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The aim of the study was to determine the interaction of herbicides and herbicides with biostimulants on the accumulation of dry matter and starch in potato tubers. In a three-year field experiment based on the method of randomised sub-blocks, two factors were taken into account. The first factor were potato cultivars: Bartek, Gawin, Honorata. The second factor were five methods of herbicides and biostimulants application: (1) the control object without chemical protection (CO); (2) herbicide linuron + clomazone (Harrier 295 ZC) (H); (3) herbicide linuron + clomazone (Harrier 295 ZC) and biostimulant Ecklonia maxima (Kelpak SL) - (H + K); (4) herbicide metribuzin (Sencor 70 WG) - (S); (5) herbicide metribuzin (Sencor 70 WG) and biostimulant sodium para-nitrophenol, sodium ortho-nitrophenol, sodium 5-nitroguaiacol (Asahi SL) - (S + A). The cultivars and weather conditions significantly affected the content and yields of dry matter and starch. The herbicides and biostimulants used determined the starch accumulation as well as dry matter and starch yields. Most starch in tubers (more by 3.7 g/kg) and the highest dry matter and starch yields (more by 2.87 and 1.79 t/ha, respectively), compared to the control object, were obtained after the application of the herbicide Sencor 70 WG and biostimulant Asahi SL.

A continuous long-term field experiment (2008-2018) was conducted in Xinjiang, north-western China, to assess the impact of farmyard manure (FYM) and inorganic fertilisers on the sustainable biomass yield of sweet sorghum cultivar (Xingaoliang No. 3) and soil chemical properties. Seven treatments, associated with nitrogen (N), phosphorus (P), potassium (K), FYM, and their different combination, were compared with the control plot (CK). As a result, the treatments NP, PK, NK, NPK and NPKM significantly increased the average biomass yields by 30-48% over CK. The 12 t/ha FYM per year with NPK (NPKM) increased both the yield and total soluble solids (T_SS) by 48% and 7.9%, respectively, while the 18 t/ha/year application rate of FYM had an adverse effect on yield. Stem T_SS, soil available N and K for all treatments decreased while soil organic carbon, soil total salt and the available P for FYM applied treatments increased over the years. The soil pH stabilised at 7.8-8.2 at the end. In conclusion, the 12 t/ha/year of FYM is the most efficient rate for a single application or incorporation with inorganic fertilisers. A more reasonable application rate of N and K fertiliser to increase the yield and irrigation rate to reduce soil salt needs for further investigation.

A straw chopper is a mechanical device used to uniformly chop fodder into small pieces to mix it together with other grass and then feed it to livestock. The objective of this research was to design and develop an animal fodder chopping machine to be utilised by dairy farmers within their purchase range. The drawing of these machine parts was undertaken in AutoCAD software and the construction was performed in a local workshop. After development of this machine, performance tests were carried out on a farm. The chopping machine tests were carried out with commonly grown fodder (namely: straw, grass, and maize) in Bangladesh. The performance evaluation of the developed machine was carried out in terms of the chopping efficiency, machine productivity, and energy consumption. The economic analysis of the straw chopping machine was assessed by indicating the cost effectiveness to the poor farmers. Analysis of the data in regard to chopping efficiency and machine productivity varied from 93 to 96% and from 192 to 600 kg×h^-1, respectively. The energy consumption during the chopping process ranged between 0.0025 and 0.01 kWh for the different types of fodder. The break-even point of the fodder chopping machine was 3 793 kg of cut straw and the payback period was within one year depending on the use.

In this study, activated carbon derived from Monotheca buxifolia waste seeds was used for the adsorptive removal of a number of selected azo dyes such as Eriochrome Black T (EBT), Remazol brilliant blue (RBB), Remazol yellow (RY) and Remazol brilliant orange (RBO) from an aqueous solution by changing the initial dye concentration, adsorbent dosage, solution pH, contact time and temperature. A Fourier transform infrared spectroscopic analysis of the activated carbon showed the existence of hydroxyls, methyl, methylene, carbonyls, alkane and alkenes groups while the scanning electron microscopic image displayed the gradual formation of cavities and open pores on the surface. The results showed that as the amount of the adsorbent and the shaking time were increased, the removal percentage of the dye increased accordingly. Higher adsorption percentages were observed at a lower dye concentration and temperature in an acidic media at a pH range (1-5). The investigated data were evaluated with the Langmuir and Freundlich adsorption models. The maximum adsorption capacities obtained from the Langmuir model were 112.36, 96.34, 97.65 and 90.91 mg/g for EBT, RBB, RY and RBO, respectively. The results indicated that the electrostatic interaction was the main cause of the adsorption of these anionic azo dyes on the surface of the activated carbon.

Gravel mulching is a characteristic agricultural technique that has been used for hundreds of years in the north-western Loess Plateau of China. However, the effects of the gravel-sand mulch on the processes of the runoff, soil erosion, and nutrient losses are neither fully distinguished nor even known in many parts of the world. This study investigated how different gravel particle sizes in the mulch affected the runoff, erosion as well as the extent of the nutrient losses in the surface runoff. The laboratory experiments were conducted using a rainfall simulator with three gravel mulch treatments: (1) fine gravel mulch (FG); (2) medium gravel mulch (MG); (3) coarse gravel mulch (CG) and a control group, bare soil (BS). The results of these rainfall simulation experiments gave estimates on how the grain size influences the runoff and losses of the soil and its nutrients. Applying the gravel mulch significantly delayed the runoff's starting time when compared with the bare soil. Both the total runoff and soil loss increased with the grain size of the gravel mulch. Compared with the bare soil, the lowest surface runoff and soil loss was observed from the fine gravel treatment. These results clearly show that gravel mulch plays an important role in the runoff and sediment generation processes, and that it significantly reduces the surface runoff and soil loss. The losses of the total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) from the bare soil were much higher than those under the gravel mulching. The fluctuations in these nutrient-loss processes were the most intense in the CG treatment, while the TC content, in initial runoff, was significantly higher in the FG than the other treatments. Our findings suggest gravel mulch is a useful water and soil conservation technique in the loess area of north-western China, and these results can inform one on the theoretical principles for properly utilising gravel-mulched fields.

Electrokinetic remediation (EKR) is a powerful technique aimed at pollutant removal in soil, sludge, mine tailings, and so on. In the current work, we performed a bibliometric analysis of the research on EKR for the period of 1900-2018 on the basis of the core database of the Science Citation Index Expanded. In addition to a basic analysis of the research characteristics, keywords were analysed for four major participants: USA, China, Spain, and South Korea. The periods of 1990-2001, 2002-2008, and 2009-2018 were studied using the keyword analysis method to gain insights into the development of EKR and predict its future trends. The results revealed that the related research field in the USA was broad during the study periods. Meanwhile, China was interested in fluorine pollution and contamination in red soil. Spain paid close attention to pollution due to agricultural contamination. South Korea focused on radioactive element pollution. The number of papers published over a period of 28 years increased steadily and continued to rise after 2008. The combined techniques of EKR + phytoremediation and EKR + bioremediation were successively utilised by scholars over time, and the latter is expected to demonstrate vitality in the future.

A total of 29 520 animals, from 164 batches of pigs belonging to an identical number of herds, were involved in the study. The considered population of pigs were limited to the region of north-eastern Poland involving six voivodeships. From each herd, samples of blood were collected to evaluate the antibody titres to Mycoplasma hyopneumoniae, porcine reproductive and respiratory syndrome virus, Aujeszky's disease virus and swine influenza virus. At an abattoir, the lung lesions of each batch were scored and the enzootic pneumonia-like lesion average value was calculated. Lesions, indicative of enzootic pneumonia, were found in 57.8% of the lungs. For all lungs, the enzootic pneumonia-like lesion average value was 1.74, ranging from 0.42 to 3.56 among the 164 batches. In the examined pig population, 57.8% were considered suffering from swine respiratory disease, the majority of the affected pigs came from the Podlaskie (21.7%) and Greater Poland (17.25%) voivodeships. In the most affected voivodeships, 88.37% and 85.16% of the farms were considered as disease-susceptible for Greater Poland and Podlaskie, respectively. The findings indicate that, in pigs in north-eastern Poland, the major pathogens causing pneumonia-like lesions are Mycoplasma hyopneumoniae (68.9%) and porcine reproductive and respiratory syndrome virus (44%).

The aim of the study was to trace the presence of the internal carotid artery in the system of cerebral arteries of the domestic cat and to determine the role of this artery in supplying blood to the brain in ontogenesis. The available publications provide ambiguous or even contradictory information. The authors of some studies claim that there is no extracranial segment in the domestic cat's internal carotid artery. Other authors reported the internal carotid artery in the arterial pattern of the encephalon base. The study was conducted on sixty-one domestic cats: fifteen foetuses, sixteen juvenile cats, and thirty adult cats were analysed. The internal carotid artery - a vessel with a relatively large lumen - was fully preserved in all the foetuses and most of the juvenile animals. This artery was not complete with regard to the adults and some juvenile individuals, because it had lost the extracranial segment as a result of the obliteration process. A precise description of this area is not only of biological, but also of clinical, significance. The knowledge of the anatomical structure of cerebral vessels is particularly important to correctly interpret images obtained during diagnostic tests and to conduct surgical procedures correctly.

The use of in vitro (fish cell lines) is a cost-effective, very rapid, and informative tool for toxicological assessments. Using the neutral red (NR) assay, we compared the in vitro acute toxicity (20hEC50) of twenty-six chemical substances on a rainbow trout gonad cell line (RTG-2) with their in vivo acute toxicity to Barbados Millions Poecilia reticulata (48hLC50, OECD 203) and crustacean Daphnia magna (48hEC50, OECD 202). The 20hEC50 values obtained by the NR assay were higher in nearly all the cases when compared to the 48hLC50 in P. reticulata and the 48hEC50 in D. magna, indicating that the sensitivity of the RTG-2 cell line was lower compared to P. reticulata and D. magna. A high (r = 0.89) and significant (P < 0.001) correlation was recorded between the 20hEC50 values of the RTG-2 and the 48hEC50 values of D. magna. The correlation between the 20hEC50 values of the RTG-2 and the 48hLC50 values of P. reticulata was lower (r = 0.65; P < 0.001), but also significant. The authors recommend use of the NR assay on the RTG-2 cell lines as a screening protocol to evaluate the toxicity of xenobiotics in aquatic environments to narrow the spectrum of the concentrations for the fish toxicity test.

The aim of this study was to report the outcome of the use of an external fixator to treat a pelvic canal stenosis in a 5-month-old female cat. The cat was referred with a history of 3 weeks of intermittent signs of constipation refractory to the medical management, occurring after surgical treatment for a bilateral sacroiliac luxation and sacral fracture. The clinical examination revealed instability of the pelvis and a radiograph showed a pelvic canal stenosis and megacolon. External fixator was the method of choice to be used in this case. The manually applied tension on an external fixator resulted in a widening of the pelvic canal. At 45 days after surgery, there were no signs of constipation, and the radiological examination showed progressive bone healing. At 18 months post-op, the cat had no abnormalities both on the clinical examination and on the radiography. In conclusion, the use of an external fixator led to the widening of the pelvic canal using a minimally invasive procedure. To the authors' knowledge, this case report represents the first surgical description and clinical outcome of the widening of the pelvic canal in cats using an external skeletal fixator.

The presence of a significant quantity of gas in the gastrointestinal tract may hinder a proper ultrasonographic examination of the abdominal organs. The objective of this study was to investigate the influence of simethicone and fasting on the quality of ultrasonographic examinations of the gastrointestinal tract and the small organs in the abdominal cavity. Fourteen clinically healthy dogs were examined repeatedly after four different preparation protocols. The visualisation of the organs was assessed subjectively with a 3-point scoring system. The administration of simethicone is superior in the visualisation of the ileum, the ileocolic junction, the pancreas (body and right lobe), the jejunal lymph nodes, and both adrenal glands when compared to no preparation. The combination of the oral administration of simethicone and fasting is superior in the visualisation of the pylorus, the duodenum, the jejunum, the ileum, the ileocolic junction, the pancreas (body, right and left lobe), the jejunal lymph nodes, and both adrenal glands when compared to no preparation. The conclusion and clinical relevance from this exploratory study suggest that the oral administration of simethicone and fasting before an ultrasonographic examination significantly improve the visualisation of some abdominal organs.

The purposes of this pilot study were to explore the temperature changes of the paw pads in healthy cats before and after a 6-min walking test (6MWT), and to further compare the accuracy of the point and line region of interest (ROI) selection methods of the thermal imaging. Five healthy intact cats were recruited and trained to run on the treadmill, and to keep still during the standing phase on a glass panel when capturing thermographic imaging data. The paw pad temperature was recorded using a thermal camera and then analysed using both the point and line ROI before and after the 6MWT. The symmetry index (SI) between the limbs (left and right) was further calculated. Compared to the baseline, there were significant increases in the paw pad temperature of the forelimbs (point of left P < 0.001, point of right P = 0.048, point of average P = 0.002, line of left P < 0.001, line of right P = 0.007, line of average P < 0.001), hindlimbs (point of left P < 0.001, point of right P < 0.001, point of average P < 0.001, line of left P < 0.001, line of right P < 0.001, line of average P < 0.001), and average value after the 6MWT both using the point and line ROI selection methods. However, there is no temperature difference between the point and line ROI either before or after the 6MWT. In addition, no difference in the SI was found between the baseline and post-test or between the point and line ROI. These results preliminarily indicated that a 6WMT and thermal imaging could be a good combination for further clinical practices to recognise lameness or any other gait disabilities in cats, and both the point and line ROI selection methods can be considered when analysing thermographic data.

Tumour of the oral cavity is a rare condition in young animals. The most frequent are odontomas - locally invasive tumours with no metastatic potential. The article describes a case report of 4-month-old male puppy diagnosed with mandibular odontoma with cystic appearance. Authors present clinical features, histopathological examination of odontoma and the surgical management using deep curettage and hydroxyapatite granules deposition. Odontomas can form bone cyst-like structure padded with membrane forming denticles. A deep curettage is acceptable method of treatment but should be supplied with hydroxyapatite deposition if the cyst is present.

We herein report the magnetic resonance imaging (MRI) findings in a brain meningioma in a pet rat (Rattus norvegicus domestica). A 1.5-year-old pet rat was referred for depression, ataxia, tremors and bilateral nystagmus; a brain MRI was elected suspecting an intracranial neoplasia. The study was performed with a 0.25 T scanner. The MRI revealed a well-defined oval mass with a heterogeneous appearance, hyperintense in T1 and T2, and with extra-axial localisation and severe brain compression, the mass appeared strongly and diffusely contrast-enhancing. Euthanasia was elected, with the necropsy confirming the presence of a voluminous extra-axial mass. Histologically, a well-differentiated, benign meningotheliomatous meningioma was diagnosed, with the histochemical stains allowing one to exclude a granular cell tumour. To the best of our knowledge, this is the first report of MRI investigations on a pet rat intracranial meningioma.

In this study, we investigated whether the mathematical formulas, which generally reveal the external quality characteristics of living organisms, yield the correct results in goose eggs. For this purpose, three genotypes and 555 eggs were studied that were grouped into Native (n = 356), Chinese (n = 163) and Linda (n = 36), which were raised in Aksaray province. The averages in the Native, Chinese and Linda geese were 5.43, 5.38 and 5.7 cm, respectively, in breadth; were 8.12, 8.03 and 8.67 cm in length, respectively; the shape index was 66.9, 67.2 and 66.7 cm, respectively; the egg volume was 142.8, 138.8 and 172.5 cm³, respectively; the egg surface area was 136.9, 134.3 and 155.4 cm², respectively; the egg weight was 159.1, 154.5 and 192.3 g, respectively; the specific gravity of the eggs was 1.11, 1.11 and 1.12 g/cm³, respectively; the shell thickness was 0.510, 0.504 and 0.555 mm, respectively; the shell weight was 14.79, 14.32 and 18.26 g, respectively; the shell volume was 70.06, 67.82 and 86.41 cm³, respectively; the shell specific gravity was 2.111 3, 2.111 0 and 2.113 5 g/cm³, respectively; and the shell ratio was 9.29, 9.26 and 9.49 g, respectively. The number of pores is calculated as 14 828, 14 502 and 17 152, respectively. Although the formulas used give compatible results, there is a need for formulas that calculate closer to the truth rather than formulas that calculate the egg weight and egg shell weight.

A 2-day-old calf was presented with a bilateral mass in the medial canthus of the upper eyelid. The masses were removed surgically. The morphological diagnosis was a bilateral hamartoma characterised by an abnormal mixture of tissue indigenous to that area including blood vessels, striated muscle bundles, adipose tissue, isolated cartilage and nerve bundles. No recurrence developed in the 6 months following the surgical removal. Overall, although this congenital defect is relatively rare, it should be differentiated from eyelid tumours such as haemangiomas, squamous cell carcinomas, Meibomian gland tumours, dermoid cysts and teratomas in cattle.

This case report describes congenital ichthyosis in a Maltese dog, a condition, which has not previously been reported in this breed. The dog presented with several dry, tightly adhering scales showing a multi-focal appearance. The histology revealed severe orthokeratotic hyperkeratosis and hyperplasia with an irregular granular layer without epidermolysis. Non-epidermolytic ichthyosis (NI) has strong breed predilection in dogs, and its morphological features vary by breed while the microscopic changes are similar. It is likely to be the first reported case of congenital ichthyosis in a Maltese dog showing a different morphological appearance compared to other breeds with a higher prevalence of NI.

Galicia is one of Spain's leading regions regarding agricultural and livestock production. In the light of the COVID-19 crisis, the permeability to the economic shocks of these sectors led to an unprecedented recession, given the heterogeneity of their characteristics, resulting in widespread losses. The main objective of this article is to analyze the impact of COVID-19 in the agricultural and livestock sectors in Galicia and, at the same time, identify the degree of affectation in each of these sectors, determine the impact of the pandemic in each province and study the institutional responses to the COVID-19 crisis. For this purpose, financial analysis of these sectors will be carried out through a sample of 998 companies. The results show a variation in operating income of -16.41% in the agricultural sector and -9.15% in the livestock sector in Galicia, although they are mixed across the different provinces of the region. Despite the articulation of a network of public aids and the adoption of new commercialization strategies, there are sub-sectors with high losses, such as the ornamental plant industry and the subsector dedicated to the production of beef.

Coeliac disease is an autoimmune gluten-sensitive entheropathy. The only available treatment for it is the life-long adherence to a gluten-free diet although these products are often poor in proteins, minerals, and vitamins. The current study was designed to investigate the effect of buckwheat flour incorporation to a gluten-free experimental formulation on the size-related parameters, and microelements and proteins contents. Buckwheat flour affected positively the technological quality of bread, like bread specific volume index and loaf size. Increasing concentration of buckwheat flour (10-40%) in bread affected the proportional enrichment in proteins and microelements, especially in copper and manganese.

This study aimed to develop a bamboo culm flour (BCF) to be used in the formulation of cookies, replacing 15% and 30% of wheat flour (WF). The parameters analysed for bamboo flour and cookies were moisture, ash, protein, fat, fibre and carbohydrates. For the flour, the water absorption index (WAI) and water solubility index (WSI) were also determined. BCF is a good source of protein, with a low lipid content and high fibre content, presenting the potential to be used in several food products. For the cookies produced, hardness, sensory analysis and purchase intent were analysed. In the sensory analysis of acceptability, the samples that showed better acceptance were the control formulation and the 15% BCF cookie; in the same sample, crude fibre increased from 5.92 g (100 g)^-1 to 11.64 g (100 g)^-1 compared to the control, and the intention to purchase the 15% sample was worse than for the control but still good: the majority of tasters said they certainly or maybe would buy. Thus, it is possible to conclude that the use of BCF is considered an excellent option to enrich cookies while keeping them acceptable nutritionally.

The basic chemical composition of the meat of fifteen freshwater and saltwater fish species was studied. Fourier transform-near-infrared (FT-NIR) spectroscopy was applied for determination of the content of fat, protein and dry matter in the fish meat samples. The fish species analysed differed significantly in dry matter, fat, and protein content (P < 0.05). The highest fat percentage was determined in the samples of Cyprinus carpio (17.14 ± 0.53%) and the lowest value was found in the samples of Lophius piscatorius (0.06 ± 0.003%). Thunnus albacares samples had the highest content of proteins (24.26 ± 1.89%), whereas the lowest protein content was observed in Oreochromis niloticus (14.73 ± 0.87%). The results of the measured dry matter varied from the highest content in C. carpio samples (35.73 ± 0.47%) to the lowest content of L. piscatorius samples (15.64 ± 0.43%). Principal component analysis (PCA) extracted three major groups, which differentiate the analysed samples based on their protein, lipid and dry matter content. Partial least squares discriminant analysis (PLSDA) confirmed the use of three variables (protein, fat, dry matter) measured by FT-NIR to separate the observed fish species.

Serum and muscle concentrations of 29 amino acids were determined in Silver fox. Serum concentrations of proline, alanine, tyrosine and aromatic amino acids were significantly higher in males than in females (all P = 0.05). Taurine and glycine concentrations in skeletal muscles were significantly higher in males than in females (P < 0.01). Muscle concentrations of cysteic acid, taurine, aspartate, threonine, serine, glycine, alanine, citruline, valine, leucine, gamma-amino-butyrate, ethanoloamine, lysine and histidine were significantly higher than in serum in both sexes (P < 0.05). In females, the concentrations of glutamate, glutamine, cystathionine, isoleucine, tyrosine, phenylalanine, arginine and amino-adipic acid were significantly higher in muscles than in serum (P < 0.05). Tryptophan concentration was significantly higher in serum from males than in muscles (P = 0.01). The concentration of branched-chain amino acids in skeletal muscles was approximately two times higher than in serum in both groups of foxes (P ≤ 0.01). Similar differences were obtained for aromatic amino acids in females (P = 0.04). The elaborated experimental model may serve for further studies focused on amino acid metabolism regulation in Canide and other monogastric mammals, especially with the use of environmental, dietary, pharmacological and toxicological factors. The elaborated experimental model may be an attractive alternative to replace some experiments on dogs.

The aim of the present study was to compare carcass characteristics and meat quality of fast- (Ross 308), medium- (Hubbard JA757) and slow-growing (ISA Dual) chickens (n = 1 980). When the chickens reached an average live weight of 2 kg, 40 birds (males to females, 1 : 1) of each genotype were randomly selected and slaughtered for carcass analysis. Pectoralis major (PM) muscle samples were taken to determine the physical and chemical parameters of the meat quality. The fast- and medium-growing genotypes had higher (+3.24% and +3.84%, respectively) dressing out percentages than the slow-growing chickens. As expected, the breast percentage significantly decreased in the order of fast growth > medium growth > slow growth. The abdominal fat percentage was the lowest in Ross 308 chickens, but the abdominal fat percentage in JA757 and ISA Dual chickens did not differ. For edible organs, fast- and medium-growing chickens had heavier hearts and livers than slow-growing chickens. In contrast, ISA Dual chickens showed heavier gizzards. Genotype dramatically affected the chemical composition of PM muscle. The ISA Dual chickens exhibited a significantly higher proportion of dry matter and protein and lower ether extract and cholesterol content than Ross 308 chickens, with intermediate values for JA757 chickens. The ISA Dual group had a lower ash content than Ross 308 and JA757 groups. In terms of physical parameters, the ISA Dual chickens had higher lightness and yellowness and lower redness, pH 24, and cooking loss than those of the other genotypes. Concerning all genotypes, the shear force values increased from fast- to slow-growing chickens. In conclusion, this study found a difference between the genotypes. Although the slow-growing chickens showed the lowest dressing out and breast percentages compared with the other genotypes, the breast meat of the slow-growing chickens had more favourable nutritional properties.

In this study, the effect of water temperature, predator's sex, prey density, and the presence of conspecifics on prey consumption of pikeperch (Sander lucioperca) was experimentally tested. In Experiment 1, predators of both sexes [males: total length (TL) = 473 ± 22 mm and body weight (BW) = 1 070 ± 100 g and females: TL = 464 ± 12 mm and BW = 1 060 ± 100 g] were kept in separate tanks and exposed to different densities of prey (Pseudorasbora parva; 3, 6, 12, 24 and 48 prey fishes per tank) under fixed water temperatures of 4.5 °C, 8.5 °C, and 12.5 °C. After 63 days of this experiment, it was found that pikeperch predation was significantly affected by increasing water temperature. The effect of prey density was significant at all tested temperatures. Pikeperch females tended to have the higher prey consumption than males, although that trend was statistically insignificant. Results suggest that increased feeding demands at temperatures above 4.5 °C can lead to predator starvation in conditions of low prey availability. Due to the higher prey consumption, pikeperch females could be more vulnerable to low prey availability during their culture. In Experiment 2, pikeperch were kept at different densities of 1, 2, 4, and 8 individuals per tank supplied with a prey rate of 50 individuals per predator, ensuring ad libitum feeding rate. The average daily prey consumption was significantly higher in the tanks with multiple predators, accounting for 17.6 ± 3.57 prey fishes/day compared to 11.6 ± 2.33 prey fishes/day in the tank with a single predator. These results indicate that pikeperch predation activity and prey consumption can be significantly affected by the water temperature, prey availability, and the presence of conspecifics. The findings contribute to understanding the predatory function, natural feeding request of pikeperch and its potential importance for broodstock culture and broodstock final maturation for a successful spawning season. Also, this information can be used for better management of pikeperch pond aquaculture or bio-melioration process in open water bodies and ecosystems.

: The study evaluates production parameters (height, diameter at breast height, volume) of Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) at mesotrophic sites of the Křtiny Training Forest Enterprise in mature stands. In total, 29 mixed stands were assessed with the registered proportion of Douglas fir at an age of 85 to 136 years. Comparing the 10 largest Douglas firs with the 10 largest spruces or larches higher, and as a rule markedly higher, production potential of introduced Douglas fir was found in all assessed stands. There were also groups of trees where the volume of Douglas fir was twice to 3 times higher than the volume of spruce or larch (see Tabs. 5 to 10). For example, in stand 177B11, the mean volume of 9.12 m³ was recorded in the 10 largest Douglas fir trees but the volume of spruce reached only 3.17 m³ and the volume of larch was 3.70 m³. Differences in mensurational parameters of Douglas fir found on the one hand and of Norway spruce (Picea abies [L.] Karst.) or European larch (Larix decidua Mill.) on the other hand compared by ANOVA tests were statistically highly significant. Annual ring analyses have shown that at present the volume increment of particular Douglas fir trees ranges from 0.12 to 0.16 m³ per year in mature stands (i.e. about 1.5 m³ every 10 years).

The study is a follow-up of the production potential of Douglas fir in mesotrophic sites of the Křtiny Training Forest Enterprise (TFE) (Journal of Forest Science, No. 7, 2008). Production parameters (height, dbh, volume) of Douglas fir are also evaluated, but in acid sites of the Hůrky Training Forest District, Secondary Forestry School in Písek in mature stands. In total, 17 mixed stands with the proportion of Douglas fir aged 88 to 121 years were assessed. Comparing 10 Douglas fir trees with 10 Norway spruce, Scots pine or European larch trees of the largest volume, higher and generally markedly higher production potential of the introduced Douglas fir was always found in all assessed stands. Groups where the volume of Douglas fir trees was two to three times higher than the volume of spruce, pine or larch were not an exception. For example, in stand 22B10, the mean volume of the 10 largest Douglas fir trees was 6.30 m³ but the volume of spruce trees was only 1.93 m³ and the volume of larch trees 2.25 m³. Differences between the mensurational parameters of Douglas fir and spruce (or larch) assessed by the ANOVA test were statistically highly significant. At present (based on annual ring analyses), the volume increment of particular Douglas fir trees ranges at level of 0.06 to 0.10 m³/year (i.e. about 0.6 m³ to 1.0 m³ per 10 years) in mature stands.