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91.
Fertilizing ability of gametes at different post‐activation times and the sperm–oocyte ratio in the artificial reproduction of pikeperch Sander lucioperca 下载免费PDF全文
Jiri Kristan Daniel Zarski Miroslav Blecha Tomas Policar Oleksandr Malinovskyi Azin Mohagheghi Samarin Katarzyna Palinska‐Zarska Joanna Nowosad Slawomir Krejszeff Dariusz Kucharczyk 《Aquaculture Research》2018,49(4):1383-1388
The time period during which oocyte and spermatozoa retain their fertilizing ability after contacting with water was evaluated in pikeperch (Sander lucioperca). In addition, success of in vitro fertilization was examined regarding to the sperm‐to‐oocyte ratio (SOR). In the first trial, oocytes were placed in Petri dishes containing 5 ml of the hatchery water, to which freshly collected and pooled sperm were added to each sample at 0, 15, 30, 60, 90, 120, 150 and 180 s post oocyte activation. The oocytes retained their fertility for at least 30 s after contacting with water. The second trial tested the maximum time period during which spermatozoa retained fertilizability after contacting with water. Milt (50 μl) was collected from each male and added to 5 ml of water in Petri dishes. Thereafter, oocytes were added at 0, 5, 15, 30, 60 and 75 s post‐sperm activation. Delays exceeding 10 s affected negatively the fertilization success. The third trial examined the optimum SOR; in which was found that 100 × 103 spermatozoa per oocyte were the minimum ratio to ensure fertilization rates above 70%. Overall, the data clarified some biological interactions of gametes in the artificial propagation of pikeperch. 相似文献
92.
Edyta Łokas Przemyslaw Wachniew Dariusz Ciszewski Piotr Owczarek Nguyen Dinh Chau 《Water, air, and soil pollution》2010,207(1-4):57-71
This study focuses on the distribution of selected trace metals, 137Cs and 210Pb, in floodplain deposits of the lowland Warta River (southern Poland) downstream of Cz?stochowa, a large city with an iron smelter. The depth profiles of trace metal (Zn, Pb, Cu, Ni, Cd and Mn), 210Pb and 137Cs contents in floodplain sediments were used to derive deposition rates on the floodplain for the twentieth century. The applicability of particular chronometric tools is considered within the context of their mutual relationships and confirmed by the consistency of the results. Deposition rate estimates for the past 50 years based on the vertical patterns of trace metal concentrations, which were correlated with particular events in the development of the smelter, range from 0.4 cm·year?1 in profiles situated in backswamps far from the channel to over 1.1 cm·year?1 in profiles of the natural levee adjacent to the river. Deposition rates based on 210Pb inventories in the profiles range from 0.08 to 0.66 g·cm?2·year?1, which corresponds to linear sedimentation rates of 0.10 to 0.91 cm·year?1, respectively. Dating of characteristic levels associated with peak fallout of 137Cs gives sediment accretion rates resembling those obtained from trace metals and 210Pb. The period of the highest sediment accumulation rate could be related to the highest loads of effluent from the iron smelter and city of Cz?stochowa, which were substantially reduced after the construction of effluent treatment plant. 相似文献
93.
An olfactory sexual recognition signal was investigated in Tetrodontophora bielanensis (Collembola: Onychiuridae). A preliminary olfactometry experiment showed an unequivocal attraction of males by the odor of females. This led us to conduct male attraction tests using polar and apolar fractions of female cuticular extract. The polar fraction of the extract was shown to contain the component that plays an active role in sexual attraction in this Collembola species. The results of the present study are the first to show a direct relationship between an olfactory signal and sexual attraction in Collembola. 相似文献
94.
Bednarek D Kondracki M Friton GM Trela T Niemczuk K 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(7-8):305-308
The influence of treatment with steroidal (SAIDs) and non-steroidal (NSAIDs) anti-inflammatory drugs on inflammatory markers in thirty, 6-8 week old calves with induced bronchopneumonia was investigated. Animals received a single intravenous treatment with meloxicam (0.5 mg/kg body weight), flumethasone (0.05 mg/kg body weight) or sterile 0.9% NaCl (10 ml per animal). Body temperature, respiratory and heart rate, concentration of prostaglandins PGE2, PGF2alpha, thromboxane (TXB2), leukotriene (LTB4) and malonyldialdehyd (MDA) and proinflammatory cytokines i.e. tumor necrosis factor (TNFalpha) and interferon (INFalpha) were recorded in serum, bronchoalveolar lavage (BAL) and blood platelets (BP). A significant reduction of main inflammatory mediators PGE2, PGF2alpha,TXB2 and MDA after meloxicam treatment in calves with induced bronchopneumonia indicates a beneficial effect on the inflammatory processes. Contrary to effects observed by flumethasone, meloxicam induced an increase of LTB4 and INFalpha indicating that it is not immunosuppressive. 相似文献
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Karol Trejchel Daniel Żarski Katarzyna Palińska-Żarska Sławomir Krejszeff Bartłomiej Dryl Krzysztof Dakowski Dariusz Kucharczyk 《Aquaculture International》2014,22(1):195-203
The aim of the study was to optimize burbot juveniles rearing in recirculating aquaculture system. In experiment 1 (17 °C, photoperiod 24L:0D), the fish (initial: body weight [W] = 15.36 ± 3.72 g, standard length [SL] = 12.48 ± 1.09 cm) were divided into four groups (I, II, III and IV). Different feeding levels were applied: 1, 2, 3 and 4 % of biomass daily (counted based on dry feed weight). The feed conversion ratio (FCR) and specific growth rate (SGR) were recorded. In experiment 2 (17 °C, feeding level of 2 % of biomass day?1), fish (W = 5.24 ± 2.43 g and SL = 8.54 ± 1.24 cm) were divided into two groups where different light conditions were applied (I: 24 h light [1,800 lx] and II: 24 h darkness [4 lx]). In experiment 1, the highest SGR was recorded in group II (1.93 % day?1), whereas the lowest SGR (1.27 % day?1) and final W (P < 0.05) was in I group. The lowest (P < 0.05) FCR (0.63) was in group II. In the remaining groups, FCR was similar (0.68–0.70, P > 0.05). The feed consumption in group I reached 100 %, in group II, it was 71.3 % (P < 0.05) and it was the lowest in groups III (39.26 %) and IV (36.93 %). In experiment 2 no differences in the growth and survival rate were recorded (final SL between 14.16 and 14.19 cm, P > 0.05; W between 23.33–23.35 g; P > 0.05). The results from experiment 1 indicate that the feeding 2 % of biomass day?1 was the most efficient. Also, it was proven, for the first time, that there was no effect of using different constant light conditions. 相似文献
97.
Reciprocal hybrids between tench Tinca tinca (L.) and carp Cyprinus carpio L., and tench and bream Abramis brama (L.) were produced artificially. The survival of all these hybrids during embryogenesis was quite high. The highest survival
rate (over 60%) at the eyed stage was observed for tench and bream hybrids (both sex combinations). The hatching rates of
these hybrids were also over 60%. The number of larvae with some abnormalities (i.e. deformed body) was low. In contrast,
the hatching rates of tench and carp hybrids were very low (0.2%). From over 1000 fertilized eggs, only three specimens started
swimming, and only one specimen survived to juvenile stage. Embryos of hybrids and their parental species differ in morphological
features. These differences were also visible in the juveniles. Body parameters of juvenile hybrids produced from three species
had intermediate values in comparison to parental fish. 相似文献
98.
Heavy metal concentrations were investigatedin the overbank sediments in the middle reach of the regulatedOdra River, in south-west Poland. Samples of sediments weretaken in 20 vertical profiles to a depth of 70 cm at 1–20 cmintervals. Regulation and lateral stability of the riverchannel for over 150 years enabled to follow the decrease indepth of the Cu and Pb concentration peaks across thefloodplain. These peaks were recognised at different depth ofthe particular profiles: at about 40 cm in the inter-groininfills several meters from a river bank, at 25 cm in thelevee at the edge of the floodplain, at several cm in crevassesplays and depressions parallel to flood-protectionembankments. These peaks are correlated with maximum Cu and Pbemission and discharge of the mine effluents polluted withheavy metals in the Legnica Copper District at about 1980.Moreover, in profiles localised close to river banks, thereare two peaks of Zn concentrations. The upper peak was datedat about 1987 and seems to be associated with the changes inamount of effluents discharged to surface waters in the upperand middle Odra River catchment. The lower one was dated atthe first half of the 1940s and can be related to changes inindustrial potential and population density after World WarII. Dates of sediment layers in different vertical profilesshow that the highest rate of sediment accretion, 10–20mm yr-1, has occurred in the inter-groin infills. Much lowerrate, 3–6 mm yr-1, has typified the levee on the 3 m-highfloodplain and the lowest one, up to 1–2 mm yr-1, is found increvasse splays on the flood plain. 相似文献
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The purpose of this study was to examine the drying and grinding characteristics of sprouted and crushed wheat. The four‐day‐germinated wheat kernels were crushed, dried, and ground in a micro hammer mill. The drying kinetics of sprouts were best described by the Page and two‐factor models. The crushing of wheat sprouts before drying decreased the drying time by about half. Sprouting and crushing of wheat sprouts have a significant influence on the grinding process, both on the particle size distribution and on the grinding energy requirements. It was observed that the ground sprouts showed significantly lower values of average particle size compared with the samples of sound kernels. Sprouting caused an increase in the amount of fine particles (<0.2 mm) and a decrease in the mass fraction of coarse particles (>1.0 mm). All values of grinding indices showed that sprouting and crushing significantly reduced the grinding energy requirements. Moreover, sprouting significantly increased the total phenolics content (from 26 to 31%) and antioxidant activity (from 33 to 72%) of wheat kernels. The results showed that sprouting and crushing of sprouts followed by their drying and grinding may provide a practical method for preparing sprouted flour. 相似文献