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951.
952.
Ribavirin (RBV) is a synthetic guanosine analog that is used as a drug against various viral diseases in humans. The in vitro antiviral effects of ribavirin against porcine viruses were demonstrated in several studies. The purposes of this study were to evaluate the adverse effects and pharmacokinetics of ribavirin following its intramuscular (IM) injection in pigs. Ribavirin was formulated as a double‐oil emulsion (RBV‐DOE) and gel (RBV‐Gel), which were injected into the pigs as single‐dose IM injections. After injection of RBV, all of the pigs were monitored. The collected serum and whole blood samples were analyzed by liquid chromatography–tandem mass spectrometry and complete blood count analysis, respectively. All of the ribavirin‐treated pigs showed significant decreases in body weight compared to the control groups. Severe clinical signs including dyspnea, anorexia, weakness, and depression were present in ribavirin‐treated pigs until 5 days postinjection (dpi). The ribavirin‐treated groups showed significant decrease in the number of red blood cells and hemoglobin concentration until 8 dpi. The mean half‐life of the RBV‐DOE and RBV‐Gel was 27.949 ± 2.783 h and 37.374 ± 3.502 h, respectively. The mean peak serum concentration (Cmax) and area under the serum concentration–time curve from time zero to infinity (AUCinf) of RBV‐DOE were 8340.000 ± 2562.577 ng/mL and 16 0095.430 ± 61 253.400 h·ng/mL, respectively. The Cmax and AUCinf of RBV‐Gel were 15 300.000 ± 3764.306 ng/mL and 207526.260 ± 63656.390 h·ng/mL, respectively. The results of this study provided the index of side effect and pharmacokinetics of ribavirin in pigs, which should be considered before clinical application.  相似文献   
953.
In recent decades, wild boars (Sus scrofa) have increased in numbers and distribution in Europe. Compared to other wild ungulates of similar body size, wild boars have a high reproductive capacity. To increase the knowledge of wild boar reproduction, the objective of this study was to investigate characteristics of reproductive organs, and to provide information on the occurrence of abnormalities in reproductive organs from free‐ranging female wild boars. Between December 2011 and December 2015, reproductive organs from female wild boars (>30 kg body weight), were collected during hunting in four Swedish counties at estates where supplementary feeding was applied. The organs were macroscopically examined and measured. The stage of the reproductive cycle was defined according to the ovarian structures and in relation to uterus characteristics. Observed abnormalities were noted. The results from 569 animals that met the requirements to be included in this study showed significant differences in weight and length of the uterus between the various reproductive stages. Sampling region had significant effect on these differences. Abnormalities in the reproductive organs were present in approximately 10% of the examined animals. The prevalence of abnormalities increased significantly with age and was significantly affected by sampling region.  相似文献   
954.
The dynamics of red deer Cervus elaphus populations has been investigated across different environmental conditions, with the notable exception of the European Alps. Although the population dynamics of mountain‐dwelling ungulates is typically influenced by the interaction between winter severity and density, the increase of temperatures and the reduction of snowpack occurring on the Alps since the 1980s may be expected to alter this pattern, especially in populations dwelling at medium ‐ low elevations. Taking advantage of a 29‐year time series of spring count data, we explored the role of weather stochasticity and density dependence on growth rate and vital rates (mortality and weaning success), and the density‐dependent variation in body mass in a red deer population of the Italian Alps. The interaction between increasing values of density and snow depth exerted negative and positive effects on growth and mortality rates, respectively, while weaning success was negatively affected by increasing values of density, female‐biased sex ratio and snow depth. Body mass of males and females of different age classes declined as population size increased. Our data support the role of winter severity and density dependence as key components of red deer population dynamics, and provide insight into the species' ecology on the European Alps. Despite the recent decline of snowpack on the Alpine Region, the negative impacts of winter severity and population abundance on growth rrate (possibly mediated by the density‐dependent decline in body mass) confirms the importance of overwinter mortality in affecting the population dynamics of Alpine‐dwelling red deer.  相似文献   
955.

Purpose

The aim of the study was to present variability of content and quality of soil organic matter on the landslide surface. Attempts were made to demonstrate the progress of the process of soil cover restoration 7 years after the landslides and biochemical activity of soil associated with the restoration of soil cover.

Materials and methods

The landslide area was located in southern Poland, in the Sucha Forest District. The soil properties were studied on a regular grid of points, which covered the entire area of the landslide. In soil samples, particle size, soil aggregates content, pH, total carbon and nitrogen content, microbial biomass carbon and nitrogen and the activity of dehydrogenases were determined. Additionally, the fractions of soil organic matter were used in the study as an indicator of soil quality due to the many important interactions of these components in the soil system.

Results and discussion

This study identified the landslide area as characterised by a stronger diversification of physical, chemical, and biological properties. The upper part of the landslide (in the area referred to as the landslide niche) is strongly eroded and characterised by the least advanced soil cover recovery. Additionally, low soil organic matter content was observed in the upper part of the landslide, which restricted biological activity of the studied soils. Soil microbial biomass carbon increased with restoration of landslide soils.

Conclusions

The soil organic matter plays a key role for the initial stage of soil formation on a landslide. The amount of soil organic matter on the studied landslide had a positive effect on the microbial biomasses C and N, dehydrogenases activity. Estimating the soil organic matter fraction can be utilised as an indicator of changes in soil.
  相似文献   
956.
Superabsorbent polymers of carboxymethyl cellulose-graft-itaconic acid were synthesized using potassium persulfate as a free radical initiator in the presence of N,N′-methylene bisacrylamide as a crosslinker using solution polymerization technique. The structures of the grafted copolymers were characterized by FT-IR spectroscopy and thermogravimetric analysis. The effect of reaction variables such as concentration of carboxymethyl cellulose, itaconic acid, initiator, crosslinker, and neutralizing agent were optimized to achieve a hydrogel with high swelling capacity of 74 g/g (DI water) and 18 g/g (0.9 wt% NaCl solution). The swelling kinetics of the prepared SAP were analyzed by applying the Fickian diffusion model and the Schott’s pseudo second order kinetics model. The diffusion exponents in the Fickian model, n, showed values of 0.73-0.93, indicating that chain relaxation behavior during absorption had a large effect on total absorbency.  相似文献   
957.
The loss of sperm quality in sterlet (Acipenser ruthenus) due to freeze-thaw process in cryopreservation was investigated in the present study. Two antifreeze proteins (AFPI or AFPIII) were used at different concentrations of 0.1, 1, 10, and 100 μg/mL. We compared motility, curvilinear velocity, and plasma membrane integrity of fresh, cryopreserved sperm, and sperm cryopreserved in the presence of antifreeze proteins. Fresh sperm (control) had 85?±?4% motility and 160?±?2 μm/s curvilinear velocity, respectively. After cryopreservation, the motility of frozen-thawed sperm without addition of antifreeze proteins significantly decreased (44?±?9%), compared to the control. The highest motility of frozen-thawed sperm was obtained in cryopreserved sperm with addition of 1 μg/mL of AFPIII (58?±?14%). No significant differences were observed in curvilinear velocity between fresh sperm and cryopreserved sperm with/without addition of AFPI or AFPIII. The flow cytometry analysis revealed that fresh sperm contained 94.5?±?6% live cells, while the cryopreserved sperm only contained 26.6?±?14% live cells. Supplementation of antifreeze proteins has significantly improved the percentage of live cells in frozen-thawed sperm, except 0.1 μg/ml of AFPI group. No significant difference in percentage of live cells was detected in the sperm cryopreserved with 10 μg/mL of AFPI or AFPIII, compared to fresh sperm. Thus, addition of antifreeze proteins to cryopreservation medium could be considered to improve the post-thawed sperm quality of sterlet.  相似文献   
958.
Terrestrial ecosystems represent a major sink for atmospheric carbon (C) and temperate forests play an important role in global C cycling, contributing to lower atmospheric carbon dioxide (CO2) concentration through photosynthesis. The Intergovernmental Panel of Climate Change highlights that the forestry sector has great potential to decrease atmospheric CO2 concentration compared to other sectoral mitigation activities. The aim of this study was to evaluate CO2 sequestration (CO2S) capability of Fagus sylvatica (beech) growing in the Orfento Valley within Majella National Park (Abruzzo, Italy). We compared F. sylvatica areas subjected to thinning (one high-forest and one coppice) and no-management areas (two high-forests and two coppices). The results show a mean CO2S of 44.3 ± 2.6 Mg CO2 ha?1 a?1, corresponding to 12.1 ± 0.7 Mg C ha?1 a?1 the no-managed areas having a 28% higher value than the managed areas. The results highlight that thinning that allows seed regeneration can support traditional management practices such as civic use in some areas while no management should be carried out in the reserve in order to give priority to the objective of conservation and naturalistic improvement of the forest heritage.  相似文献   
959.
Grapevine moths are severe pest insects in European viticulture. Oviposition by grapevine moths is largely influenced by several physical and chemical cues located on the surface of their host plant’s fruits. The contribution of waxy bloom layer on the berry surface for oviposition decision of two European grapevine moth species, Eupoecilia ambiguella and Lobesia botrana, was investigated. An experimental setup was developed to prove oviposition preferences of both species for certain grape varieties and developmental stages based on epicuticular wax extracts. Chemical analysis of epicuticular wax patterns of four different Vitis vinifera varieties revealed differences. However, oleanolic acid was the main component on berry surface waxes and its relative amount decreased between early and late phenological stages. Furthermore, oleanolic acid was responsible for the preference of earlier phenological stages for E. ambiguella oviposition. However, ovipositional variety preferences were triggered by minor components on the wax berry layer. While the oviposition decision of L. botrana was mainly triggered by oleanolic acid, additional cues like olfactory and haptic ones were also important. The ovipositional preferences were discussed in accordance with the results of the chemical analysis in order to elucidate the role of wax compounds for oviposition stimulation.  相似文献   
960.
1. A dose-response experiment was conducted with male Korean native ducklings (KND) to evaluate the total sulphur amino acid (TSAA) requirement from hatch to 21 d of age.

2. A completely randomised design with 7 dietary TSAA concentrations (0.62%, 0.65%, 0.68%, 0.71%, 0.74%, 0.77% and 0.80%) were used with 6 replications per treatment.

3. Body weight (BW) and feed intake were measured weekly to calculate average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR). One duckling per pen (n = 6) was killed by cervical dislocation to weigh empty body and drumsticks at the conclusion of experiment.

4. BW was improved significantly with increasing TSAA content, in a non-linear manner. A significant decrease of FCR was shown with increasing TSAA contents. TSAA requirement was determined by taking a mean value after fitting the data to both a linear-plateau and a quadratic-plateau model. Estimated TSAA requirements were 0.70%, 0.70%, 0.66% and 0.70% for the maximum BW, ADG and ADFI and for the minimum FCR, respectively. Increasing TSAA content improved quantity of full body weight (FBW), empty body weight (EBW) and drumstick weight (DSW), but there was no effect on proportion of DSW in relation to EBW and proportion of EBW to FBW.

5. In conclusion, the growth of male KND during 1 to 21 d of age was improved with increasing TSAA content, suggesting optimal TSAA requirements estimated by two analysis models.  相似文献   

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