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51.
The aim of this investigation was to determine the prevalence of coccidian infections in suckling piglets and sows in Poland. The research was carried out in 14 out of 16 Polish provinces in the years 2003-2005. The investigation was conducted on three types of farms: large farms (>100 sows), medium farms (25-100 sows) and small farms (<25 sows). Diarrhoea of unweaned piglets was observed on all the examined farms. Overall, 780 litters of suckling piglets from 104 farms and 267 mother sows were examined. The faeces were analyzed with the modified McMaster method. Isopsora suis was found in 217 (27.8%) litters from 70 (66.7%) farms. Eimeria spp. was detected only in 20 (2.6%) litters from 12 (11.5%) farms. On the large farms I. suis infection was detected in 31.7% of litters whereas Eimeria spp. in 1.4% of them. On the medium sized farms I. suis was found in 18.1% of litters and Eimeria spp. in 0.6%. On the small farms I. suis was detected in only 13.2% of litters, whereas Eimeria spp. in as many as 28.9%. I. suis and Eimeria spp. oocysts were found in 18 (6.7%) and 16 (6%) sows respectively. From 72 sows producing I. suis infected piglets only 12 (16.7%) shed I. suis oocysts and as little as 4 (5.6%) shed Eimeria oocysts. In the remaining 56 sows (77.8%) no cases of coccidian infections were detected. The results of this investigation demonstrate the high prevalence of I. suis in suckling piglets on the large swine farms in Poland. 相似文献
52.
Marcin Wysokowski ?ukasz Klapiszewski Dariusz Moszyński Przemys?aw Bartczak Tomasz Szatkowski Izabela Majchrzak Katarzyna Siwińska-Stefańska Vasilii V. Bazhenov Teofil Jesionowski 《Marine drugs》2014,12(4):2245-2268
Novel, functional materials based on chitin of marine origin and lignin were prepared. The synthesized materials were subjected to physicochemical, dispersive-morphological and electrokinetic analysis. The results confirm the effectiveness of the proposed method of synthesis of functional chitin/lignin materials. Mechanism of chitin modification by lignin is based on formation of hydrogen bonds between chitin and lignin. Additionally, the chitin/lignin materials were studied from the perspective of waste water treatment. The synthetic method presented in this work shows an attractive and facile route for producing low-cost chitin/lignin biosorbents with high efficiency of nickel and cadmium adsorption (88.0% and 98.4%, respectively). The discovery of this facile method of synthesis of functional chitin/lignin materials will also have a significant impact on the problematic issue of the utilization of chitinous waste from the seafood industry, as well as lignin by-products from the pulp and paper industry. 相似文献
53.
Masternak Katarzyna Oko Sylwia Kamola Marek Ociepa Tomasz Nucia Aleksandra Kowalczyk Krzysztof 《European Journal of Forest Research》2022,141(4):617-628
European Journal of Forest Research - Increasing areas of gradation, making it difficult or impossible to perform restorations and forestations, and as causing tree crown damage, result in the need... 相似文献
54.
Foss Kamil Przybyłowicz Katarzyna E. Sawicki Tomasz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(3):383-389
Plant Foods for Human Nutrition - Herbs are characterized by a high content of biologically active substances that positively affect human health. Phenolic compounds are one of the main bioactive... 相似文献
55.
Aki Sinkkonen Sari Kauppi Veera Pukkila Hui Nan Tomasz Płociniczak Merja Kontro Rauni Strömmer Martin Romantschuk 《Journal of Soils and Sediments》2013,13(8):1430-1438
Purpose
Previous investigations—field samplings and laboratory experiments—support the hypothesis that the degradation of s-triazines is enhanced in previously exposed as compared to pristine soils in terrestrial environments. Despite this, bottlenecks of soil sampling and various soil modification practices in microcosm studies have made it difficult to guarantee that previous contamination history enhances contaminant degradation regardless of soil origin in terrestrial ecosystems. We test the hypothesis that the degradation of simazine (2-chloro-4,6-bis(ethylamino)-s-triazine) is enhanced in previously exposed soils as compared to pristine soils in 10 l buckets at the mesocosm scale.Materials and methods
We collected soil at three separate sites consisting of a previously exposed and a pristine field. At every field, soil was collected at three separate plots and simazine degradation (days 0 and 65) and the response to atzB degrader gene primers (days 0 and 110) were followed. We analyzed the results using analysis of covariance (ANCOVA). Previous exposure and field site were assessed as fixed factors and initial simazine concentration and abiotic soil conditions as covariates.Results and discussion
After the 65-day exposure, remaining simazine concentrations depended on previous exposure but not on collection site. The response to atzB gene primers was positive in all mesocosms where simazine degradation had been rapid. Soil moisture, pH, and organic matter content were insignificant. If soil moisture was not included in the ANCOVA model, previous exposure did not appear as a significant factor.Conclusions
The results support the hypothesis that simazine is degraded more rapidly in previously exposed soils as compared to pristine environments, provided that degradation genes are available. Previously exposed soil might be used to enhance the degradation of simazine in recently contaminated terrestrial soils, supposing that the central requirements for microbial growth are adequate. 相似文献56.
Kazimierz A. Orlowski Tomasz Ochrymiuk Anthony Atkins Daniel Chuchala 《Wood Science and Technology》2013,47(5):949-963
In the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. On the other hand, cutting forces (or power—more interesting from energetic point of view) could be considered from a point of view of modern fracture mechanics. Cutting forces may be employed to determine not only toughness but also shear yield strength, which are then applied in the models. Furthermore, forecasting of the shear plane angle for the cutting models, which include fracture toughness in addition to plasticity and friction, broadens possibilities of energetic effects modelling of the sawing process even for small values of the uncut chip. Mentioned models are useful for estimation of energetic effects of sawing of every kinematics. However, for band saws and circular sawing machines, the chip acceleration power variation as a function of mass flow and tool velocity ought to be included in analysis of sawing at larger cutting speeds. 相似文献
57.
Müller-Graf C Berthe F Grudnik T Peeler E Afonso A 《Fish physiology and biochemistry》2012,38(1):231-241
The Treaty of Amsterdam, in force since 1 May 1999, has established new ground rules for the actions of the European Union
(EU) on animal welfare. It recognizes that animals are sentient beings and obliges the European Institutions to pay full regard
to the welfare requirements of animals when formulating and implementing Community legislation. In order to properly address
welfare issues, these need to be assessed in a scientific and transparent way. The principles of risk assessment in terms
of transparency and use of available scientific data are probably well suited for this area. The application of risk assessment
for terrestrial and aquatic animal welfare is a relatively new area. This paper describes the work developed in the context
of the European Food Safety Authority (EFSA) opinions on the application of a risk assessment methodology to fish welfare.
Risk assessment is a scientifically based process that seeks to determine the likelihood and consequences of an adverse event,
which is referred to as a hazard. It generally consists of the following steps: (i) hazard identification, (ii) hazard characterisation,
(iii) exposure assessment and (iv) risk characterisation. Different approaches can be used for risk assessments, such as qualitative,
semi-quantitative and quantitative approaches. These are discussed in the context of fish welfare, using examples from assessments
done to aquaculture husbandry systems and stunning/killing methods for farmed fish. A critical review of the applications
and limitations of the risk methodology in fish welfare is given. There is a need to develop appropriate indicators of fish
welfare. Yet, risk assessment methodology provides a transparent approach to identify significant hazards and support recommendations
for improved welfare. 相似文献
58.
Jarosław Król Wojciech Pobłocki Tomasz Bockenheimer Piotr Hliwa 《Aquaculture International》2014,22(1):53-62
The effect of supplemented commercial diets with diethylstilbestrol (DES—15, 30 and 60 mg kg?1) and 17 β-estradiol (E2—30 and 60 mg kg?1), two chemicals commonly used in sex reversal procedure in fish, on survival and growth parameters of juvenile European catfish (Silurus glanis) was evaluated. During the two experiments, lasting 28 days each, fish were kept at temperature 25.2–26.5 °C, pH 7.4–9.3 and oxygen concentration 5.0–7.3 mg O2 dm?3. DES supplementation resulted in depressed growth rate of catfish. In experimental groups fed with E2, no negative effect on growth parameters was found. Both chemicals did not result in observed mortality. In all of the experimental DES groups, hepatosomatic index increased significantly, which suggests negative influence on physiological condition of catfish. DES supplementation significantly changed cytological factors of liver cells and caused hepatic alterations in parenchyma, such as vacuolization and blood congestion. Similarly, supplementation of E2 in food resulted in changes in cytological parameters of hepatocytes. However, E2 did not cause pathological changes within the liver tissue. Histological examination of the catfish gonads showed 19 and 38 % of sterile fish after treatment with 30 and 60 mg kg?1 of DES, respectively. The results suggest that DES served in food could be ineffective in hormonal feminization process of European catfish. No disturbances of sex differentiation process after E2 treatment were observed. However, slight feminization effect in the highest level of E2 treatment group was recorded. 相似文献
59.
Journal of Plant Diseases and Protection - The assessment of the effectiveness of resistance sources to fungal diseases is a very important issue allowing to determine the possibilities of... 相似文献
60.
A vegetation survey of semi-permanent plots was conducted between years 1955–1962 and 2005–2009, and aimed to determine floristic changes occurring in beech forests located on a scarcely populated, dense forest area. The survey encompassed all natural beech forest types within the Polish part of the “Eastern Carpathians” International Reserve of Biosphere. A comparison of trends in changes between unmanaged (Bieszczady National Park) and managed (the remaining part of the Biosphere Reserve) forests was attempted. DCA analysis was used for the determination of changes on the community level. The density of vegetation, species richness, frequency of occurrence and cover, and functional groups of species were determined. Much more profound community changes were determined to have occurred in managed beech forests. However, a similar direction in vegetation changes within both managed and unmanaged forests verifies the existence of a regional pattern of changes in beech forests. This regional pattern involves (1) a decrease in the shares of arborescent species within the shrub layer, (2) disturbance of the canopy layer, (3) acidification of the top layer of the soil, (4) change of light conditions, (5) increase in shares of generalist species and decrease in shares of specialist species. A decreasing anthropogenic pressure, aging of forest stands, functioning of large, dense forest areas and sustainable forest management strategies forestry management system mimicking natural deciduous forest disturbance regime constitute factors shaping the regional changes of the forest vegetation. The undergoing changes can lead to biotic and spatial homogenization of the Eastern Carpathian beech forests. 相似文献