion of water through the solid and evaporation from the surface. Analytical solutions have been successfully used to describe the stage of absorption during a time of four hours at the end of which an equilibrium of absorption is attained, as well as the following stage of desorption. A model based on a numerical method with finite differences has been found to describe the process of absorption and desorption in various cases, and especially when the equilibrium of absorption has not been attained.This work was carried out with the help and support of the M. R. T. and the French CTB (Wood Technical Center) 相似文献
36.
Zusammenfassung Seit zehn Jahren betreibt der Lel-irstuhl für Waldbau and Forsternrichtung der Universit?t M?nchen intensive Verjüngungsstudien
auf 25 Dauerversuchsfl?chen im Bergmischwald der ostbayerischen Kalkalpen. Am Bei-spiel der Aufnahmedaten yon fünf ausgew?hlten
Versuchsfl?chen werden grundlegende Prinzipien des Ver-jüngungsprozesses im Bergmischwald aufgezeigt and daraus praktische
Konsequznzen abgeleitet.
Alle am Autbau der Altbest?nde des Bergmischwaldes beteiligten Baumarten bilden bislang trotz d utli-cher Waldschadenssvmptome
reichlich Samen von hochwertiger Qualit?t aus.
Damit aus diesem Verjüngungspotential Naturverjüngung entstchen kann, müssen die en tsprechenden überschirmungsverh?ltnisse
lurch den Altbestand gegeben sein. Für die Dichte, Baumartenztusammenset zung and H?henentwicklung der Naturverjüngungspflanzen
ist n?mlich die Uberschirrnung von ganz ent-scheidender Bedeutung. In einem sehr dichten Altbestand, in derv der überschirmungsgrad
fiber 75% liegt , haben Verjüngungspflanzen Schwierigkeiten, sick zu etablieren. Eine Ieichte Auflichtung auf einen über-schirmungsgrad
von 60 (der dann gegeben ist, wenn die rich unter dem Schirm entwickelnde Bodenvege cation Bedeckungsgrade zwischen 20 and
3C einstellt) erm?glicht den Naturverjüngungsflanzen ein überleben. Diese Uberschirmung kann durch einen schwachen Schirmhieb
(Entnahme von etwa einem Vier-tel der Grundtl?che eines geschlossenen Bestandes) erreicht werden. Diese Eingriffsst?rke dürfte
auch unter den Gesichtspunkten der Stabilit?it and des Zuwachsverlustes dill Altbestand zu vertreten sein.
Vor einer st?rkeren Auflichtung des Altbestandes müsses genügend Naturverjüingungspflanztn ant Bo den vorhanden sein. Nur
so is[ gew?hrleistet, daβ these einen Vorsprung vor der Bodenvegatation bekom Men.
Die Pflanzung ist immer dann, wenn sich Schwierrigkeiten mit der Naturverjüngung ergeben, ein geeigne-tes Mittel, um einen
neuen Bergmischwald zu begründen.
Derzeit ist für das Entstehen tines neuen Bergmischwaldes - sei es durch Naturverjüngung odor lurch Pflanzung - Zaunschutz
erforderlich.
Summary In 1976, a research project entitled ’Natural Regeneration of Mixed Mountain Forests ’ was etablished in the Calcareous Alps
of eastern Bavaria, by the Chair of Silviculture and Forest Management of the University Of Munich. Over the past ten years,
the multi-variate aspects of regenaration have bean intensively investigated on 25 permanent research plots. The data from
5 selected plats were extracted and processed. from these data, it will be possible to present some fundamental principles
of natural regenaration processes. From these prin-ciples, it is hoped that some practical applications can be derived.
The mature stands of mixed mountain forests are still able to produce high quantities and good quality of seed, although distinct
symptoms of forest decline are present.
In order to utilize this potential for natural regeneration, an adequate canopy density is necessary. Canopy density is the
crucial factor which regulates the density, species composition and height development of regeneration. In a very heavily,
stocked mature stand with a canopy density of over 75 establishment of regenerations is difficult. When canopy density is
reduced to, for example, 60% (this percentage can be estimated from a ground vegetation covering approximately 20–30 of the
soil), the naturally regenerated, plants have a better opportunity to survive. A 60% canopy density can be achieved by light
shelterwood cutting (removal of approximately 25% of basal area of a closed stand). This type of cutting can maintain the
stability and prevent increment loss of forest stands. It is important that regeneration is established before opening up
the stand, only, then these plants are capable to compete with the other ground vegetation.
Planting is always appropriate when natural regeneration fails.
Fencing is necessary for undisturbed development of natural and artificial regeneration.
Dieses Heft enth?lt waldbauliche Beitr?g zu den Forschungsschwerpunkten Bergwald, Waldschaden und Kiefer. Sie sind überwiegen als Vortr?ge auf der Hochschulwoche der Forstwissenschaftlichen Fakult?t München im Oktober 1987 gehalten worden. Ihre Autoren widmen sie Herrn Professor Dr. Peter Burschel zum 60. Geburtstag.
Auf der Forstlichen Hochschulwoche 1987 in München gehaltener Vortrag. 相似文献
Dieses Heft enth?lt waldbauliche Beitr?g zu den Forschungsschwerpunkten Bergwald, Waldschaden und Kiefer. Sie sind überwiegen als Vortr?ge auf der Hochschulwoche der Forstwissenschaftlichen Fakult?t München im Oktober 1987 gehalten worden. Ihre Autoren widmen sie Herrn Professor Dr. Peter Burschel zum 60. Geburtstag.
Auf der Forstlichen Hochschulwoche 1987 in München gehaltener Vortrag. 相似文献
37.
El Amin Yousif Raddad 《New Forests》2007,34(3):207-222
The genetic variation in seed weight, seed number per kg and seedling traits was compared among eight Acacia senegal provenances originating from the clay plain (east) and sand plains (west) of the gum belt in Sudan. The main objective of
this study was to identify germplasm sources of A. senegal that have a good seed germination capacity and seedling traits suitable for reforestation in the clay-soil part of the dryland
gum belt in the Blue Nile region in Sudan. A specific objective was to tentatively explore the adaptive strategy of A. senegal populations. Seventeen-week-old seedlings were planted in the field at spacing of 3 m × 3 m, giving 100 trees per plot and
replication; within a randomized complete block design with four replications. The experimental site was in the clay plain
region. Seed variables showed significant differences. Clay plain provenances showed considerable variation in seed weight
and seed number. They had the smallest seed weight but the highest seed number, while the sand (western) provenances had the
largest seed weight but lowest seed number. Seedling branch number, root length, root to shoot ratio and shoot dry weight
differed significantly among the provenances 12 weeks after germination. Clay provenances had the highest branch number and
shoot dry weight but the shortest roots and lowest root to shoot ratio. This was interpreted as showing better adaptation
to the site in these local provenances in comparison to those originating from the western sandy soil regions. High positive
correlations were observed between seedling variables, such as root nodule and branch numbers; this could be used for early
selection. The variation was greater between provenance groups than within them, suggesting that especially selection among
groups would yield genetic gain. 相似文献
38.
Effect of Mediterranean saltbush (Atriplex halimus) ensilaging with two developed enzyme cocktails on feed intake,nutrient digestibility and ruminal fermentation in sheep 下载免费PDF全文
Haidy Alsersy Abdelfattah Z. M. Salem Borhami E. Borhami Jaime Olivares Hany M. Gado Maria D. Mariezcurrena Mohamed H. Yacuot Ahmed E. Kholif Mounir El‐Adawy Saul R. Hernandez 《Animal Science Journal》2015,86(1):51-58
The aim of this study was to assess the effects of feeding Atriplex halimus (AH) silage treated with two developed enzyme cocktails to sheep on feed intake, nutrient digestibility and ruminal fermentation. The AH silage was treated without or with 2 L of ZAD1® or ZAD2®/1000 kg with 5% molasses and ensiled for 30 days. Barley grain (300 g/head/day) was fed as an energy supplement once daily at 10.00 hours and AH silage with or without enzyme treatment was offered ad libitum to animals twice daily at 09.00 and 16.00 hours. Sheep were fed on four experimental forage diets comprised of AH silage and barley (D1), AH silage treated with ZAD1® and barley (D2), AH silage treated with ZAD2® and barley (D3) and AH silage treated with a combination of ZAD1® and ZAD2® (1:1) and barley (D4). Ensiling AH with enzymes reduced its contents of neutral detergent fiber and acid detergent fiber. The dry matter intake of AH of D2, D3 and D4 decreased (P < 0.001) as compared to D1. However, enzyme‐treated diets had greater total digestible nutrients intake (P < 0.001) as compared to D1. The nutrients digestibility for D2, D3 and D4 were higher than those for D1 (P < 0.001), and were higher for D3 as compared to both D2 and D4. Sheep fed on D3 had highest (P < 0.001) ruminal total volatile fatty acids concentration, ammonia nitrogen concentration and microbial protein yield. It could be concluded that AH silage treated with ZAD1® or ZAD2® improved digestibility and rumen fermentation in sheep. 相似文献
39.
Elbieta Brzuska 《Aquaculture Research》2004,35(14):1318-1327
The investigation concerned the reproduction effects in carp females of the Hungarian strain 8, Polish strain 2 and French strain F of ovulation stimulation with carp pituitary homogenate (0.3 mg kg?1 and after 12 h 2.7 mg kg?1) or [D‐Tle6, ProNHEt9]GnRH (Lecirelin) with metoclopramide (15 μg kg?1 and 10 mg kg?1 respectively). The ovulation stimulators did not affect the weight of eggs (expressed in g and as the percentage of female body weight). However, in the group treated with pituitary homogenate (I) the least‐square means estimated for these parameters were higher than in the group treated with Lecirelin (II). A statistically significant (P≤0.05) difference in the mean percentage of living embryos after 48‐h incubation was observed between groups I and II, with the eggs obtained from females of group I being of better quality. The origin of females significantly (P≤0.05) affected the weight of eggs. The weight of eggs from females of Hungarian strain 8 was higher (P≤0.05) than the weight of eggs of the other two lines. With respect to parameters for egg quality (percentage of fertilized eggs and percentage of living embryos after 24‐, 36‐ and 48‐h incubation), no effect of the origin of females was observed. The interaction between the spawning agent and the origin of the females was not statistically significant with respect to the two parameters for the weight of the eggs. The least‐square means test for the investigated interaction showed that after the application of pituitary homogenate, the weight of eggs obtained from strains 8 and F was similar (respectively 711.2 g and 665.0 g). However, after the application of Lecirelin the females of strain 8 yielded eggs of a high weight (934.3 g) and those of strain F of a very low weight (373.2 g). A statistically significant (P≤0.05) interaction between ovulation stimulator and origin of females was recorded for the percentage of living embryos after 24‐ and 36‐h incubation. A dependence was found between the latency time and the reproduction effects. 相似文献
40.
Cryptosporidium in farm rabbits is not often recognised due to a low prevalence and asymptomatic course of infection. Nonetheless, incidences of fatal diarrhoeic diseases are frequently noticed in the rabbitries. In this article, we report an outbreak where there was massive mortality among farm rabbits associated with Cryptosporidium infection. The disease was characterised by profuse diarrhoea resulting in the death of rabbits. A pooled faecal sample was screened for a presence of parasites using microscopy methods. In the tested sample no other parasites other than Cryptosporidium oocysts were found. Further identification of the parasite species was performed at a molecular level, using the 18 SSU rRNA, COWP and LIB13 PCR followed by a subtyping at the GP60 gene locus. Sequence analysis of GP60 gene fragment revealed the presence of a novel subtype VbA24 of Cryptosporidium cuniculus. In this outbreak a Cryptosporidium protozoan parasite played a major role in the etiology of the gastrointestinal disorders in rabbits resulting in massive mortality of the infected animals. 相似文献