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121.
Andrzej Borkowski 《European Journal of Forest Research》2017,136(5-6):893-906
Tomicus minor Hartig (Col., Curculionidae, Scolytinae), occurring on Pinus sylvestris L., is a species which demonstrates high reproductive capability on weakened stands, accelerating the process of forest death. In protected areas, T. minor is regarded as a sensitive bioindicator that reacts to decline in the health and vitality of forests. Although there have been many publications concerning T. minor, no precise method has yet been given for estimating its population so as to enable the monitoring of forest vitality and assessment of the role played by T. minor in the forest ecosystem. The aim of the present work is to develop a statistical method for estimating populations of T. minor, requiring minimum work and interference with the forest ecosystem and permitting the computation of estimation errors. Research was carried out in the years 1992–2011 in pine stands aged over 80 years, growing in a variety of habitats and situated at varying distances from sawmill timber yards. Attack density of T. minor was measured on trap logs made from uninfested living trees. The population of T. minor on the trap logs was described using a multiple linear regression model with two explanatory variables. Among the features investigated, the T. minor population was found to depend significantly on the number of egg galleries on the fifth metre of the trap log counted from the thinner end (p < 0.001) and on the diameter of the trap log in bark at the thinner end (p < 0.05). The model explains approximately 85% (R 2 = 0.8564) of the variation in the total number of T. minor egg galleries on the trap logs. The numbering of units beginning from the thinner end of the log enabled increased precision in determining the model parameter resulting from the concentration of egg galleries on certain units of the log. In all validated plots, the mean real and model values for the number of T. minor egg galleries on the trap logs are similar (p > 0.5), confirming the high accuracy of the developed model. 相似文献
122.
Piotr Lijewski Jerzy Merkisz Paweł Fuć Andrzej Ziółkowski Łukasz Rymaniak Władysław Kusiak 《European Journal of Forest Research》2017,136(1):153-160
The paper focuses on the determination of fuel consumption (CO2 emission) and exhaust emissions such as CO, HC, NOx, and PM in the process of timber extraction and transport. A complex assessment of fuel consumption and exhaust emissions was performed for the entire, fully mechanized supply chain including, tree felling, delimbing, and bucking with a harvester, timber extraction with a forwarder and transport with a truck. The performed investigations determined unit exhaust emissions (referred to 1 m3 of timber) for the entire technological process and its individual stages. The investigations of the exhaust emissions and fuel consumption were performed under actual conditions of typical forest operations and transport. State-of-the-art portable emissions measurement system equipment was used for the measurements. The fuel consumption was determined through the carbon balance method. The investigations were performed for the process of extraction and transport of pulpwood. The measurements were performed on location in the town of B?bnik?t near Poznań, in a pinewood forest, typical of this part of Europe. The analysis includes the transport of timber to the lumberyard on a distance of 31.4 km. The total fuel consumption for the entire mechanized supply chain was 2.10 dm3/m3. The total exhaust emissions, however, amounted to: CO—8.91 g/m3, HC—1.19 g/m3, NOx—45.32 g/m3, PM—4.04 g/m3. 相似文献
123.
An attempt to render oocytes and embryos free from the porcine circovirus type 2 after experimental in vitro exposure
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Andrzej Bielanski Renée Larochelle Ronald Magar 《Canadian journal of veterinary research》2004,68(3):222-225
The purpose of this study was to investigate the possibility of rendering oocytes and embryos free of porcine circovirus type 2 (PCV2). Groups of cumulus oocytes complexes, cumulus free oocytes, and embryos 3 to 5 d post breeding were exposed to PCV2 (10(5) TCID50/mL) prior to disinfection by washing and different combinations of enzymatic treatments. The study suggests that under the in vitro conditions used, standard washing procedures with, or without, trypsin or incorporating pronase or hyaluronidase and DNase/RNase in the treatment was not effective in rendering oocytes and embryos free from PCV2 nucleic acid. Since the virus is noncytopathic in cell culture and for embryonic cells, it appears that there is a possibility of introducing viral contamination through oocytes collected from infected pigs into the in vitro fertilization system with subsequent potential of producing in vitro fertilized embryos associated with PCV2. 相似文献
124.
125.
Andrzej Borkowski 《Journal of Forest Research》2007,12(5):358-364
Methods of spatial distribution of fallen shoots, pruned by pine shoot beetles, and estimation of efficiency of methods based
on collection of fallen shoots and used in forecasting of the occurrence of these insects, are presented in this paper. The
fallen shoots were distributed in clusters. The distribution was statistically different from random. Relative errors in estimation
of shoot-fall density were the smallest in study transects. Early and late autumn and the following spring, after the snow
melt, are the optimum seasons for collecting fallen shoots. 相似文献
126.
Transitional cell carcinoma of the urinary bladder in a 12‐year‐old Belgian Warmblood gelding
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A 12‐year‐old Belgian Warmblood gelding was examined for haematuria and dysuria of 24 h duration. Cystoscopy revealed an intraluminal multinodular soft tissue mass originating from the dorsal bladder neck. Histopathological examination of biopsies identified transitional cell carcinoma. The bladder mass was surgically debulked via a temporary perineal urethrotomy. The horse commenced treatment with oral piroxicam. Follow‐up examination 18 months post operatively revealed no evidence of tumour recurrence. Neoplasia of the equine bladder is uncommon and this case describes the successful short‐term outcome of treatment of a transitional cell carcinoma by surgical debulking and oral piroxicam. 相似文献
127.
Maciej Rożyński Andrzej Kapusta Krystyna Demska-Zakęś Marek Hopko Agnieszka Sikora Zdzisław Zakęś 《Fish physiology and biochemistry》2017,43(4):999-1010
The aim of this work was to determine the impact of surgically implanted telemetry transmitters (TTs) on the growth, survival, hematological and biochemical indexes, and wound healing in juvenile pikeperch (Sander lucioperca) (body weight 60–90 g). Two incision suturing methods were used—silk sutures (experiment I—group ST) or tissue adhesive (experiment II—group GT). After tagging, the fish were held in a recirculating system for 35 days. No statistically significant differences were noted in the growth or condition indexes analyzed among the fish tagged with TT compared with those from the control groups (untagged). Substantial individual variability was noted, however, in the parameters examined in both the control and tagged groups. Among the hematological indexes, statistically significant differences were only noted in experiment I. Lower values of mean corpuscular volume and mean corpuscular hemoglobin were noted in group ST. Among the biochemical parameters, creatinine was statistically significantly threefold lower, magnesium and alkaline phosphatase (ALP) levels were lower, and ammonia levels were higher in group ST than in the control group. In experiment II, significant differences were only noted for ALP. Tissue adhesive was the superior and more effective method for closing the incision after TT implantation in juvenile pikeperch. This type of suturing facilitated faster healing, and it had less of an impact on juvenile pikeperch welfare. 相似文献
128.
129.
Influence of water salinity on the survival of embryos and growth of the sichel larvae Pelecus cultratus (L.) under controlled conditions
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Roman Kujawa Mariusz Lach Przemysław Pol Marcin Ptaszkowski Andrzej Mamcarz Joanna Nowosad Grażyna Furgała‐Selezniow Dariusz Kucharczyk 《Aquaculture Research》2017,48(3):1302-1314
The purpose of this study was to analyse the influence of water salinity on the incubation of eggs and growth of the larvae of sichel Pelecus cultratus (L.) under controlled conditions. The following water salinity was considered: 3, 6, 9, 12, 15 and 0 ppt for the control. The eggs incubation time depended on the water salinity, lasting from 56.3°D [9 ppt] to 107.7°D [0 ppt]. The higher water salinity, shorter the incubation time. The highest survivability of larvae was obtained in water of the salinity equal 3 ppt and in freshwater, where respectively 87% and 84% of the larvae survived. No hatched larvae were obtained in water of the salinity of 12 and 15 ppt, as all embryos died during the experiment. Larvae were reared up for 21 days. The final body weight, depending on the water salinity, reached from 43.5 mg [9 ppt] to 74.6 mg [3 ppt], at the respective body lengths of 19.3 mm and 23.2 mm. The highest body gains and lengths of larvae were observed in water of the salinity of 3 ppt. The lowest survivability of sichel larvae occurred in water of the salinity 9 ppt, where it was only 53.2%. The survivability of larvae in freshwater and water of the salinity of 3 ppt was quite similar: 96.2% and 95.6% respectively. Water salinity degree of 12 and 15 ppt appeared to be lethal for both embryos and larvae of the sichel. 相似文献
130.
Patrycja Schulz Joanna Pajdak‐Czaus Stanisaw Robak Jarosaw Dastych Andrzej K. Siwicki 《Journal of fish diseases》2019,42(8):1151-1160
Recently, a rapid increase in the resistance of pathogenic bacteria to antibiotics and chemotherapeutics admitted for use in aquaculture has been observed. This happens especially often in intensive breeding. The use of drugs in closed circuits is problematic because it can damage biological filters. Therefore, in recent years, there has been a growing interest in natural methods of combating pathogens. These include bacteriophages. The aim of the study was to determine the safety of the new BAFADOR® bacteriophage‐based preparation, its effect on selected immunological parameters and the effectiveness of prophylactic and therapeutic use after experimental infections with pathogenic bacteria Aeromonas hydrophila and Pseudomonas fluorescens. The use of BAFADOR® increased the activity of lysozyme, total protein level and immunoglobulin level. The level of ceruloplasmin in the rainbow trout serum remained unchanged regardless of the route of administration of the preparation. Potential killing activity and metabolic activity of spleen phagocytes and proliferation of pronephros lymphocytes were higher compared to the control group. Both therapeutic and prophylactic application of the preparation after mixed experimental infection of A. hydrophila and P. fluorescens limited the mortality of rainbow trout. 相似文献