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Clinical examination and emergency care in newborn puppies is difficult, due to their different physiological characteristics and needs from those of adult dogs. This paper reviews the physiological events during parturition and the influence of parturition on puppy health.

An adjustable three-point hitch dynamometer with a draft capacity of 50 kN was developed to measure forces on the tractor and mounted implements. The design concept of the dynamometer was based on two linkage frames mounted between tractor links and the implement. The force sensing elements were comprised of a loadcell that was installed between the frames. The system provides variable width and height of the dynamometer links to satisfy a wide range of implement dimensions. All mounted tillage implements at categories II and III such as plows, cultivators and harrows were able to be tested by this dynamometer excluding mounted implements powered by power take-off (PTO). The dynamometer was calibrated and several field tests were conducted to measure the force required to pull a moldboard plow in a clay loam soil. The calibration showed a high degree of linearity between the draft requirements and the dynamometer outputs. Field tests showed that it was able to function effectively as intended without any mechanical problems.

Sorghum anthracnose is a disease of worldwide importance and host-plant resistance is the most practical method of disease management. In this study, 154 sorghum accessions from the Botswana collection maintained by the United States National Plant Germplasm System were inoculated with Colletotrichum sublineolum and evaluated for disease resistance at the Tropical Agriculture Research Station in Isabela, Puerto Rico during 2007 and 2008. A resistant response was observed for 69 accessions in 2007 and for 48 accessions in 2008 with no acervuli development observed on inoculated leaves. The low frequency of resistant germplasm is expected from a region of low annual rainfall. However, disease severity was low for the susceptible accessions with a mean severity of 11% for the 85 susceptible accessions observed in 2007 and 17% for the 106 susceptible accessions identified in 2008. The highest frequency of resistant accessions was observed for the Ngamiland district with 58% of the accessions rated as resistant, whereas the frequency of resistant accessions ranged from 22% to 36% for the other districts. The lowest mean disease severity was also observed for the susceptible accessions from the Ngamiland district with the highest mean disease severity observed for susceptible accessions from the Kgatleng district. The resistant accessions identified in this study would be useful for the development of disease resistant varieties and the results indicated an ecogeographic association with disease resistance.

Wild Triticum and Aegilops species are increasingly used in wheat breeding programmes around the world as donors of genes conferring resistance to biotic and abiotic stresses, as well as of genes that contribute to the improvement of grain quality. In the present study, thirty-nine accessions of diploid species with the A genome (Triticum boeoticum and T. urartu) were evaluated for the presence of the genes conferring resistance to powdery mildew (Blumeria graminis) and leaf rust (Puccinia recondita) using both inoculation tests and sequence tagged sites (STS) marker analyses in order to find correspondence between STS markers and resistance as a trait. The most resistant entries were T. boeoticum accessions. All the marked Lr and Pm resistance genes (Pm1, Pm2, Pm3, Lr10, Lr47, Lr25 and Lr28) were identified in the check T. aestivum cultivar Bezostaya 1. The resistance to powdery mildew in the material studied was conferred by the combination of the Pm1 gene with either Pm2 or Pm3. The Pm1 and Pm3 markers appeared to be suitable for tracking these powdery mildew resistance genes, while the Pm2 gene marker cannot be considered as usable in various genetically different wheat accessions. The presence of the genes Lr25, Lr28 and Lr47 seems to be particularly useful for obtaining leaf rust resistance in T. boeoticum and T. urartu species.

The paper compares the quality of Festulolium, Dactylis glomerata and Arrhenatherum elatius at the end of the growing season over three years with the contrasting weather in the Czech Republic. The effect of pre-utilisation dates in June or July on the quality of grass forage in October, November and December (harvest dates) was investigated. In the first two years, Arrhenatherum elatius exhibited higher yields (P < 0.05) than Festulolium and Dactylis glomerata. In all treatments, differences between the species and between the years were inconsistent for organic matter digestibility (OMD) and neutral detergent fibre (NDF) but Festulolium showed the lowest crude protein (CP) in all years and crude fibre (CF) in the first 2 years. The longer re-growth time due to earlier final cut in summer increased the yield and decreased the nutritive value in winter. Yields of DM, OMD and CP content generally declined and the CF content increased with the delay of winter harvest. Significant species harvest date interactions in some years were due to the steep increase of CF and NDF in Festulolium. Based on DM yields and nutritive value, all species have some merits as forage for use in possibly extended grazing season. Festulolium and Dactylis glomerata could be used to extend the grazing period in continental conditions. Arrhenatherum elatius had sufficient quality at both dry and warm end of the growing season due to the fact that Arrhenatherum elatius was a representative of drought-resistant species; however, intense grazing could suppress it.

In arid and semiarid regions of northern China, there is an increasing interest in using water-saving superabsorbent polymer (SAP) for field crop production. Experiments were conducted during 2009 and 2010 to study the growth and yield characteristics of summer corn (Zea mays L.) under different (control, 0; low, 10; medium, 20; high, 30 and very high, 40 kg/ha) rates of SAP in a drought-affected field of northern China. Corn yield increased slightly following SAP application at low and medium rate, but significantly at high and very high rates by 22.4 and 27.8%. At the same time, plant height, stem diameter, leaf area, biomass accumulation, harvest index and relative water content as well as protein, sugar and starch contents in the grain increased significantly following SAP treatments. The optimum application of superabsorbent polymer for corn cultivation in the study area would be 30 kg/ha as it best increased the grain yield and quality and maintained higher levels of soil nutrients. Lower rates (10 and20 kg/ha) or higher (≥ 40 kg/ha) rates would neither be sufficient nor economical. We suggest that the application of SAP at 30 kg/ha could be an efficient and economic soil management practice for summer corn production in the drought affected regions of northern China or other areas with similar ecologies.

Cholecystokinin (CCK) affects the intestinal motility but in ruminants the question has not been entirely explored. The aim of this study was to examine the precise effects of CCK-octapeptide (CCK-OP)and its amphibian analogue, cerulein, on duodenal motor activity in unfasted rams in the course of chronic experiments. Five rams underwent the implantation of a strain gauge force transducer to the duodenal wall, and - additionally - the bipolar platinum electrodes to the duodenal bulb, distal duodenum, near the strain gauge force transducer, and proximal jejunum. During continuous motor recordings, 0.15M NaCl or CCK peptides were administrated intravenously. Injections of CCK-OP at doses of 20 (over 30 s), 200 (over 30 or 60 s), and 2 000 (over 30, 60, or 120 s) ng/kg of body weight and injections of cerulein at doses of 1, 10, or 100 ng/kg (given over the same periods) were each administered in the course of duodenal phase 1, 2a, or 2b of the migrating motor complex (MMC), i.e. 5 min after the onset of each phase. Injections of the smallest doses of CCK peptides exerted a slight and mostly insignificant effect on the duodenal areas under contraction (AUC). In the duodenum, the moderate doses of the hormones evoked short stimulatory effects followed by longer inhibitory biphasic effects on AUC. These effects were inversely related to the duration of the hormone injection. It is concluded that CCK evokes stimulatory and inhibitory (biphasic) physiological effects on duodenal motility in sheep.

Our study aimed to determine morphometric data for wild boar (Sus scrofa) in various areas of the Czech Republic and the potential influence of environment on its body measurements. Three localities with varying agricultural systems and overall landscape structure were selected. Hunted boars were measured for height at the withers, body length, ear length, metatarsal length and weight (depending on the circumstances, either dressed with head, without head, or undressed). We also determined the age of the hunted boars according to teeth development. During 2003-2007, a total 654 boars were examined in various age categories. Body development was similar in all areas and without statistically significant differences until the age of 6-7 months. From 8 months, statistically significant differences in body proportions occur across all localities. It is just at that time that carrying capacities change in the selected localities. The results show that morphometric differences among boars of the same age are influenced by external environmental conditions in which the boars live.

The contribution presents the modelling solution of the potential scenarios impact of the Common Agricultural Policy of the European Union after 2013 in the selected sectors of the Slovak Republic national economy. The solution is accomplished using the Computable General Equilibrium model with the emphasis on the productive and less favourable agricultural areas and the theoretical rents for agricultural land. If we take into consideration both pillars of the Common Agricultural Policy of the European Union, according to the modelling calculations in Slovak conditions the most favoured is the Conservative scenario, the Reference and the Flat Rate scenario are neutral and the least favourable is the Liberalisation scenario.

Virulences to powdery mildew resistances in barley cultivars mostly carrying unknown resistances were determined in 2009 and 2010. Random spore samples of the airborne pathogen populations originating from winter and spring barley fields were obtained by means of a mobile version of a jet spore sampler by travelling across theCzech Republic. In total 301 isolates were studied, 55 differentials carrying mostly unknown resistances were used and 80 pathotypes were found, of which 26 representing 73.1% of isolates were detected in both years. Virulence frequencies showed a wide range from 0% to 100%. Complexity of the 2010 population slightly increased, mostly due to increasing frequencies of virulence to new resistances, whereas the complexity of virulences to resistances in most other differentials decreased. Pathotype 00027 was the most abundant (10.0%). Diversity of the 2010 population considerably increased due to changes in virulence frequencies.

The experiment was carried out to observe the influence of the CULTAN method (controlled uptake long term ammonium nutrition) on grain yield and yield formation of spring barley cultivar Jersey. In four-year small-plot experiment under conditions of the Czech Republic, two methods of nitrogen fertilization were used: conventional surface fertilization and local fertilizer injection rich in ammonium into soil during vegetation at BBCH 29-30 stages. Furthermore, the impact of sulphur amendment in fertilizer and increased dose of fertilizer were observed. Basic dose of nitrogen was 80 kg N/ha, increased dose 130 kg N/ha. At CULTAN treatment, same or significantly higher grain yields were obtained compared to conventional nitrogen fertilization. Grain yield at CULTAN fertilization is formed mainly on the main stem because of reduced tillering; it has the impact on significantly higher percentage of grain retained on 2.5 mm sieve. A tendency to lower protein content in grain was recorded at local injection of fertilizer compared to conventional fertilization. CULTAN-treated plants showed a lesser dependency of qualitative parameters on fertilizer dose and sulphur amendment in fertilizer. A positive influence of the CULTAN method on yield and quality of grain was observed mainly at the less fertile site.

As far as honey is concerned, microwave oven heating finds its use especially for crystallised honey reliquefying. We focused on monitoring the changes in hydroxymethylfurfural content which is an indicator of heat damage done to honey, among others. Microwave honey heating was carried out in four degrees of microwave power levels over seven variously long time periods. In total, 22 analysed honey samples came directly from bee-keepers from the Czech Republic from the 2004 and 2006 harvests. Hydroxymethylfurfural content was determined by HPLC method using a liquid chromatograph Alliance 2695 with a PDA detector 2996. We obtained relatively interesting results: despite the honey having reached relatively high temperature levels (80-90°C) at the highest power levels and the longest time periods, there was no gradual significant increase in hydroxymethylfurfural content which could be expected at conventional heating. On the other hand, hydroxymethylfurfural content varied in the course of heating of the individual samples, which is a very interesting result. A significant role was played also by the botanic origin of the honeys because the course of the changes in hydroxymethylfurfural content due to microwave heating was not the same in all honeys analysed.

Leaf rust caused by Puccinia triticina is the most important disease among the three rusts of wheat in Bangladesh. The disease occurs in all wheat growing areas of the country with varying degrees of severity. Stem rust caused by P. graminis f.sp. tritici was last observed during the mid 1980s, while yellow rust caused by P. striiformis f.sp. tritici occurs occasionally in the north-western region, where a relatively cooler climate prevails during the winter months. None of the rusts has yet reached an epidemic level, but damaging epidemics may occur in future, particularly if a virulent race develops or is introduced. The genes conferring rust resistance in the breeding lines and wheat varieties released in Bangladesh were investigated at CIMMYT-Mexico and DWR-India. The resistance genes Lr1, Lr3, Lr10, Lr13, Lr23 and Lr26, Sr2, Sr5, Sr7b, Sr8b, Sr9b, Sr11 and Sr31; and Yr2KS and Yr9 were found. An adult plant slow rusting resistance gene Lr34 was also identified in some of the breeding lines and varieties based on the presence of clear leaf tip necrosis under field conditions. Considering the possible risk of migration of the devastating Ug99 race of stem rust into the Indo-Pak subcontinent, the Bangladeshi wheat lines and cultivars are being regularly sent to KARI in Kenya for testing their resistance against this race. The resistant lines have been included in multi-location yield trials and multiplied for future use in order to mitigate the threat of Ug99. The resistant lines have also been included in crossing schemes to develop genetic diversity of rust resistance.

We have tested the effect of water, methanol and dichloromethane extracts from the leaves of several species of Impatiens (I. noli-tangere, I. parviflora, I. glandulifera) on germination of seeds Leucosinapis alba and Brassica napus. All of the tested extracts had inhibitory effects to seeds of all studied plants (except the dichloromethane extracts). The highest activity revealed methanol extract and extract from I. glandulifera.

This study aims to reveal and to compare effects of two different systems of nitrogen (N) nutrition (sidedress application or injection application) on toxicity of NH₄⁺ and mixed nutrition. We investigated whether NH₄⁺ or mixed (NH₄NO₃) application causes significant changes in the endogenous levels of cytokinins (CK), whole plant N and their effects on yield of selected plants. Ammonium sulphate or ammonium nitrate were used as N source in the pot experiment. The yield of Festulolium and Trifolium pratense L. above-ground biomass and roots was more substantially enhanced after sidedress application of both ammonium sources in comparison with injection application. Our results confirmed that the accumulation of CKs in plants is in correlation with their N content (R² = 0.66-0.98). Proportions between individual CK forms remained relatively steady and their dynamics exhibited similar trends after N application. Our results indicate that the negative effect of the application of NH₄⁺ on the growth of Festulolium and clover plants could be effectively modulated by the presence of NO₃^-.

Studies of the migratory dynamics of cyathostomin infective larvae (L₃) in different seasons and with two types of irrigation were carried out over 12 months (September 2006 to September 2007) in the subtropical climate of the Baixada Fluminense region of Rio de Janeiro state, Brazil. Four faecal masses weighing 500 g each from naturally infected horses were placed in a Bermuda grass (Cynodon dactylon) pasture in the beginning of each season. Samples of faeces and grass were collected every 15 days until the end of each season. The highest recovery in faeces occured in Autumn (491 910 L₃/kg dried herbage) and in pasture was achieved in Winter (9 963 L₃/kg dried herbage). The lowest number of infective larvae recovered from faeces (55 100 L₃/kg dried herbage) and pastures (2 188 L₃/kg dried herbage) were achieved in Spring. The nonparametric Kruskal-Wallis test showed a significant difference in infective larvae recovery between the seasons. The collection time of the samples did not affect the larva recovery. The results suggest that in the conditions of the region studied, animals maintained in pasture are at permanent risk of infection.

This paper reviews hypertrophic osteopathy and describes one case report. Hypertrophic osteopathy is a rare pathologic disease process and is observed secondary to a mass in the thorax. In response to the presence of a mass(es), nonoedematous soft tissue swellings and a diffuse periosteal new bone formation develop in all four limbs. The result is mild to severe lameness. A twelve-year-old sexually intact female Cocker spaniel had undergone radical mastectomy on both sides in another veterinary hospital about two years before presentation in our hospital with lameness of both hind limbs. Pain and soft tissue swelling on the distal parts of extremities were determined in clinical examinations. Radiographs revealed periosteal new bone formation on all the long bones of all four limbs, pelvis and sternum; additionally, intrathoracic masses were observed. Euthanasia was performed five months later. Macroscopic examinations of the lungs revealed diffuse and exuberant masses with grizzled whitish cross-sectional colour and with necrotic and haemorrhagic foci. The radius-ulna, tibia, metacarpal and metatarsal bones of both limbs were examined and collected after the necropsy examination. Bone specimens were thicker and the outer surfaces seemed to be rough. At the histopathologic examination of the lung tissue, ovoid or round shaped and hyperchromatic nucleated diffuse anaplastic mammary gland epithelial cells were observed. According to these findings, these masses were diagnosed as the metastasis of malignant mixed tumours.

This work is aimed at the evaluation of the operating parameters and emission of two tractors: Hürlimann H-488 DT and Hürlimann XB Max 100. The measurements were done on a test bench in the laboratory of the Agroscope Reckenholz-Tänikon Research Station ART, Ettenhausen, Switzerland during February 2010. The goal of this paper was to evaluate the operating parameters of the two models of tractors by using classical diesel oil and biofuel, as well as to evaluate the emission (greenhouse gases, dangerous exhaust gases and carcinogens), to make statistical analysis of the results and the conclusion about the samples used and the impact on engine parameters, environment and human health. From the results achieved, it is possible to state the following facts. In each way, the emissions of rape seed methylester (RME) and diesel are equivalent. The values of CO and HC and also particles are lower for RME. But NO_x values are lower for diesel oil. It is liquid that the newer engine of Hürlimann XB Max 100 decreases emission of CO, HC and NO_x significantly.

In an Island of the Netherlands, Pine (Pinus nigra) was planted to stabilize the dunes and to protect the arable lands from the blowing sand. This research was conducted to understand the most important environmental factors responsible for a vegetation change in the Pine plantation and effect of this change on the rare orchid population: Goodyera repens and Listera cordata. Vegetation sampling was carried out according to the Braun-Blanquet phytosociologic method within the three sites of this Island. Twinspan analysis confirmed the definition of three site types and redundancy analysis showed a significant difference between the pure Pine stands and the plots with regeneration. The results revealed that the most significant explanatory variables were litter cover, broadleaved tree cover, and shrub cover indicating the vegetation change under the Pine plantation. The abundance of Goodyera repens is strongly associated with the Pine forest and negatively related to broadleaved cover. Listera cordata could apparently cope with vegetation change. Controlling the herbaceous layer in the Pine plantation can promote the orchid population but on the contrary, promoting the natural regeneration of broadleaved species might endanger them.

The paper examines the role of social capital in Czech agricultural sector. It is argued that social capital, just like economic capital, can be employed as a resource for the improvement of economic performance of agricultural enterprises. This hypothesis is tested on a sample of primary data and an analysis of the selected indicators of social capital is presented. These include personal social networks, membership in agricultural associations and access to sources of information. Following the results, it is argued that the presence of informal personal ties displays a stronger relationship to the entrepreneurial success than formal membership in agricultural associations. This outcome suggests a comparatively strong role of social capital in the dynamics of the sector.

The aim of this study was to determine the impact of the length of calf sucking milk from its own mother on calf growth at the age of 3 months and milk yield of mothers. We tested a hypothesis that the nursing of calves by their own mothers increases the body weight of calves and decreases the milk production. 50 Holstein primiparous cows and their calves were divided into three groups according to the sucking length of calves: 7 days (A), 14 days (B) and 21 days (C). All calves suckled mother's colostrum and milk while mothers were milked twice per day. After weaning from mother calves were kept in individual hutches until 56 days of life, and then in group housing pens. In the period from birth to weaning the calves of group A reached the lowest and the calves of group C the highest daily gains (0.35 kg, 0.46 kg, 0.54 kg; P < 0.01). The lowest gain was recorded in animals of group A (0.55 kg) and the highest gain was reached by calves of group C (0.74 kg) for the period from birth to three months of age. For the first 305 days of lactation cows of group A produced insignificantly more milk than group C (7356.5 kg, 6779.2 kg, 6663.9 kg). A significant difference in milk production was recorded only during the first seven months of lactation (5494.5 kg, 5041.9 kg, and 4872.3 kg; P < 0.05). The long stay of calves with their mothers influences the growth of calves positively, but the milk production of mothers may decrease. Therefore, the stay of calves with the dam within 21 days after birth is not recommended for high-yielding dairy cows.

The Lusatian lignite-mining district (Eastern Germany) is characterized by a high share of marginal post-mining areas. At these sites, crop yield is generally low, and hence, conventional land use systems often fail in terms of reliable and efficient crop production. In this paper the attempt is made to evaluate the production of woody biomass for bioenergy in short rotation coppices (SRC) and alley cropping systems (ACS) with black locust (Robinia pseudoacacia L.) and lucerne (Medicago sativa L.) from the aspect of possible ecological and economic benefits compared to the conventional agricultural recultivation practice. The results show that, due to both high establishment and harvesting costs and comparatively low prices of energy wood, land use systems such as SRC or ACS are currently hardly profitable compared to conventional agriculture. However, the cultivation of black locust resulted in a higher humus accumulation and in a lower harvest-related nutrient export than the cultivation of lucerne as a typical recultivation crop in this region. Therefore, it can be concluded that for an improvement of soil fertility woody biomass production is more beneficial than the conventional agricultural recultivation practice.

The problem of international debts is, by its character, one of the most complex problems which the world economy is now facing. It complicates both the global balance of payments and the financial - credit system stability, with pronounced negative impacts on the currency stabilisation. It hinders the development of international economic co-operation and its higher forms - international economic integration. It is one of the reasons that the symmetrical forms of interdependence are pushed off and displaced by the asymmetrical ones. The global debts problem deteriorates, namely during the last time in interaction with the negative manifestations of the global problems (for example, at present very strongly with the environmental problems), the complex international co-operation climate.

In this study, the effects were investigated of salinity, foliar and soil applications of humic substances on the growth and mineral nutrients uptake of Corn (Hagein, Fardy10), and the comparison was carried out of the soil and foliar applications of humic acid treatments at different NaCl levels. Soil organic contents are one of the most important parts that they directly affect the soil fertility and textures with their complex and heterogenous structures although they occupy a minor percentage of the soil weight. Humic acids are an important soil component that can improve nutrient availability and impact on other important chemical, biological, and physical properties of soils. The effects of foliar and soil applications of humic substances on the plant growth and some nutrient elements uptake of Corn (Hagein, Fardy10) grown at various salt concentrations were examined. Sodium chloride was added to the soil to obtain 20 and 60mM saline conditions. Solid humus was applied to the soil one month before planting and liquid humic acids were sprayed on the leaves twice on 20^th and 40^th day after seedling emergence. The application doses of solid humus were 0, 2 and 4 g/kg and those of liquid humic acids were 0, 0.1 and 0.2%. Salinity negatively affected the growth of corn; it also decreased the dry weight and the uptake of nutrient elements except for Na and Mn. Soil application of humus increased the N uptake of corn while foliar application of humic acids increased the uptake of P, K, Mg,Na,Cu and Zn. Although the effect of interaction between salt and soil humus application was found statistically significant, the interaction effect between salt and foliar humic acids treatment was not found significant. Under salt stress, the first doses of both soil and foliar application of humic substances increased the uptake of nutrients.

Eleven microsatellite loci (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA023, ETH3, ETH225, BM1824) were evaluated for their use in paternity testing in the Yugoslav Pied cattle (YU Simmental cattle) population in Serbia. A total of 40 animals were tested. At the 11 tested loci, a total of 91 alleles were detected. The mean number of alleles per locus was 8.273. Polymorphism information content (PIC) values ranged from 0.58 to 0.88 with the mean value of 0.72. The most informative loci were: TGLA53 (14 alleles, PIC = 0.88), TGLA227 (11 alleles, PIC = 0.82), INRA023 (11 alleles, PIC = 0.86), BM2113 (9 alleles, PIC = 0.80). Combined power of discrimination (CPD) for the 11 microsatellite loci was 0.999. The results of the present study confirm that the analysed set of 11 microsatellite markers recommended by ISAG is suitable for paternity testing in Yugoslav Pied cattle in Serbia.

Summerling (six-month old) noble crayfish fed two forms of freshly decapsulated (FD) Artemia cysts more than tripled their weight during a 75-day experiment under controlled conditions. Final survival rates were at the level of 90%. Feeding commercially available industrially decapsulated cysts resulted in both poor growth and reduced survival (22.2%). Therefore FD Artemia cysts may be an effective diet for crayfish culture, but dehydrated industrially decapsulated (DID) cysts should be used with caution to avoid products of low quality. That should be considered especially in slow feeders such as crayfish because of leaching of nutrients from DID cysts. Costs of the processing of freshly decapsulated cysts are discussed.

This experiment was conducted in order to compare the effects of Nigella sativa (NS) and silver sulfadiazine (SSD) cream on healing of burn wounds in rats. Fifty four adult, male Wistar-albino rats were divided into three groups of equal numbers. A burn was generated on the backs of all the rats. The burned areas in the first, second and third groups were covered with daily cold cream (control), SSD cream and NS cream (50% NS oil + 50% cold cream), respectively. Four, nine, and 14 days later, the rats were sacrificed and the burned skin tissue samples were collected for histopathological examinations. Histopatological evaluations on the 4th, 9th and 14th days showed burn healing to be better in the NS and SSD groups with respect to the control group. Wound healing was significantly different among the groups at 4th, 9th and 14th days (P < 0.001). In conclusion, application of NS and SSD cream are effective in healing burn related skin wounds in the rat model.

Climate change is expected to influence the distribution and population dynamics of many insect pests, with potential severe impacts on forests. Spruce bark beetle Ips typographus (L.) (Col.: Curculionidae, Scolytinae) is the most important forest insect pest in Europe whose development is strictly regulated by air temperature. Therefore, climate change is anticipated to induce changes in the pest's distribution and development. We used the PHENIPS model to evaluate climate change impacts on the distribution and voltinism of spruce bark beetle in the Czech Republic. Two future time periods - 2025-2050 (near future) and 2075-2100 (distant future) - are addressed. The period 1961-1990 is used as the reference. We found that while a two-generation regime dominated in the Czech Republic in the reference period, significant three-generation regime regions are projected to appear in the near future. In the distant future, the three-generation regime can be expected to occur over all existing coniferous stands in the Czech Republic. The analysis of altitudinal shift of n-generation regime regions indicates noticeable expansion of Ips typographus development to higher elevations, leading for example to disappearance of one-generation regime regions in the distant future. Uncertainties and limitations of the presented findings are discussed as well.

Information on the historical background of the present forest conditions is needed for proper decisions on forest management. Disturbances play a major role in the formation of forest structure and composition. This paper compares the present break-up of mountain spruce stands in the Bohemian Forest (in the Šumava Protected Landscape Area) with conditions during their initiation using dendrochronological techniques. On three selected localities we established two study plots within relatively old stands of unknown origin. Stands were recently broken up by a windstorm. The present situation was described by diameter and decay class distribution. To describe the situation at the stand initiation, we cored at least 40 stems on each plot to get the age structure and growth series of trees. Disturbances were marked by discovering synchronous releases on tree-ring series. Main population waves were initiated in association with severe disturbances during a relatively short period, leading to the establishment of relatively even-aged, homogeneously looking stands. The disturbances were synchronized between plots and accounted for by historically known windstorms or bark beetle outbreaks; notwithstanding, logging as a disturbance factor is also particularly possible.