In the constant pursue of the sustainability of socio-industrial systems, the definition of useful, reliable and informative, and at the same time simple and transparent, indicators is an important step for the evaluation of the circularity of the assessed systems. In the circular economy (CE) context, scientific literature has already identified the lack of overarching indicators (social, urban, prevention-oriented, etc.), pointing out that mono-dimensional indicators are not able to grasp the complexity of the systemic, closed-loop, feedback features of CE. In this respect, Emergy accounting is one of the approaches that have been identified as holding the potential to capture both resource generation and product delivery dimensions and therefore to provide an enhanced systems’ evaluation in a CE perspective.

Because of Emergy’s intrinsic definition and its calculation structure, Emergy-based indicators conceptually lend themselves very well to the evaluation and monitoring of circular processes. Additionally, Emergy has the unique feature of enabling the evaluation of systems that are not necessarily only technosphere systems, but also of technological systems which embed nature (techno-ecological systems).

The present paper gives a perspective on a set of Emergy-based indicators that we have identified as suitable to evaluate circular systems, and outlines the different perspective compared to the circularity indicators defined in the “Circularity Indicators Project” launched by the Ellen MacArthur Foundation.

Among the numerous modern, high-efficiency energy technologies allowing for the conversion of chemical energy of coal into electricity and heat, the Direct Carbon Fuel Cells (DCFC) deserve special attention. These are devices that allow, as the only one among all types of fuel cells, to directly convert the chemical energy contained in solid fuel (coal) into electricity. In addition, they are characterized by high efficiency and low emission of pollutants. The paper reviews and discusses previous research and development works, both around the world and in Poland, into the technology of direct carbon fuel cells with an alkaline (hydroxide) electrolyte.

The article discusses the importance of small hydro power plants in the Polish power system and defines the legal conditions for the operation of small hydro power plants. The phenomena occurring in the hydrological system of small hydro power plants and their impact on the natural environment were analyzed. An analysis of phenomena occurring in the hydrological system and the activity of small hydro power plants that are operating on the Radunia River helped us identify relations between different types of power plants working in cascades and possibilities of power generation control in period of several days. The above-mentioned analysis has been used in the development of a mathematical model of a hydroelectric plant and cascades of hydroelectric plants. The numerical simulations carried out concerned both the self-operating power plant and a cascade of two identical objects of this type. There is a possibility for small hydro power plant to run as a base load power plant and during periods of high demand as well (peak demand or unexpected loss of generation in the power system). A single hydroelectric power plant can deal with varying peak load demands while adding a second stage increase those abilities. A cascade of reservoir hydropower plants has a much greater ability to store energy and give it back in time. In addition, the existence of a second power plant equipped with a surge reservoir allows for a significant reduction in the amplitude of flows in the river below the cascade, which will reduce the negative impact of the cascade on the environment.

The primary aim of this paper was to assess the development of prosumer energy sector in Poland. In the first point, the basic notions connected with prosumer energy (micro-installation, prosumer) were discussed on the basis of Law of Renewable Energy Sources of February 20, 2015 (Journal of Laws, item 478, as amended) and the main aspects of the European Union energy policy where presented in the context of the development of the prosumer energy sector. In this part of the study, numerous benefits for the Polish economy and consumers of electrical energy, connected with the expansion of prosumer energy sector, were presented. On the other hand, many obstacles which stall this sector in Poland were noticed. In the second point the most important regulations from the Law of Renewable Energy Sources of February 20, 2015 were analyzed (In the second point the most important regulations from the Law of Renewable Energy Sources of February 20, 2015 (hereinafter: the RES act) were analyzed). On the basis of this legal act, the so called “rebate system”, which is currently used in Poland to support prosumers of electrical energy, was described. Moreover, many legal and administrative simplifications implemented by the RES act were indicated. The analytical approach to the RES Act in this study resulted in the detection of many regulations in this legal act which may have an adverse impact on the development of the prosumer energy sector in Poland. In the third point, programs co-financed by the Polish government or the European Union, which financially support the purchase and installation of energy technologies using RES, were described. Statistical data connected with the prosumer energy sector in Poland was presented in the fourth point of this paper. On the basis thereof, the authors attempted to find the correlation between the number of prosumers and the share of the amount of electrical energy from renewable energy sources in gross electrical energy consumption. In the fifth point issues connected with energy technologies used in the Polish prosumer energy sector were discussed. Moreover, this point focuses on the great popularity of photovoltaic modules among Polish prosumers and results in the reluctance of Polish prosumers to install wind microturbines and small hydroelectric power plants.

The national power industry is based primarily on its own energy mineral resources such as hard and brown coal. Approximately 80% of electrical energy production from these minerals gives us complete energy independence and the cost of its production from coal is the lowest in comparison to other sources. Poland has, for many decades had vast resources of these minerals, the experience of their extraction and processing, the scientific-design facilities and technical factories manufacturing machines and equipment for own needs, as well as for export. Nowadays coal is and should be an important source of electrical energy and heat for the next 25–50 years, because it is one of the most reliable and price acceptable energy sources. This policy may be disturbed over the coming decades due to the depletion of active resources of hard and brown coal. The conditions for new mines development as well as for all coal mining sector development in Poland are very complicated in terms of legislation, environment, economy and image. The authors propose a set of strategic changes in the formal conditions for acquiring mining licenses. The article gives a signal to institutions responsible for national security that without proposed changes implementation in the legal and formal process it, will probably not be possible to build next brown coal, hard coal, zinc and lead ore or other minerals new mines.

The article presents a synthetic analysis of the crude oil market in Poland. As of today, this safety is provided mainly on the basis of native lignite and hard coal resources. However, the analysis of the hard coal market conducted by the authors indicates that the carried out mining restructuring (among others) led to an excessive reduction of mining volume and employment level in the hard coal mining sector. This led to a precedent situation when Poland became an importer of this energy carrier. In addition, the European Union’s requirements for greenhouse gas emissions must be taken into account. In connection with the above, it is necessary to search for new energy sources or technologies that enable hard coal to meet the requirements. It is possible to apply the so-called clean coal technologies that allow the greenhouse gas emissions generated during coal combustion to be reduced. As of today, they are not used on a mass scale, because the use of this type of technology involves additional financial expenses. However, taking into account that technologies have been growing faster and faster, are modernized in a shorter time, making a breakthrough discovery took hundreds of years, now it is often a few months, clean coal technologies can become the optimal solution in the near future. It is also necessary to diversify the sources of obtaining imported energy carriers.

The article describes coal and crude oil in terms of their mutual substitution. The article is a continuation of research conducted by the authors. Previous publications presented considerations on analogous topics related to natural gas and renewable energy sources. The crude oil market in Poland was analyzed and forecasts for oil extraction and the demand in the world and Poland by 2023 were presented. The SARIMA model was also created. The model made it possible to obtain oil an prices forecast.

The aim of the article is to present the issue of risk and related management methods, with a particular emphasis on the conditions of investment in energy infrastructure. The work consists of two main parts; the first one is the theoretical analysis of the issue, while the second discusses the application of analysis methods on the example of the investment in an agricultural biogas plant. The article presents the definitions related to the investment risk and its management, with a particular emphasis on the distinction between the risk and uncertainty. In addition, the main risk groups of the energy sector were subjected to an analysis. Then, the basic systematics and the division into particular risk groups were presented and the impact of the diversification of investments in the portfolio on the general level of risk was determined. The sources of uncertainty were discussed with particular attention to the categories of energy investments. The next part of the article presents risk mitigation methods that are part of the integrated risk management process and describes the basic methods supporting the quantification of the risk level and its effects – including the Monte Carlo (MC), Value at risk (VaR), and other methods. Finally, the paper presents the possible application of the methods presented in the theoretical part. The investment in agricultural biogas plant, due to the predictable operation accompanied by an extremely complicated and long-term investment process, was the subject of the analysis. An example of “large drawing analysis” was presented, followed by a Monte Carlo simulation and a VaR value determination. The presented study allows for determining the risk in the case of deviation of financial flows from the assumed values in particular periods and helps in determining the effects of such deviations. The conducted analysis indicates a low investment risk and suggests the ease of similar calculations for other investments.

The events that took place on April 10,2010 on the Gulf of Mexico began an international debate on minimizing and materializing the risk of dangerous occurrences and accidents during the exploitation of offshore energy resources. In the aftermath of this event to ensure safe operation in European maritime areas, the European Union decided to introduce regulations throughout the entire EU. On June 12, 2013, Directive 2013/30/EU of the European Parliament and of the Council on safety of offshore oil and gas operations and amending Directive 2004/35/EC was issued. The main aim of the Directive is to reduce the occurrence of major accidents relating to offshore oil and gas operations and limits their consequences. The article is a review of provision of Directive 2013/30/UE with particular regard to requirements at the national level. What is more, the paper indicates solutions which must be introduced by July 19, 2018 in offshore companies. The incorporated solutions must include the protection of the marine environment against pollutions (especially oil spills), establish minimum conditions for safe offshore exploration and the production of oil and gas and improve the response mechanism in the eventof an accident. The paper also presents accidents which take place in oil and gas fields which are a background of necessary improvements of safety during offshore operations.

This article, as far as possible based on the available literature, empirical measurements, and data from mesoscale models describes and compares expected wind conditions within the Baltic Sea area. This article refers to aspects related to the design and assessment of wind farm wind resources, based on the author’s previous experience related to onshore wind energy. The consecutive chapters of this publication are going to describe the present state and the presumptions relating to the development of wind energy within the Baltic Sea area. Subsequently, the potential of the sea was assessed using mesoscale models and empirical data from the Fino 2 mast that is located approximately 200 kilometers away from the majority of areas indicated in the Polish marine spatial development plan draft of Poland for offshore wind farm development (Maritime Office in Gdynia 2018). In the chapter describing mesoscale models, the author focused his attention on the GEOS5.12.4 model as the source of Modern-Era Retrospective Analysis for Research and Application 2 data, also known as MERRA2 (Administration National Aeronautics and Space Agency, 28), which, starting from February 2016, replaced MERRA data (Thogersen et al. 2016) and have gained a wide scope of applications in the assessment of pre-investment and operational productivity due to a remarkable level of correlation with in-situ data. Model-specific data has been obtained for eight locations, which largely overlap with the locations of the currently existing offshore wind farms within the Baltic Sea area. A significant part of this publication is going to be devoted to the description of the previously mentioned Fino 2 mast and to the analysis of data recorded until the end of 2014 by using the said mast (Federal Maritime and Hydrographic Agency 2018). The analysis has been carried out by means using scripts made in the VBA programming language, making it easier to work with large chunks of data. Measurements from the Fino 2 mast, together with long-term mesoscale model-specific measurements can be used, to some extent, for the preliminary assessment of wind farm energy yield in the areas designated for the development of renewable energy in the Polish exclusive maritime economic zone (Maritime Office in Gdynia 2018). In the final part of this article, pieces of information on the forecasted Baltic Sea wind conditions, especially within the exclusive economic zone of Poland, are going to be summarized. A major focus is going to be put on the differences between offshore and onshore wind energy sources, as well as on further aspects, which should be examined in order to optimize the offshore wind power development.

Increasing the share of energy production from renewable sources (RES) plays a key role in the sustainable and more competitive development of the energy sector. Among the renewable energy sources, the greatest increase can be observed in the case of solar and wind power generation. It should be noted that RES are an increasingly important elements of the power systems and that their share in energy production will continue to rise. On the other hand the development of variable generation sources (wind and solar energy) poses a serious challenge for power systems as operators of unconventional power plants are unable to provide information about the forecasted production level and the energy generated in a given period is sometimes higher than the demand for energy in all of the power systems. Therefore, with the development of RES, a considerable amount of the generated energy is wasted. The solution is energy storage, which makes it possible to improve the management of power systems. The objective of this article is to present the concept of electricity storage in the form of the chemical energy of hydrogen (Power to Gas) in order to improve the functioning of the power system in Poland. The expected growth in the installed capacity of wind power plants will result in more periods in which excess energy will be produced. In order to avoid wasting large amounts of energy, the introduction of storage systems is necessary. An analysis of the development of wind power plants demonstrates that the Power to Gas concept can be developed in Poland, as indicated by the estimated installed capacity and the potential amount of energy to be generated. In view of the above, the excess electricity will be available for storage in the form of chemical energy of hydrogen, which

Concentrations of four trace elements, copper (Cu), zinc (Zn), manganese (Mn) and seleni- um (Se), have thus far proven to be affected by lentiviral infections in people and rhesus monkeys. As small ruminant lentivirus (SRLV) infection is responsible for one of the most important goat diseases, caprine arthritis-encephalitis (CAE), we evaluated serum and liver concentrations of Cu, Zn, Mn, Se in goats severely affected by symptomatic CAE and compared them with litera- ture reference intervals. Serum and liver samples of dairy goats euthanized due to severe clinical form of CAE were collected and screened for the concentration of Cu, Zn, Mn (54 serum sam- ples, 22 liver samples), and Se (36 serum samples, 22 liver samples) using flame atomic absorption spectrometry for Cu, Zn, Mn and graphite furnace atomic absorption spectroscopy for Se. In both serum and liver samples concentration of Zn was the highest, followed by Cu concentration, and then by Mn and Se. There was no relationship between serum and liver concentrations of trace elements. Liver concentrations of all four trace elements and serum Cu concentration fell within literature reference intervals, although liver Se concentration was mainly in the lower marginal range (between 0.4 and 1.0 mg/L). Serum Zn concentration was elevated (>1.2 mg/L) in all goats, serum Mn concentration was elevated (>0.04 mg/L) in 42 (78%) goats and serum Se concentra- tion was elevated (>1.6 mg/L) in 13 (36%) goats. Concluding, severe symptomatic CAE does not appear to be associated with the level of any of the four trace elements.

The use of lactoferrin (LF) and/or lactobacillus sp. (LB) to improve animal health and production has increased recently. However, information regarding the immune-modulatory role of LB supplementations either alone or in combination with LF in sheep remains unclear. Therefore, the present study was designed to evaluate the immune modulating properties and the antioxidant activity of supplementing commercially available LF and/or LB in healthy lambs. For this reason, twenty-four apparently healthy Ossimi lambs were used. After three weeks of acclimatization, the lambs were randomly allocated to four equal-sized groups and assigned to receive one of the following supplements: LB at a dose of ~ 1 g active ingredient/head (group 1), LF at a dose rate of 0.5 gm /head (group 2), a combination of both treatments using the same dosing regimens (group 3), and (group 4) received only 10 mL of isotonic saline and was considered as a control group. All supplements were given orally twice daily for 30 consecutive days. Blood samples were collected from each lamb before starting the experiment (T0) and two weeks (T15), and four weeks (T30) after giving supplements for hematological examinations, serum biochemical analyses, and RT-PCR assays. Our findings demonstrated that lambs receiving LB showed statistically significant (P<0.05) higher values of total leucocytes, lymphocytes and lysozyme activity than those receiving LF. In contrast, lambs that received LF had significantly (P< 0.05) higher values of serum catalase, nitric oxide and GSH with a significantly lower MDA level compared with those supplemented with LB. A combination of LF and LB supplementation elicited maximal up-regulation of Tollip, TLR4, IL-5, and IL-6 gene expression compared with other groups. The results suggest that bovine LF and or LB could be used as useful nutritional supplements to support the immune system in healthy lambs.

The normotensive (Wistar) and spontaneously hypertensive (SHR) rats were examined to assess the response of the organism to selenium (Se) overdose. Moreover, the effect of zinc (Zn) and vitamin E, i.e. dietary components interacting in many biochemical processes with Se, on the Se uptake was evaluated. The control group was fed an untreated diet, and the diets of two other groups were overdosed with Se in the form of sodium selenite (9 mg/kg) and supplemented with Zn (13 mg/kg). Two experimental groups were fed a diet supplemented with Zn (13 mg/kg) and Se at an adequate level (0.009 mg/kg); a half of the animals was supplemented with vitamin

E. The results showed significant differences in the Se contents between the rat strains in case of Se-overdosed groups, where in the liver and kidney tissue Se contents of SHR rats exceeded 3- and 7-fold the normotensive ones. The Se uptake was altered by the vitamin E; no effect of Zn was observed. Activities of antioxidant enzymes were determined in the animal tissues indicating different patterns according to rat strain, tissue analysed, and administered Se dose. Thus, Se overdose, for instance, via an incorrectly prepared dietary supplement, can result in serious imbalances of the biochemical status of the animals.

Polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its metabolite, dichlorodiphenyldichloroethylene (DDE) can disturb the secretory function of the ovary and both contractions and secretory function of the uterus during the estrus cycle and pregnancy. Additionally, PCBs can pass through the placental barrier into allantoic and amniotic fluid. The presence of PCBs in these fluids is associated with higher frequency of spontaneous abortions and premature births in humans and animals. Therefore, the effect of PCBs, DDT and DDE on the connexins (Cx26, Cx32 and Cx43) and keratin 8 (KRT8) expression in bovine placentomes was investigated. The placentome slices from the second trimester of pregnancy were incubated with PCB153, 126, 77, DDT and DDE (each at doses of 1, 10 or 100 ng/ml) for 48 h. Then, the slices were stained using immunohistochemistry. The density of Cxs staining was measured with Axio- Vision Rel. 4.8 software in fetal-maternal connections and binuclear cells (BNC). None of the tested xenobiotics (XBs) affected the localization of Cxs and KRT8 in the fetal-maternal connection area, but the XBs affected the density of Cxs in fetal-maternal connections and binuclear cells (BNCs). Depend on the doses, in fetal-maternal connections all used PCBs changed the protein expression of different Cxs, while in BNCs, all tested XBs except DDT increased the expression of Cxs. None of investigated XBs affected on KRT8 expression. In summary, used XBs affect the expression of Cxs and change the quantitative relationships between them. Therefore, XBs can unfavorably influence function of the utero-placental barrier in cows.

Enterococcus hirae belongs in the Enterococcus faecium group within the genus Enterococcus. This species occurs naturally in the environment, commensally in the alimentary tracts of animals, and pathologically for example in humans with urinary infections. Some strains of E. hirae possess virulence factors, including biofilm formation. Biofilm growth protects bacteria against host de- fences; biofilm can be a source of persistent infection. Testing bacterial strains for their ability to form biofilm might therefore facilitate their treatment or prevention. This study focuses on bio- film formation by E. hirae strains derived from various animals. This kind of testing has never been done before. A total of 64 identified E. hirae from laying hens, ducks, pheasants, ostriches, rabbits, horses and a goat were tested by means of three methods; using Congo red agar, the tube method and microtiter plate agar. The majority of strains were found to form biofilm. 62.5% of strains were biofilm-forming, four categorized as highly positive (OD570 ≥1); most strains were low-grade biofilm positive (0.1 ≤ OD 570 < 1). Related to poultry, 55 E. hirae strains were tested nd found to produce biofilm; 24 strains did not form biofilm, 31 strains were biofilm-forming; 27 strains showed low-grade biofilm formation, and four strains were highly biofilm-forming. Four strains from hens and ostriches reached the highest OD570 values, more than 0.500. Rabbit-derived E. hirae strains as well as strains isolated from horses and the goat were low-grade bio- film-forming. Microtiter plate assay proved to be the best tool for testing the in vitro biofilm for- mation capacity of E. hirae strains from different species of animals.

Early recognition of altered lactate levels is considered a useful prognostic indicator in dis- ease detection for both human beings and animals. It is reasonable therefore to hypothesize that a portable, point of care (POC) spectrophotometric device for analysis of lactate levels, may have an application for field veterinarians across a range of conditions and diagnostic procedures. In this study, a total of 72 cattle in the transition period underwent POC spectrophotometric lactate measurement with a portable device (The Vet Photometer) in the field, with a small portion of blood used for comparative ELISA evaluation. Lactate measurements were compared using a of Passing-Bablok regression analysis and Bland-Altman plots. The Vet Photometer lactate mea- surement results were in agreement with those generated by the ELISA method. Values for the agreement were derived, in a 95% CI between -1.3 and 0.99, and a positive correlation (r=0.71) between the two measurements. The equation y= 0.68x + 0.60 was achieved using a Pass- ing-Bablok regression analysis. There were no statistical differences in mean values between the measurement methods. In conclusion, a novel veterinary POC spectrophotometric device “Vet Photometer” is an accurate device for evaluation of lactate levels in healthy transition cows.

The presence of lipopolysaccharide (LPS) in blood induces an inflammatory response which leads to multiple organ dysfunction and numerous metabolic disorders. Uncontrolled, improper or late intervention may lead to tissue hypoxia, anaerobic glycolysis and a disturbance in the acid -base balance. The effects of LPS-induced toxemia on biological and immunological markers were well studied. However, parameters such as base excess, ions, and acid-base balance were not fully investigated. Therefore, the objective of this study was to examine these blood parameters collectively in LPS-induced inflammatory toxemia in rat’s model. After induction of toxemia by injecting LPS at a rate of 5 mg/kg body weight intravenously, blood was collected from the tail vein of twenty rats and immediately analyzed. After 24 hours, the animals were sacrificed and the blood was collected from the caudal vena cava. The results revealed that the levels of pH, bicarbonate, partial pressure of oxygen, oxygen saturation, Alveolar oxygen, hemoglobin, hematocrit, magnesium (Mg2+), and calcium (Ca2+) were significantly decreased. On the other side, the levels of Base excess blood, Base excess extracellular fluid, partial pressure of carbon dioxide, lactate, Ca2+/Mg2+, potassium, and chloride were significantly increased compared to those found pre toxemia induction. However, sodium level showed no significant change. In conclusion, Acute LPS-toxemia model disturbs acid-base balance, blood gases, and ions. These parameters can be used to monitor human and animal toxemic inflammatory response induced by bacterial LPS conditions to assist in the management of the diagnosed cases.

The main objective of this study was to evaluate the intensity and character of the inflammatory reaction caused by an innovative polyester-polyurethane vascular prosthesis implanted into the abdominal aorta of 9 Beagle dogs aged 1-3 years. At 6 and 12 months post implantation the prostheses were removed and tissues samples were examined using 2 methods: histology and immunohistochemistry (IHC). Histology slides stained with hematoxylin and eosin (H&E) were evaluated for the intensity of inflammation by observing the density of inflammatory cells and graded 1 to 4 (1- light inflammation, 4 – severe inflammation). The pro-inflammatory mediator tumor necrosis factor-alpha (TNFα) and two anti-inflammatory mediators, interleukin 1 receptor antagonist (IL1ra), and interleukin 10 (IL10), were also assessed in the tissue samples by IHC methods. Mean (n=5) inflammation grade in H&E slides at 6 months post-implantation (6Mpost) was 2 and mean (n=4) inflammation grade at 12 months (12Mpost) was almost 3. IHC staining showed that TNFα and IL1ra in tissue samples obtained from 6Mpost dogs were expressed at the same intensity indicating equal pro- and anti-inflammatory cytokine levels. However, in the 12Mpost tissues TNFα was expressed more intensely than IL1ra and IL10. Moreover, in 2 dogs at 12Mpost, there were signs of infection assessed on the basis of neutrophil infiltration in the prostheses. In conclusion, the assessment of pro-inflammatory mediators such as TNFα and anti-inflammatory mediators, such as IL1ra and IL10, can help to interpret the intensity of the inflammatory process directed at synthetic prostheses.

Dendritic cells (DCs) due to their ability to present antigens are essential during the immune response to infections. The aim of the study was to evaluate the influence of bovine leukaemia virus (BLV) infection on DC properties. Cytokine profiles of myeloid, plasmacytoid and mono- cyte derived DCs from BLV infected cattle were analysed. Concentrations of IL-6, IL-10, IL-12, IFN-γ, and TNF-α in DC cultures were measured by flow cytometry. Obtained results indicated activation of pDCs population, where a significant increase in production of the IFN-γ was shown. Meanwhile, a decrease in production of IFN-γ and increase in production of IL-10 were shown in mDCs; the main population responsible for antigens presentation. This may indicate a contribu- tory role of the population during the process of persistent infection. In MoDCs population a significant elevation in secretion of proinflammatory cytokines – IL-6 and TNF-α was noted.

Myxomatous mitral valve disease (MMVD) is a cardiac condition commonly found in older dogs. The disease process can lead to heart failure (HF). In HF, an increase of reactive oxygen species (ROS) and abnormal mitochondrial activity, as well as apoptosis, have been reported. Humanin (HN) is a polypeptide that has a cardioprotective effect against apoptosis and oxidative stress. The purposes of this study were (1) to investigate the potential role of plasma HN as a cardiac biomarker to predict disease progression of MMVD, and (2) to compare plasma HN concentrations with plasma NT-pro BNP concentrations. Thirty-one dogs were included in the study. The dogs were separated into four groups: Group 1 was healthy dogs (n = 8), Group 2 was MMVD class B (n = 8), Group 3 was MMVD class C (n = 8), and Group 4 was MMVD class D (n = 7). All dogs were given a physical examination, thoracic radiography, echocardiography, and samples of their blood were collected for hematology and blood chemistry analysis. Levels of plasma HN and plasma NT-proBNP were also investigated. The results showed that plasma HN levels were lower in the dogs with MMVD and that lower plasma HN levels were associated with greater severity of MMVD-induced HF. It was possible to observe changes in plasma HN levels at a less severe disease stage than plasma NT-proBNP in dogs with MMVD. These findings sug- gest that a decreased plasma HN level can be used as a biomarker to identify dogs with MMVD -induced HF.

Mechanical ventilation (MV) is a supportive and life-saving therapy, however, it can cause ventilator-induced lung injury as a common complication. Thus, recruitment manoeuvres (RM) are applied to open the collapsed alveoli to ensure sufficient alveolar surface area for gas exchange. In the light of the fact that positive pressure ventilation is currently the standard treat- ment for improving pulmonary function, extrathoracic negative pressure is considered as an alter- native form of respiratory support. The aim of this study was to estimate the proinflammatory and oxidative response during MV and lung injury as well as the response after RM. All studied parameters were assessed at the following time points: T1-spontaneous breathing, T2- MV, T3- lung injury, T4 –RM. During MV (T2) elastase, MPO, ALP release, nitrite and superoxide generation significantly increased, whereas in later measurements a decrease in these values was noted. The MDA plasma concentration significantly (p<0.05) increased at T2, reaching a level of 13.30±0.87 nmol/ml; at other time points the values obtained were similar to the baseline value of 9.94±0.94 nmol/ml, whereas a gradual decrease in SOD activity at time T2-T4 points in comparison with the baseline value was found. During the study both neutrophil activity and oxi- dative stress indicate exacerbated response after MV and lung injury by bronchoalveolar lavage; however, extrathoracic negative pressure system as the MR ameliorates damaging changes which could further lead to serious lung injury.

The aim of this study was to measure serum neopterin and C-reactive protein (CRP) concen- trations in female dogs with mammary tumours and evaluate the association between the values of these indicators and some clinical characteristics of the tumour. Fifty three female dogs were used for this study, including 43 dogs with mammary gland tumours (10 benign and 33 malignant) and 10 healthy controls. The concentrations of neopterin and CRP were determined using the ELISA technique and commercial ELISA kits. The mean serum neopterin concentration in fe- male dogs with mammary tumours was lower than in healthy dogs, but significant difference was not found. Similarly, there were no significant differences in neopterin concentrations in female dogs based on tumour size, tumour ulceration and metastasis. The mean CRP concentration was significantly higher (p<0.05) in dogs with malignant tumours compared to dogs with benign tu- mours and control. Furthermore, serum CRP concentration was significantly higher (p<0.05) in dogs with metastatic malignant tumours compared to dogs with non-metastatic mammary tu- mours. The CRP concentration was significantly lower (p<0.05) in dogs with tumours less than 3 cm compared to those with larger tumours, and significantly higher in dogs with ulcerated tu- mours compared to those without ulceration. Our findings suggest that the neoplastic process in the mammary gland does not cause significant changes in serum neopterin concentrations in dogs. Higher concentrations of serum CRP in dogs with advanced stages of malignant tumours may suggest that CRP could be a potential prognostic marker in canine malignant mammary tu- mours, but this hypothesis needs further study.

In this study, we propose a possible way of obtaining reproductive and respiratory syndrome virus (PRRSV) free offspring from genetically valuable lines of Přeštice black-pied boars com- ming from PRRSV-positive pig breeding herds with the use of artificial insemination (AI). The ejaculates were collected from 4 different lines of boars. Samples of fresh semen were not detected with the virus and 12 sows were inseminated. Blood samples of sows and their offspring were repeatedly tested for the virus but the results were negative. We managed in this way to maintain the endangered population of this breed and obtain PRRSV-free offspring.