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Results 2881 to 2910 of 4598:

Study of briquette properties at their long-time storageOriginal Paper

M. Broľek

J. For. Sci., 2013, 59(3):101-106 | DOI: 10.17221/27/2012-JFS

The paper presents the results of laboratory tests aimed at the study of storage place, storage manner and storage time in relation to mechanical properties of briquettes made from spruce shavings. A BrikStar 50 briquetting press with a pressure chamber 65 mm in diameter of the Briklis firm was used for the briquette production. All briquettes were made at the constant adjustment of all parameters of the briquetting press. The briquette properties were evaluated by determination of their density and rupture force. Moreover, mechanical durability, gross calorific value, total mois­ture and ash content were determined. It follows from the results of tests that at briquette storage in a well closed plastic bag neither place nor storage time influenced significantly their life time. At briquette storage in a net plastic bag various intensive damage to briquettes occurred, mainly depending on their storage place and storage time.

Rural and environmental concern - focus on the Czech Republic

Petr Kment, Lucie Kocmánková

Agric. Econ. - Czech, 2012, 58(4):191-199 | DOI: 10.17221/37/2010-AGRICECON

An increasing number of works on the rural-environmental connection can be found at present. However, their overview and classification are needed - this is the guiding idea of this paper. We distinguish three approaches to the rural-environmental connection and label them scientific approach, environmentalist approach, and development approach. In the paper, theories of environmental concern (post-materialism, paradigm shift, and ecological modernisation) are discussed at first and then a classification of works is proposed.

Anastomosis grouping of Rhizoctonia solani and binucleate Rhizoctonia spp. isolated from pepper in Erzincan, TurkeyOriginal Paper

Serdar Tuncer, Cafer Eken

Plant Protect. Sci., 2013, 49(3):127-131 | DOI: 10.17221/77/2012-PPS

Ninety eight isolates of Rhizoctonia spp. were obtained from roots of pepper (Capsicum annuum L.) grown in Erzincan, Turkey during the period 2007-2008. The most prevalent multinucleate anastomosis groups (AG) were AG-4 (85.2%), followed by AG-2 type 1 (7.4%), AG-6 (5.0%), and AG-3 (2.5%). The population of binucleate Rhizoctonia spp. comprised AG-A (82.4%), AG-K (11.8%), and AG-G (5.9%). Rhizoctonia solani AG-3 and AG-6, as well as binucleate Rhizoctonia spp. AG-G and AG-K on pepper (C. annuum) were firstly determined in this study. During both in vitro and in vivo pathogenicity experiments differences in virulence level between R. solani and binucleate Rhizoctonia spp. isolates were observed. Isolates of R. solani AG-2 type 1 and AG-4 were the most virulent, binucleate Rhizoctonia spp. isolates of AG-A were less virulent, whereas binucleate Rhizoctonia spp. isolates of AG-G and AG-K were non-pathogenic.

Investigations on the postnatal development of the foliate papillae using light and scanning electron microscopy in the porcupine (Hystrix cristata)Original Paper

S. Yilmaz, A. Aydin, G. Dinc, B. Toprak, M. Karan

Vet Med - Czech, 2013, 58(6):318-321 | DOI: 10.17221/6868-VETMED

In this study SEM and light microscopy were used to investigate the structure of the foliate papillae in the porcupine. The foliate papillae consisted of about 10 or 11 clefts. The length of the foliate papillae averaged 2.79 mm and its width averaged 863 µm. Taste buds were located intraepithelial in the basal half of the papilla grooves (sulcus papillae). Every wall on each fold harboured from five to nine taste buds. There were two different cell types of taste buds: one stained light (epitheliocytus sensorius gustatorius), and the other dark (epitheliocytus sustentans). The length and width of the taste buds averaged 190.5 µm and 86 µm, respectively. The ratio of the length to the width of taste buds was 2.21. The average depth of the papilla groves was 1763 µm and its epithelial thickness was 235.5 µm. In scanning electron microscopy, the thickness of the epithelial cell borders was apparent at higher magnifications and there micro-ridges and micro-pits were apparent on the surfaces of these cells.

Improving nutritional quality of wheat through soil and foliar zinc applicationOriginal Paper

K. Bharti, N. Pandey, D. Shankhdhar, P.C. Srivastava, S.C. Shankhdhar

Plant Soil Environ., 2013, 59(8):348-352 | DOI: 10.17221/158/2013-PSE

A field study was conducted to ascertain the effect of three zinc (Zn) levels: 0, 20 kg ZnSO4/ha and 20 kg ZnSO4/ha + foliar spray of 0.5% ZnSO4, on wheat grain Zn content and factors contributing to or hindering in its bioavailability. Increasing Zn levels were established as serviceable in improving the nutritional status of genotypes. Soil application + foliar spray proved to be paramount for all the traits leading to an 80% increase in grain Zn content, 61.3% in methionine content and a decrease of 23.2% in phytic acid as an average of all genotypes and both years. The genotype UP 2382 was found more suited to Zn fertilization in allocating Zn and maintaining a lower phytate to Zn molar ratio.

Disseminated intravascular coagulation in dogs with gastric dilatation-volvulus syndromeOriginal Paper

I. Uhrikova, K. Machackova, L. Rauserova-Lexmaulova, K. Rehakova, J. Doubek

Vet Med - Czech, 2013, 58(11):587-590 | DOI: 10.17221/7141-VETMED

Gastric dilatation and volvulus syndrome is associated with changes in haemostatic profiles. The aims of this study were to compare selected haemostatic and fibrinolytic parameters between healthy dogs and dogs with gastric dilatation and volvulus syndrome, estimate the incidence of disseminated intravascular coagulation (DIC), and determine the most sensitive test for detection of DIC in these patients. Blood was collected from 22 dogs with gastric dilatation and volvulus syndrome, and nine healthy control dogs. Platelet counts, prothrombin time, activated partial thromboplastin time, fibrinogen concentrations and fibrin/fibrinogen degradation products were measured in all control dogs and patients with gastric dilatation and volvulus syndrome, before and after surgery. Significant differences between control dogs and patients were seen in activated partial thromboplastin time and fibrin/fibrinogen degradation products before surgery and all measured parameters after surgery. The incidence of DIC was 59%. The most sensitive tests for detection of DIC before surgery were those for activated partial thromboplastin time and fibrin/fibrinogen degradation products.

The effect of light availability on leaf area index, biomass production and plant species composition of park grasslands in WarsawOriginal Paper

P. D±browski, B. Pawlu¶kiewicz, H.M. Kalaji, A.H. Baczewska

Plant Soil Environ., 2013, 59(12):543-548 | DOI: 10.17221/140/2013-PSE

How light conditions affect development of park grasslands is a question that has not been satisfactory addressed. The aim of this study was therefore determination of the level to which unfavorable light conditions influence grassy parks area and relationships between parameters which determine state of turf grasses. Researches were conducted in two parks in Warsaw, in various light conditions and included measurement of: leaf density, sward height, leaf area index (LAI), and botanical composition of the communities. The leaf density of shaded areas did not exceed 70%. LAI value varied from 0.5 to 0.9-fold lower than in the areas in half-shade and in sun. The participation of basic lawn species at Skaryszewski Park was higher under shade, while at Łazienki Królewskie was higher in full-sunlight areas. The state of tested grassy areas in limited solar radiation does not satisfy the requirements of recreational and representational functions. The development processes of vegetation coverage were inhibited at the sites of lower solar radiation. LAI was influenced by both leaf coverage and sward height. Agrostis stolonifera and Poa trivialis may be recommended to create grass areas under limited solar radiation.

Fecundity and development rate of the bird cherry-oat aphid, Rhopalosiphum padi (L) (Hom.: Aphididae) on six wheat cultivars

Sedigheh Taheri, Jabraeil Razmjou, Nowzar Rastegari

Plant Protect. Sci., 2010, 46(2):72-78 | DOI: 10.17221/10/2009-PPS

Rhopalosiphum padi is a polyphagous species with a nearly worldwide distribution. Biological parameters of this aphid on six commonly grown wheat cultivars in the Fars province including Chamran, Darab2, Shiraz, Ghods, Marvdasht and Niknezhad were investigated at the two-leaf stage of wheat. The experiments were carried out at 24 ± 5°C, 65 ± 5% R.H. and a photoperiod of 14:10 h (L:D) in a greenhouse. The number of nymphs per female of R. padi was 62.05, 55.84, 49.89, 47.63, 42.76 and 40.65 (nymphs/female) on Niknezhad, Shiraz, Ghods, Marvdasht, Chamran, and Darab2, respectively. Also, the highest and the lowest rm values of this aphid were obtained on Niknezhad (0.381 per day) and Darab2 (0.328 per day), respectively. In addition, other population growth indices were estimated. In general, a high level of antibiosis in Darab2 compared with the other tested cultivars may decrease the population density of R. padi on wheat and also cause a suppression of cereal viruses (e.g. BYDV) and reduce the pesticide application to wheat fields of Iran.

Enhancing unsaturated fatty acids in ewe's milk by feeding rapeseed or linseed oil

A. Cieslak, J. Kowalczyk, M. Czauderna, A. Potkanski, M. Szumacher-Strabel

Czech J. Anim. Sci., 2010, 55(11):496-504 | DOI: 10.17221/874-CJAS

The aim of our research was to evaluate whether rapeseed and linseed oils used as feed additives to ewe's diets allow to achieve the higher secretion of unsaturated fatty acids into milk with extended emphasis on the conjugated linoleic acid concentration. Two experiments were carried out on 6 lactating ewes in two independent 3 × 3 Latin square designs. In each feeding cycle the animals were subjected to one of the treatments: (1) without oil supplementation, (2) with 3.5% of rapeseed oil (RS) or linseed oil (LS), (3) with 7.0% of rapeseed oil or linseed oil. Feeding diets rich in mono- and polyunsaturated fatty acids to lactating ewes under our experimental conditions resulted in demanded changes in milk fatty acid content without causing milk fat depression or modification of other milk constituents. Milk fat was improved in unsaturated fatty acids including C18:2 c9 t11 CLA isomer without changing the milk fat concentration. The C18:2 c9 t11 concentration increased from 0.03 (FAME, %) in the control group to 0.21 and 0.12 (FAME, %) in groups receiving 3.5 and 7% RS, respectively. The diet with 7% LS also elevated the C18:2 c9 t11 level in milk from 0.04 (FAME, %) in the control group to 0.11 (FAME, %). Hence a conclusion is drawn that plant oils may be an important source of monoenic and also polyenic fatty acids in milk, however, our research and analysis of literature data indicate that results are strictly dietary and supplement-dependent.

Germination of acorns and development of oak seedlings (Quercus robur L.) following flooding

C. Kühne, N. Bartsch

J. For. Sci., 2007, 53(9):391-399 | DOI: 10.17221/2144-JFS

Seeds and seedlings of Quercus robur, a characteristic tree species of the hardwood floodplain forests along the Rhine River, demonstrated high resistance to complete inundation under controlled conditions. In both experimental trials no significant difference between the different flooding periods (8, 10, and 12 weeks) could be established either for shoot emergence or for the measured morphological growth parameters. Flooding delayed the germination of submerged acorns till the end of inundation. However, seeds of the flooding treatments had significantly higher germination rates than the non-flooded acorns of the control. Likewise, dry weights of seedlings from the flooded seeds were significantly higher than those of seedlings from seeds not flooded. Aboveground growth in the 24-week growth period following flooding was reduced in favour of root development in either trial of the experiment. Restricted leaf development and reduced shoot elongation stalled the growth of young oaks in the seedling trial. The results confirm knowledge from earlier experiments about the flood tolerance of Quercus robur seed and seedlings. They also serve to explain why oak seedlings are widespread on the Rhine floodplain after mast years, but gradually disappear in successive years.

The influence of orally administered short chain fatty acids on intestinal histopathological changes and intensity of Trichinella spiralis infection in mice

D. Mista, J. Piekarska, M. Houszka, W. Zawadzki, M. Gorczykowski

Vet Med - Czech, 2010, 55(6):264-274 | DOI: 10.17221/2992-VETMED

The influence of short chain fatty acids (SCFA) on histopathological changes in the small intestine and the intensity of invasion of T. spiralis in mice were investigated in this study. The animals were infected with doses of 500 and 250 T. spiralis larvae per mouse. A SCFA solution containing acetic, propionic and butyric acid (30 : 15 : 20mM) was administered orally to the mice starting from the 5th day before infection to the 20th day after infection (day). Fragments of the jejunum collected during dissection on the 7th and 10th day were used to prepare specimens to assess the histopathological changes. In the infected animals, the intestinal trichinellae were counted on the 7th and 10th day, while on the 42nd day the muscle larvae number were determined. The strongest host reaction in the intestine was observed on the 7th day at a dose of T. spiralis 500 larvae, and on the 10th day at a dose of 250 larvae. Numerous inflammatory infiltrations, strong shortening of the intestinal villi, extension of the intestinal crypts, and the lowest ratio of the villi length to the intestinal crypts depth were observed. The ratio was 1.3 ± 0.3 on the 7th day at a dose of 500 larvae, and on the 10th day, at dose of 250 larvae the ratio reached 1.5 ± 0.5. Both values differed significantly from the control group: 3.3 ± 0.5 (P < 0.01). Administration of SCFA to the animals infected with T. spiralis caused remission of local histopathological changes resulting from the presence of the parasite in the small intestine after the mentioned periods. This manifested as limited villi shortening and reduced deepening of intestinal crypts. At the higher infectious dose, in animals receiving the acid solution, on the 7th day the intestinal villi were considerably longer (356 µm ± 35) than in the group infected with T. spiralis but not treated with the acids (279 µm ± 57; P < 0.01). At a lower dose of parasites, on the 10th day these values were 339 µm ± 88 and 306 µm ± 47 respectively and the observed differences were not statistically significant. The solution of SCFA also caused a decrease in the numbers of mature parasites in the intestine and the muscle larvae at a dose of 500 larvae/mouse. In animals receiving the SCFA, 24 050 ± 10 415 larvae were observed in muscles, while in the infected mice, which did not receive the acids, 32 875 ± 16 762 larvae were detected (P < 0.05). An increase in the intensity of infection accelerated the rate of host reaction to the presence of T. spiralis in the intestines (self-cure). To summarize, the administered solution of short chain fatty acids alleviated the formation of histopathological changes in the intestine in response to the parasite's presence, and lowered the intensity of T. spiralis invasion after infection with a higher dose of larvae.

Selenium and α-tocopherol content in eggs produced by hens that were fed diets supplemented with selenomethionine, sodium selenite and vitamin E

M. Skřivan, I. Bubancová, M. Marounek, G. Dlouhá

Czech J. Anim. Sci., 2010, 55(9):388-397 | DOI: 10.17221/92/2010-CJAS

The effect of supplementing dietary selenium (Se) and vitamin E was investigated in 330 24-week-old laying hens. The hens were fed a basal diet containing Se and α-tocopherol at 0.11 and 26 mg/kg, respectively, or a diet supplemented with Se at 0.3 mg/kg and vitamin E between 0 and 625 mg/kg. Se was supplied as Se-methionine or sodium selenite. The eggs were collected for analysis during the third, seventh and eleventh weeks of the experiment. Supplementation of either form of Se significantly increased the Se concentration in egg yolks and whites, with a more pronounced effect caused by Se-methionine. The egg yolk α-tocopherol concentration paralleled the dietary α-tocopherol concentration. At a high dietary α-tocopherol concentration (632 mg/kg), the retinol content in egg yolks from hens fed Se-methionine increased significantly. Supplementation of Se-methionine significantly increased the α-tocopherol content in the eggs in the third and seventh weeks of the experiment. A moderate decrease in yolk cholesterol was observed in hens fed Se-methionine and α-tocopherol at 119 mg/kg. The concentration of products from lipid peroxidation (thiobarbituric acid-reactive substances, TBARS) in egg yolks increased marginally during the refrigerated storage of the eggs for 2 weeks. The effect of dietary vitamin E on TBARS formation was generally small, although a more significant effect was observed at the highest dose tested.

Response of larval and juvenile rudd Scardinius erythrophthalmus (L.) to different diets under controlled conditions 331

J. Wolnicki, J. Sikorska, R. Kamiński

Czech J. Anim. Sci., 2009, 54(7):331-337 | DOI: 10.17221/1723-CJAS

The growth and survival of rudd Scardinius erythrophthalmus (L.) were evaluated in a laboratory at 25°C. In 20-day Experiment 1, first-feeding larvae at the age of 4 days post-hatch (initially: TL = 5.7 mm, BW = 0.9 mg) were fed live Artemia nauplii or commercial dry feed (Aller Futura Larvae, AFL) or combinations of both. Even the longest period of initial feeding of nauplii (6 days) was insufficient to obtain satisfactory larval growth after weaning to AFL (TL = 12.4 mm and BW = 17.7 mg vs. TL = 18.9 mm and BW = 68.5 mg for the nauplii-fed fish, significant differences). Nauplii-fed older larvae (24 days post-hatch) were then used in Experiment 2, in which they were fed AFL or Ewos AgloNorse (EAN) dry feeds for 40 days. The EAN diet proved to be significantly (P ≤ 0.05) superior to AFL regarding the final fish growth (TL = 36.5 mm and BW = 506.8 mg vs. TL = 33.4 mm and BW = 392.0 mg ), final survival rates (97.6% vs. 100%) and the incidence of spinal deformities (0% vs. 13.5%).

Sperm motility and monthly variations of semen characteristics in Perca fluviatilis (Teleostei: Percidae)

S.M.H. Alavi, M. Rodina, A. Hatef, V. Stejskal, T. Policar, J. Hamáčková, O. Linhart

Czech J. Anim. Sci., 2010, 55(4):174-182 | DOI: 10.17221/118/2009-CJAS

Dynamics of sperm motility (sperm velocity, percentage of motility and flagellar beat frequency) and monthly variations of semen characteristics (semen volume and osmolality and sperm concentration and motility) were studied in Perca fluviatilis. This study showed that sperm velocity, percentage of motility and flagellar beat frequency significantly and rapidly decreased after the activation of sperm motility. Twelve spermiating males were randomly selected and electronically tagged to study monthly variations of semen characteristics. The semen was collected 4 times (29th November 2005, 10th January 2006, 21st February 2006, and 7th April 2006). Semen volume did not change significantly from November to February, but it significantly increased in April. Sperm concentration was higher in November and January than in February and April. The highest and the lowest osmolality of semen was observed in January and April while it decreased in February and April. At 15 s post activation, the lowest percentage of motile spermatozoa was observed in November. The semen samples collected in April showed the lowest motility of spermatozoa (24.3%) at 30 s post activation. But the percentage of motile spermatozoa collected from November to February showed more than 65% motility at 30 s post activation. At the end of motility period (60 s post activation), no motile spermatozoa were observed in April, and the highest motility was in November. Sperm velocity did not show any significant differences at 15 s post activation. The lowest sperm velocity was observed in April at 30 s post activation.

Analysis of clinical and perioperative findings in 576 horses subjected to surgical treatment of colic

J. Mezerova, Z. Zert, R. Kabes, L. Ottova

Vet Med - Czech, 2008, 53(1):29-42 | DOI: 10.17221/1933-VETMED

Colic was treated surgically in 576 horses (545 individuals). Twenty-seven horses were subjected to surgery twice and two horses three times during the period of this study. A total of 371 horses (64.4%) were discharged from the hospital, 205 animals (35.6%) died or were euthanised; 16 of them died during anaesthesia, 102 horses were subjected to euthanasia during surgery, 24 patients did not recover from anaesthesia after surgery completion, and 63 horses did not survive the postoperative period. Ileus of the small intestine was diagnosed in 267 cases (46.4%), affection of the large colon in 239 cases (41.5%), lesion of the small colon in 22 cases (3.8%), lesion of the caecum in 19 cases (3.3%), and affection of stomach and rectum in four and one cases, respectively. In 14 animals (2.4%), lesions were located at two different sites of the gastrointestinal tract. In four horses, the cause of colic was located outside the gastrointestinal tract. Three animals were affected by diffuse peritonitis. No gastrointestinal lesion could be identified during surgery in three horses with recurrent colic. The most common causes of small intestine ileus included incarceration in inguinal hernia (50 of 267 horses, 18.7%), hernia of the omental foramen (31 of 267 horses, 11.6%), anterior enteritis (19 of 267 horses, 7.1%), mesenterial volvulus (18 of 267 horses, 6.7%), and ileal impaction (18 of 267 horses, 6.7%). The most common caecal disorder was acute constipation/dysfunction (5 of 19 horses, 26.3%). Frequent causes of the large colon colic were torsion (63 of 239 horses, 26.4%), left dorsal displacement (36 of 239 horses, 15.1%), and right dorsal displacement (23 of 239 horses, 9.6%). The small colon was most often affected by focal obstruction/constipation (9 out of 22 horses, 40.9%). Surgical treatment of colic of the small intestine, caecum, large colon, and small colon was successful in 59.6%, 36.8%, 73.3%, and 63.6% of the cases, respectively.

Soil degradation: a problem threatening the sustainable development of agriculture in Northeast China

X.B. Liu, X.Y. Zhang, Y.X. Wang, Y.Y. Sui, S.L. Zhang, S.J. Herbert, G. Ding

Plant Soil Environ., 2010, 56(2):87-97 | DOI: 10.17221/155/2009-PSE

Soil degradation that results from erosion, losses of organic matter and nutrients, or soil compaction are of great concern in every agricultural region of the world. The control of soil erosion and loss of organic matter has been proposed as critical to agricultural and environmental sustainability of Northeast China. This region is bread basket of China where the fertile and productive soils, Mollisols (also called Black soils), are primarily distributed. In this paper, we introduce the importance of Northeast China's grain production to China, and describe the changes of sown acreage and grain production in past decades. This paper also summarizes the distribution, area and intensity of water erosion, changes in the number of gullies and gully density, thickness of top soil layer, soil organic matter content, bulk density, field water holding capacity, and infiltration rates; the number of soil microorganism and main enzyme activities from soil erosion in the region are also summarized. The moderately and severely water-eroded area accounted for 31.4% and 7.9% of the total, and annual declining rate is 1.8%. Erosion rate is 1.24-2.41 mm/year, and soil loss in 1°, 5° and 15° sloping farmlands is 3 t/ha/year, 78 t/ha/year and 220.5 t/ha/year, respectively. SOC content of uncultivated soil was nearly twice that of soil with a 50-year cultivation history, and the average annual declining rate of soil organic matter was 0.5%. Proper adoption of crop rotation can increase or maintain the quantity and quality of soil organic matter, and improve soil chemical and physical properties. Proposed strategies for erosion control, in particular how tillage management, terraces and strip cultivation, or soil amendments contribute to maintain or restore the productivity of severely eroded farmland, are discussed in the context of agricultural sustainability with an emphasis on the Chinese Mollisols.

Microbial biomass dynamics after addition of EDTA into heavy metal contaminated soils

G. Mühlbachová

Plant Soil Environ., 2009, 55(12):544-550 | DOI: 10.17221/124/2009-PSE

An incubation experiment with addition of EDTA and alfalfa into soils contaminated with heavy metal over 200 years was carried out in order to evaluate the EDTA effects on microbial properties. Alfalfa was added to soils together with EDTA to examine its abilities to improve microbial activities affected by EDTA. The obtained results showed that the addition of EDTA led to a significant decrease of microbial biomass C during the first 24 days of incubation. At the end of the experiment the microbial biomass C significantly increased quite close to the original level. The EDTA amendment caused, probably due to the toxic effects, a significant increase in respiratory activities and of the metabolic quotient qCO2. An addition of alfalfa significantly improved the microbial biomass C contents in arable soils treated together with EDTA. Both, respiratory activities and qCO2 significantly increased after the soil treatment with EDTA together with alfalfa. EDTA alone decreased the microbial biomass, alfalfa alone as organic substrate was mineralised and utilised by soil microorganisms for their metabolism.

Antioxidant enzymes changes in response to drought stress in ten cultivars of oilseed rape (Brassica napus L.)Original Paper

Tayebeh ABEDI, Hassan PAKNIYAT

Czech J. Genet. Plant Breed., 2010, 46(1):27-34 | DOI: 10.17221/67/2009-CJGPB

The study was undertaken to identify the responses of antioxidant enzyme activities and their isozyme patterns in seedlings of 10 oilseed rape (Brassica napus L.) cultivars under drought stress conditions. Plants were grown under three irrigation regimes (FC; field capacity, 60% FC and 30% FC) in a greenhouse. Drought stress preferentially enhanced the activities of superoxide dismutase (SOD) and guaiacol peroxidase (POD) whereas it decreased catalase (CAT) activity. Licord with the highest level of enzyme activity under both optimum and limited irrigation regimes is reported as the most tolerant cultivar. Whereas Hyola 308 and Okapy, having the lowest enzymes activities, are mentioned as cultivars sensitive to drought stress. The native polyacrylamide gel electrophoresis (PAGE) analysis detected eight SOD isozymes. Oilseed rape leaves contained three isoforms of Mn-SOD and five isoforms of Cu/Zn-SOD. The expression of Mn-SOD was preferentially enhanced by drought stress. Five POD isoforms were detected in oilseed rape leaves. The intensities of POD-4 and -5 were enhanced under drought stress. According to the results, the appearance of new isozyme bands under drought stress conditions may be used as a biochemical marker to differentiate drought tolerant cultivars under drought stress.

Effect of dietary supplementation of some antioxidants on growth performance, carcass composition and breast meat characteristics in quails reared under heat stress

H. Imik, M. Aydemir Atasever, M. Koc, M. Atasever, K. Ozturan

Czech J. Anim. Sci., 2010, 55(5):209-220 | DOI: 10.17221/147/2009-CJAS

This research investigates the effects of adding vitamin E, vitamin C, vitamin E+C, and alpha lipoic acid to feed rations for Japanese quails (Coturnix coturnix japonica) exposed to heat stress. The aspects studied were growth performance, carcass composition and breast meat characteristics. Five groups of quails, containing 50 birds each (250 Japanese quails: 150 female and 100 male) were used. The 21-days-old birds were fed for a period of 21 days, and they were kept in a controlled environment with a temperature of 34˚C between 08:00 and 17:00 and a temperature of 24˚C for the remaining part of the day. The five groups under study included: a control group without any additive (BS), a group fed diets with vitamin E (BSE), with vitamin C (BSC), with vitamin E+C (BSEC) and with lipoic acid (BSLA). The supplement additions to the diets did not affect the growth performance and carcass composition of the birds. The TBA (malonaldehyde) value of the BS group was significantly higher (P < 0.001) than in the other groups. L*, a*, and b* values in muscle samples, superficialis pectoralis muscle (SPM) and deep pectoralis muscle (DPM), were determined. In the samples from the SPM, the L* value of the BS group was higher than in the BSC group; the a* value of the BSE group was higher than in the BS group; and the b* value of the BSC group was higher than in the BS group (P < 0.05). In the samples from the DPM, the L* value of the BS group was higher than in the BSEC group (P < 0.05); the a* values of the BSE and BSEC groups were higher than in the BS group (P < 0.05); and the b* values of the BSC, BSEC and BSLA groups were higher than in the BS group (P < 0.01). In the microbiological analysis of meat, total aerobic mesophilic bacterial counts of the BS and BSE groups were higher than the counts in the BSC, BSEC, and BSLA groups (P < 0.01); coliform bacterial counts were higher in the BSE group than in the BSC group (P < 0.05); and lactic acid was higher in the BSE and BSEC groups than in the BSC and BSLA groups (P < 0.01). In conclusion, the supplemented antioxidants did not exhibit any significant effect on growth performance, but they significantly decreased lipid oxidation in the meat.

Evaluating the shelterwood harvesting system after 25 years in a beech Fagus orientalis Lipsky) forest in Iran

M. R. Pourmajidian, N. E. Malakshah, A. Fallah, A. Parsakhoo

J. For. Sci., 2009, 55(6):270-278 | DOI: 10.17221/77/2008-JFS

Beech (Fagus orientalis Lipsky) is the most industrial commercial tree species among more than 80 broadleaved trees and shrubs in Hyrcanian forests. In this study some of the silvicultural properties of beech were studied under a shelterwood cutting system in a regeneration unit of 25 years old stand in Sangdeh forests of Iran. Tree height, diameter, canopy cover, variety of species, frequency at different stages of growth (seedling, sapling, thicket and pole) and tree density at juvenile phase were recorded in 431 circular 1,000 m2 sample plots before and after shelterwood cutting. Results indicated that tree density in the diameter at breast height (dbh) class of < 20 cm increased during shelterwood cutting. Canopy cover of regeneration unit was 78.5% in 1957, while in 2000 and after the shelterwood cutting it reached 59%. Growing stages of regeneration were 14% sapling, 21% thicket, 24% small pole and 41% pole. The shelterwood method has not been very successful in our study area due to a number of technical and potential problems.

Some new findings of Cryphonectria parasitica (Murrill) M. E. Barr in the Czech Republic

Libor Jankovský, Pavlína Haltofová, Dagmar Palovčíková

Plant Protect. Sci., 2010, 46(1):19-24 | DOI: 10.17221/40/2009-PPS

This study provides new information on the distribution of the chestnut blight agent Cryphonectria parasitica and its vegetative compatibility groups (VCGs) in the Czech Republic. This study has revealed the presence of the disease in six localities. The VCG tests showed that each locality was represented by a single distinct VCG, which was different from the others collected in the country. The tests with 31 European testers of C. parasitica VCGs (EU-1 to EU-31) had assigned Czech isolates to VCGs EU-1, EU-4, EU-12, EU-13, EU-15, and EU-19. Moreover, the study showed that in the Czech Republic chestnut blight attacks young trees, not exceeding 35 years of age, and that climatic conditions in the country are suitable for C. parasitica. As two of the diseased localities were ornamental tree nurseries, one might expect its further spread over the country as a result of plant trade. The origin of infection remains unknown in all the localities where C. parasitica was detected.

Evaluation of phosphorus mobility in soil using different extraction methods

M. Kulhánek, J. Balík, J. Černý, V. Vaněk

Plant Soil Environ., 2009, 55(7):267-272 | DOI: 10.17221/43/2009-PSE

Soil samples (from Czech and German long-term field experiments) were used to estimate different soil phosphorus (P) fractions. More than 200 topsoil (0-30 cm) samples from different fertilizing treatments were taken. These were analyzed for P in soil solution (PCaCl2) [0.01M CaCl2 extract], exchangeable sorbed P (Pex) [anion exchange (AE) membranes] and bioavailable P [Doppel-Lactat and Mehlich 3 (PDL and PM3)]. Other fractions analyzed were total inorganic (Pin), total (PM-tot) and organic (Porg) P [fractionation after Marks], P sorbed on Fe and Al (PFeAl) [fractionation after Schwertmann] and residual P (Par) [aqua regia extract]. Comparison of medians appeared to be better for evaluating extraction abilities. Phosphorus fractions were in the following order: (Par = 100%); PCaCl2 (0.2%) < Pex (9%) < PDL (10%) < PM3 (16%) < Pin (24%) < Porg (37%) < PFeAl (55%) < PM-tot (59%). Low amounts of Pin, Porg and PM-tot did not verify the applicability of the Marks' fractionation for the set of studied soils. Close correlations at P ≤ 0.001 were found for all methods for estimating the fractions of bioavailable phosphates (PCaCl2, Pex, PDL and PM3). Statistically significant relations were observed between Pin with Par, PM-tot and PFeAl.

Relationships between longevity and conformation traits in Czech Fleckvieh cows

L. Zavadilová, E. Němcová, M. ©típková, J. Bouąka

Czech J. Anim. Sci., 2009, 54(9):385-394 | DOI: 10.17221/1685-CJAS

The relationships between conformation and longevity traits were analysed in 58 493 Czech Fleckvieh cows first calved from 1994 to 2003. All cows were scored for conformation during the first lactation. Genetic correlations between longevity and conformation traits were estimated by bivariate runs using the VCE 4.0 program for variance component estimation. The values of heritability for conformation traits were in the range from 0.06 to 0.63 and for longevity traits from 0.04 to 0.05. Low or intermediate genetic relationships between recorded linear traits and longevity trait were found. The correlations were lower for functional longevity. Body measurements showed negative genetic correlations with real as well as functional longevity (-0.12 to -0.29). The dairy character negatively correlated with longevity traits (-0.18 to -0.26). The muscularity and udder showed a zero correlation with functional longevity, while the feet and legs were not correlated with real longevity. The highest positive genetic correlations between real longevity and objectively scored linear type traits were found for hock (0.24), rear udder attachment (0.28), fore udder length (0.16) and central ligament (0.11). On the contrary, the correlation between the udder depth and the milk-corrected longevity was positive (0.28) and higher than in the case of real longevity.

The relationship between seed coat color and seed quality in watermelon Crimson sweet

K. Mavi

Hort. Sci. (Prague), 2010, 37(2):62-69 | DOI: 10.17221/53/2009-HORTSCI

This work was carried out to determine the relationship between seed coat color and seed quality in Crimson sweet watermelon. Seed lots (1, 2, 3, and 4) were prepared taking into consideration seed coat colors in fresh seeds with naked eye. The color parameters of these prepared seed lots were determined using Minolta colorimeter. To determine quality differences between the seed lots, standard germination test, seed weight, water uptake ratio, mean germination time, emergence percentage, mean emergence time, seedling fresh weight, seedling dry weight and electrical conductivity values were determined. The seed weight (57.22 mg), germination percentage (86.5%), emergence percentage (77.5% total and 76.5% normal), seedling fresh weight (978.7 mg), and dry weight (64.7 mg) of the brown seed lot (Lot 1) were markedly higher than lots having lighter seed coat (2, 3, and 4). On the other hand the mean emergence time (7.7 days) and electrical conductivity value (128.8 μS/cm g in 24 h) of the brown seed lot (Lot 1) were lower than lots having lighter seed coat (2, 3, and 4). The obtained data indicated that seed quality differences can be determined according to the seed coat color of Crimson sweet seeds. It was found that seed lot 1 had higher seed vigor and viability than seed lots 2, 3, and 4. Color parameters b*, C*, L*, and H°, determined by Minolta colorimeter, showed significant correlation with seeds quality parameters.

Incidence of psychrotrophic lipolytic bacteria in cow's raw milk

R. Cempírková, M. Mikulová

Czech J. Anim. Sci., 2009, 54(2):65-73 | DOI: 10.17221/1667-CJAS

The contamination of bulk samples of cow's raw milk (n = 491) by psychrotrophic lipolytic bacteria (PLiBC), total count of psychrotrophic bacteria (PBC) and mesophilic bacteria (TBC) was monitored for two years on eight dairy farms and the correlations among these groups of bacteria were analysed. An increase in TBC, PBC and PLiBC and in the values of free fatty acids (FFA) was tested experimentally in three milk samples in relation to time (analyses were done in 24-hour intervals until 96 hours) and storage temperature of milk samples (4; 6.5 and 10°C). Bacterial contamination of milk was determined by culture methods in accordance with IDF standards, the values of FFA were determined by an extraction-titration method. These mean values were determined in the set of samples (n = 491): PLiBC 659 CFU/ml, PBC 2 932 CFU/ml and TBC 18 932 CFU/ml. A high correlation was proved between values of PBC and PLiBC (r = 0.87; P < 0.001) while the correlation between TBC and PBC (r = 0.65; P < 0.001) and between PLiBC and TBC (r = 0.59; P < 0.001) was on a medium level. The proportional index pI for PLiBC/PBC was 0.20, for PLiBC/TBC 0.03 and for PBC/TBC 0.16. In seasonal dynamics a statistically significant difference (P < 0.001; P < 0.05) between the increased values of TBC in the summer season was proved compared to the winter and spring season. The differences in the seasonal variation of PBC and PLiBC values were not significant. Experimental investigation of an increase in the values of tested parameters showed that at temperatures of milk sample storage 4 and 6.5°C TBC did not exceed the permissible hygienic value (100 000 CFU/ml) even after 96 hours while at 10°C it amounted to 90 000 CFU/ml after 48 hours and the limit for TBC was exceeded several times after 96 hours. PBC, which is not inhibited by cold storage to such a large extent, did not exceed the hygienic limit value for PBC (50 000 CFU/ml) even after 96 hours when milk samples were stored at 4°C, but at 6.5°C after 72 hours and at 10°C already after 48 hours the values 6 and 20 times higher, respectively, than the hygienic limit were recorded. A similar trend was observed in PLiBC, which exceeded the hazardous limit (43 000 CFU/ml) at 6.5°C after 96 hours and at 10°C already after 48 hours whereas at 4°C the limit value was not exceeded even after 96 hours. The content of FFA also increased in relation to the storage time and temperature of milk samples but in comparison with the increase in the tested groups of microorganisms the increase in FFA showed a higher correlation with storage time compared to storage temperature. A medium correlation was calculated between PLiBC and/or PBC and FFA content (r = 0.52; r = 0.57; P < 0.001).

Growth characterisation of Staphylococcus aureus in milk: a quantitative approach

Alľbeta Medveďová, Ąubomír Valík, Zuzana Sirotná, Denisa Liptáková

Czech J. Food Sci., 2009, 27(6):433-453 | DOI: 10.17221/24/2009-CJFS

Staphylococcus aureus is a pathogenic bacterium that induces several of human illnesses. The staphylococcal enterotoxin (SE) production as the results of previous growth of toxigenic strains is the most crucial problem which may lead to the staphylococcal food poisoning outbreaks in humans. That is why the growth of three strains of Staphylococcus aureus was characterised in milk and modelled in dependence of temperature. For the lag phase duration of S. aureus 2064, the Davey model was used with the following result: ln(1/lag) = 1.973 - 87.92/T + 285.09/T2 (R2 = 0.962). The dependence of the growth rate on incubation temperature was modelled by the Ratkowsky square root model and Gibson in sub-optimal and whole temperature range, respectively. The validation of both models showed high significance of the growth rate data fitting. The optimal temperature of Topt = 38.5°C was resulted from Gibson model for the S. aureus 2064 growth in milk. For practical purpose, the time necessary for the increase of S. aureus by 3 log counts was also calculated within the growth temperature range. These data may provide useful information e.g. for the producers using raw milk in their artisanal cheese practice as the specific strains were used in this study.

Genetic and biological characterisation of a Grapevine virus A isolate from the Czech Republic

Petr KOMÍNEK, Marcela KOMÍNKOVÁ

Plant Protect. Sci., 2008, 44(4):121-126 | DOI: 10.17221/24/2008-PPS

An isolate of Grapevine virus A (GVA) from the Czech Republic was obtained from the grapevine cultivar Müller Thurgau. Symptoms of GVA - Kober stem grooving disease were not observed in the infected grapevines (which had been grafted onto Kober 5BB rootstock). A partial genomic sequence of the GVA isolate, 1523 nucleotides long, was obtained. The sequence completely covers the genes for both a movement and a coat protein. Compared to the GVA sequences available in databases, the nucleotide identity reached 84%. The amino acid identity in the movement protein reached 88%, and 98% in the coat protein.

Antioxidant Activity in Variously Prepared Elderberry Foods and Supplements

K. Cejpek, I. Malouąková, M. Konečný, J. Velíąek

Czech J. Food Sci., 2009, 27(10):S45-S48 | DOI: 10.17221/951-CJFS

Antioxidant capacity of foods and food supplements based on berries and flowers of medicinal plant elderberry (Sambucus nigra L.) was assessed. Reducing properties of the samples and extracts were evaluated using amperometric detection at working electrode potential -0.8 V after HPLC separation. Moreover, antiradical activity of selected samples was determined by the means of spectrophotometric DPPH radical scavenging method. Electrochemical activity (EA) of fresh juice pressed from elder fruits amounted to 0.71 g AAE/l with anthocyanins as minor contributors (10.2%). Catechins and phenolic acids were the major active groups. During production of elder berry spread, even more than 90% of the EA compounds found in raw elder berry material can be destroyed. Comparable activity may be found also in the products from elder flowers. Although elder blossom syrups possessed similar EA regardless of the technology used (0.033-0.054 g AAE/kg), their chromatographic patterns were often very different. For example, no flavonols were present in the syrups, if traditional preparation comprising 24-h maceration with citric acid was applied. Analyzing the chromatographic patterns, one can distinguish different base materials and technology, which can be used for the authenticity confirmation. Herbal infusions from elder flowers, which contain more flavonols than are in syrups, were 16-27 times richer in EA than drinks prepared from the syrups after recommended dilution. Only the syrup designed for preventing and treating upper-respiratory viral infections showed the EA (0.09 g AAE/kg) comparable to that of herbal infusion (0.13 g AAE/l).

Decontamination of cut carrot by Persteril® agent based on the action of peroxyacetic acid

Aleą Landfeld, Vladimír Erban, Eliąka Kováříková, Milan Houąka, Karel Kýhos, Jiřina Průchová, Pavla Novotná

Czech J. Food Sci., 2010, 28(6):564-571 | DOI: 10.17221/212/2008-CJFS

The use of cleaned and cut fresh vegetables for direct consumption without cooking is limited by the short shelf life caused by the fast growth of contaminating microflora. With the aim of reducing the contamination, we tested the possible use of peroxyacetic acid (brand name Persteril) as an additive. Peroxyacetic acid breaks down quickly into oxygen and acetic acid; with the latter quickly vaporising through the packaging. Tests were carried out on a model of pre-washed, cut, and re-washed carrots, which were left naturally contaminated to resemble real grocery store conditions. Four decontamination regimens were applied: (1) rinsing with ordinary tap (drinking) water, (2) rinsing with a 0.2% solution of Persteril, (3) rinsing with a 0.2% solution of Persteril + the addition of concentrated Persteril into the packaging before sealing, and (4) rinsing with a 0.2% solution of Persteril + the addition of concentrated Persteril into the packaging before sealing + another addition of concentrated Persteril after 24 hours. The total number of aerobe mesophilic microorganisms (TNM) and the numbers of yeasts and molds were monitored in the samples taken during 28-days of storage. The last decontamination regimen reduced the initial contamination by TNM by about 1× 104 CFU/g or 4 log units and no further microbial growth was observed during storage. Yeasts and molds were reduced by about 3.16 × 103 CFU/g or 3.5 log units. No statistically significant changes in colour, texture or taste were noted during storage. There was a slight change immediately after the application in the odour of samples treated with concentrated Persteril; however, the odour returned to original levels during storage.

Boron sorption in soils and its extractability by soil tests (Mehlich 3, ammonium acetate and water extraction)

J. Matula

Plant Soil Environ., 2009, 55(1):42-49 | DOI: 10.17221/377-PSE

The aim of the paper was to contribute to the acquisition of background data for the specification of safe boron levels in soils in relation to diagnostics by multi-nutrient soil tests and to CEC (cation exchange capacity) value of soil, pH and soil organic matter. The research was conducted on 24 soils. Sorption was determined after 97 days from the application of B at the rates of 0, 1, 2.5, 5 mg B/kg in H3BO3. The closest regression of B-sorption was with the CEC value of soil in NH4-acetate and water tests and it increased with the increasing application of B (regression at a rate of 5 ppm B; NH4-acetate: linear R

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