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41.
Activities of phytase, a pH 6.0 optimum nonspecific phosphomonoesterase and phosphodiesterase assayed toward bis(p-nitrophenyl)phosphate (phosphodiesterase I) and against p-nitrophenylphosphorylcholine (phosphodiesterase II), were partially purified from mycelial extracts of Aspergillus niger AbZ4 cultivated on a molasses medium by a liquid surface fermentation method. After elimination of phosphate from the medium, 7.3- and 3.5-fold enhancements in specific activities of phytase and phosphodiesterase II were observed. Efficacies of mycelial protein fractions in dephosphorylating a wheat-based broiler feed were determined in vitro according to a procedure that simulated digestion in the intestinal tract of poultry. The addition of 0.052 mg of protein from fractions, each of which was high in either pH 6.0 optimum phosphomonoesterase, phosphodiesterase I, phosphodiesterase II, or phytase per gram of a feed sample resulted in the enhancement of phosphorus release by 10, 11, 27, and 88%, respectively. In the presence of an excess of commercial phytase, the addition of the mycelial fraction high in phytase increased the dephosphorylation rate by 56%. The fraction high in phosphodiesterase II enhanced feed dephosphorylation by 8% in the presence of an excess of commercial phytase and commercial acid phosphatase. 相似文献
42.
Katarzyna Andraszek Dorota Banaszewska Olga Szeleszczuk Piotr Niedbała Marta Kuchta-Gładysz 《Reproduction in domestic animals》2020,55(4):515-522
Sperm cells isolated from the tail of the epididymis and from the semen of the same individuals were analysed. The use of silver nitrate to stain sperm cells isolated from the tail of the epididymis made it possible to identify structures that were not visible in the sperm from semen. Silver nitrate very clearly distinguished the acrosomal and distal parts of the sperm head. Following silver nitrate staining, the sperm isolated from the tail of the epididymis were characterized by dark ‘collars’ in the distal part of the head. These ‘collars’ are not visible in the sperm cells isolated from semen. The results of the study indicate differences in the dimensions of sperm isolated from the tail of the epididymis and sperm in semen. Sperm isolated from the tail of the epididymis had smaller heads, despite their longer length, and had longer midpieces and tails than ejaculate sperm. Silver nitrate staining is a simple and fast technique. Silver nitrate makes it possible to identify the acrosome and post-acrosomal region of the sperm head and to clearly identify the midpiece. Therefore, it can be successfully used to supplement routine techniques for evaluating sperm morphology or as an independent technique. 相似文献
43.
Anna Trojak-Goluch Dorota Laskowska Monika Agacka Diana Czarnecka Magdalena Kawka Anna Czubacka 《Breeding Science》2011,61(4):389-393
Black root rot (BRR) caused by Thielaviopsis basicola as well as Tomato spotted wilt virus (TSWV) are the most serious problems in tobacco growing regions. We crossed the breeding line WGL 3 carrying BRR resistance derived from N.glauca with the line PW-834 the resistance of which to TSWV was transferred from cultivar Polalta. Anthers obtained from F1 hybrid plants were cultured to induce haploids combining resistance to Th. basicola and TSWV. Flow cytometry analysis revealed 242 haploids and 2 spontaneous doubled haploids among regenerants. All haploids were cloned and then evaluated for BRR as well as TSWV resistance. The presence of pathogens was detected by microscopic evaluation of roots or using DAS-ELISA test. Microscopic assessment showed that, 132 haploids had no symptoms of Th. basicola which, together with the absence of symptoms in the F1 hybrids, indicated a dominant monogenic mode of inheritance. At the same time only 30 haploids demonstrated resistance to TSWV. SCAR markers associated with TSWV resistance gene detection was applied. The results indicate that small proportion of TSWV-resistant haploids is probably due to the influence of deleterious genes flanking the resistance factor that reduced vitality of gametophytes. Altogether, 24 haploids showed multiple resistance to Th. basicola and TSWV. 相似文献
44.
Dorota Fopp-Bayat Malgorzata Jankun Pawel Woznicki & Ryszard Kolman 《Aquaculture Research》2007,38(12):1301-1304
The aim of the present study was to produce Acipenser baeri× (Huso huso×Acipenser ruthenus) hybrids in a diploid and triploid state and to study their viability in comparison with the A. baeri from the fish farm stock. A heat shock (37°C) in the 18th minute after fertilization was applied to induce triploidy. The survival rate and the ploidy level of the hybrids obtained were studied. The mortality of triploid hybrids was approximately twice as high as the mortality of diploid hybrids. No significant difference in the survival rate between Siberian sturgeon and their diploid hybrid with bester was noted. Cytogenetic analysis was performed by preparing chromosomes from the gill epithelium. The results showed that all studied fish from the heat‐shocked group were triploid. 相似文献
45.
Seven Warmblood horses without sport experience were trained and filmed four times during free jumping, with a 1-month interval between each investigation. Jumping parameters were measured on selected frames by means of video image analysis. Linear and angular parameters describing takeoff, landing, and lifting of limbs above the obstacle were studied. Statistical analysis revealed that the following parameters were affected by training: hind limbs distances at takeoff and landing, lifting of the limbs above the obstacle, and the angle of bascule. 相似文献
46.
Robert Klewicki Dorota Konopacka Małgorzata Uczciwek Zbigniew Irzyniec Ewelina Piasecka Catherine Bonazzi 《The Journal of Horticultural Science and Biotechnology》2013,88(6):75-79
SummaryThe aim of our work was to measure sorption isotherms on freeze-dried and convectively-dried fruits (apple cv. Idared; sour cherry cv. English Morello; blackcurrant cv. Tiben), previously osmotically dehydrated in fructo-oligosaccharide solution, or concentrated apple juice. Isotherms were fitted using the Guggenheim-Anderson-de Boer Model. In none of the cases studied was isotherm non-continuity in the vicinity of the initial value of aw observed. All isotherms, classified as type III, demonstrated an increase in the equilibrium water content, along with an increase in water activity. A higher water content was observed in lyophilised material compared to material dried by convection. The water content in the monolayer (100 g?1 dry matter) ranged from 12.0 g for dried apple, to 17.0 g for dried sour cherry. These values can be considered as optimal in order to ensure safe storage conditions. The dried fruits should therefore be kept in a water activity range of 0.45 – 0.54 for lyophilised, and 0.46 – 0.63 for convectively-dried material. 相似文献
47.
Thielaviopsis basicola and Tomato spotted wilt virus (TSWV) are the most important problems in a moderate climate zone. Previously obtained doubled haploids (DH) of F1 hybrids of the flue-cured line WGL3 resistant to Th. basicola and the dark-cured line PW-834 carrying RTSW-al gene provided the research material. Biological tests and SCAR markers linked with TSWV were applied to confirm resistance of DH. Lines combining resistance to TSWV and Th. basicola were evaluated for morphological and chemical characteristics. Most of DH were significantly shorter than parents but two lines, 31/A/2 and 31/B/3, were close to the flue-cured WGL3. Usually DH possessed fewer leaves while one of them 31/B/3, exceeded parental forms. The doubled haploids flowered later than their parents. The most negative effect was reduced area of mid-position leaves of DH. It might be explained by a recombination during microsporogenesis in F1, however the influence of ‘Polalta’-derived RTSW-al gene cannot be excluded. Extensive line to line variation for nicotine and sugars content was not associated with the genes for TSWV and Th. basicola resistance. Biological tests and field performance of DH revealed potential to overcome the negative effect of coupling between the RSTV-al gene and genes responsible for the morphological deformations. 相似文献
48.
Roman Kujawa Dorota Fopp-Bayat Beata I. Cejko Dariusz Kucharczyk Katarzyna Glińska-Lewczuk Krystian Obolewski Mateusz Biegaj 《Aquaculture International》2018,26(1):27-36
A method for actively protecting river lamprey and increasing the number of river lamprey populations is presented as protocol of rearing stocking material. The objective of the study was to accommodate lamprey larvae during the most critical life period under controlled conditions until they reach a sufficient size, which will increase their chances to survive in the natural environment. The eggs obtained from wild breeders were incubated in Weiss’s jars at the water temperature of 12 °C. The larvae were reared in tanks set up in closed recirculating aquaculture systems. During the rearing period, the water temperature was 20 °C and the density of larvae was 150 individuals per 1 dm2 of bottom. In the initial rearing phase, the main focus was on the type of feeds and the nourishment method. It was determined that the most suitable feed type was Artemia nauplii combined with Hikari dry food. Additionally, the type of substrate was tested under controlled conditions. In this case, the optimum one was composed of sand of the grain size between 0.3 and 0.5 mm. The experiment proved that it is possible to successfully conduct river lamprey larvae rearing under controlled conditions. The growth rates are comparable to or better than those achieved under natural conditions. After 30 days of the rearing period, the lamprey larvae were 25 mm long. The results create a possibility to develop a technology for the restitution of river lamprey and other lamprey species, which are endangered throughout the world. 相似文献
49.
Laboratory-prepared muesli-type breakfast cereal (mixture of oat flakes, wheat flakes, corn flakes, hazelnuts, raisins, sunflower seeds, and flax seeds) was subjected to accelerated storage test at 60 degrees C with or without the addition of red raspberry seed extract. The oxidative changes in muesli resulting in the formation of secondary oxidation products were evaluated using solid phase microextraction (HS-SPME) and solvent-assisted flavor evaporation (SAFE) to isolate volatiles and GC-MS and chromatography-olfactometry to quantify them and determine the key odorants. During 14 days of storage the total amount of volatile compounds changed from 1.0 mg/kg, in freshly prepared muesli, to 32 mg/kg after storage. The predominant compound was hexanal; its content during storage increased 20-fold, reaching 17 mg/kg. Red raspberry seed extract addition limited the rate of lipid oxidation, and the total amount of volatiles was estimated at 11 mg/kg and that of hexanal at almost 5 mg/kg. An elevated temperature of the storage test also influenced the crucial flavor compounds determined using aroma extract dilution analysis (AEDA). The flavor dilution factor (FD) values for volatile lipid oxidation products were lower in samples with red raspberry seed extract added. 相似文献
50.
Beata Laczynska Krystyna Demska‐Zakes Mohammad Abdul Momin Siddique Dorota Fopp‐Bayat 《Aquaculture Research》2020,51(9):3623-3630
Larval growth and gonadal differentiation of gynogenetic sterlet Acipenser ruthenus were studied. The gynogenetic fish were produced by activation of albino sterlet eggs with UV‐irradiated sperm (collected from healthy coloration specimens), following by a heat shock of 34°C. Embryos were reared at 18.0 ± 0.5°C in a recirculation system and initially fed with Artemia sp. for 4 weeks and then fed with formulated feed. During the experiment, the length and weight of fish were recorded for the gynogenetic and control groups. Additionally, the analysis of gonadal sex differentiation was conducted with a 2‐week interval at 289, 303, 317, 331, 345 and 373 DPH. The mean body weight of the control group was significantly higher (p < .05) than the gynogenetic group only at 345 and 373 DPH, while the mean total body length was significantly higher at 331 and 345 DPH (p < .05). The gonad investigation was started at 289 DPH, and ~80% of females were found in the gynogenetic group during the trial period while the number of females and males was similar at 303, 331 and 373 DPH in the control group. The first symptoms of morphological differentiation appeared at 289 DPH, and the final shaping macroscopic structure of the gonad took place earlier in females than in males. 相似文献