首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   15篇
  免费   2篇
林业   1篇
  1篇
农作物   1篇
水产渔业   12篇
畜牧兽医   1篇
植物保护   1篇
  2019年   1篇
  2018年   2篇
  2017年   3篇
  2016年   1篇
  2014年   6篇
  2013年   1篇
  2011年   1篇
  2010年   1篇
  2007年   1篇
排序方式: 共有17条查询结果,搜索用时 31 毫秒
1.
2.
The effect of sodium and potassium concentrations as well as optimal pH on the motility of common carp Cyprinus carpio L. sperm during short-term storage in artificial seminal plasma (ASP) was investigated. Sperm was collected from individual males (n?=?5) and each sample diluted tenfold (1:9) in ASP (sperm:extender) containing 2 mM CaCl2, 1 mM Mg2SO4 and 20 mM Tris at pH 8.0 and supplemented by the following concentrations of sodium and potassium (mM/mM): 0/150, 20/130, 40/110, 75/75, 110/40, 130/20 and 150/0. The osmolality of all ASP variants was set at 310 mOsm kg?1. Sperm motility was measured using a CASA system during 72 h of storage. Immediately after dilution, sperm motility was high (90%) both in each variant and in the control group (fresh sperm). After 72-h storage, the highest sperm motility was noted in ASP containing 110 mM NaCl and 40 mM KCl. No differences were found in the motility of samples preserved within the pH range of 7.0–9.0. Our data suggest that for the short-term storage of common carp sperm, whereas the pH of the solution does not play a crucial role, a specific potassium concentration of around 40 mM is required.  相似文献   
3.
The addition of cryoprotectants during the freezing of semen in liquid nitrogen protects spermatozoa from the negative influence of freezing. Every species needs an appropriate cryoprotectant that has to be experimentally selected. Semen obtained from five perches was diluted with the Kobayashi buffer solution at 1:9 ratio. To determine the influence of cryoprotectants on spermatozoa motility parameters, the same type of buffer solution was applied with the addition of methanol, dimethyl sulfoxide (DMSO) and dimethylacetamide (DMA) using the concentration of 10, 5, 2.5 %, respectively, glycerol (15; 7.5 %), sucrose and trehalose (0.45; 0.225; 0.113 M). After the preparation of such tests, parameters of spermatozoa motility were measured, using the CASA system (Image House CRISMAS Company Ltd.). Among used cryoprotectants, methanol did not cause any effect on the sperm motility parameters. The lowest percentage concentrations of DMA, DMSO, glycerol, sucrose and trehalose did not significantly influence the percentage of motile spermatozoa. Higher concentrations of these compounds considerably lowered all motility parameters. As for glycerol and saccharides, their addition resulted in the lowering of the spermatozoa motility possibly due to a higher viscosity of the solution. However, DMA and DMSO were most probably toxic to perch sperm cells. The obtained results indicate that the best cryoprotectant to be used with perch spermatozoa is methanol.  相似文献   
4.
5.
The aim of this work was to compare the effects of controlled reproduction of cultured and wild common barbel, Barbus barbus (L.). Preparations containing different GnRH analogues and dopamine receptor antagonists (Ovopel, Ovaprim) as well as human chorionic gonadotropin (hCG) (in the case of cultured fish) were applied and their influence on ovulation, spermiation and quality of gametes obtained was determined. No differences in the qualitative or quantitative parameters of semen were found between fish stimulated with different hormonal preparations and those not receiving hormonal stimulation. The high suitability of Ovaprim for ovulation induction in (cultured and wild) barbel was confirmed. The highest synchronisation of ovulation was obtained after the application of Ovopel (18 ± 3 h), but the best results of controlled reproduction (expressed as the percentage of ovulations and survival of embryos) were obtained by applying Ovaprim (83.2 ± 4.1). A significantly higher percentage of ovulation was obtained in cultured fish (80-90%) than in wild fish (< 25%).  相似文献   
6.
The effectiveness of applying Ovaprim [(D-Arg6, Pro9NEt)-sGnRH + domperidone] and Ovopel [(D-Ala6, Pro9NEt)-mGnRH + metoclopramide] to male barbel Barbus barbus (L.) 6, 12 and 24 h after hormonal stimulation was analyzed. The control group (Control) during each time interval was stimulated with 0.9 % NaCl. Milt was collected from seven fish only once (n = 7) for Ovopel, Ovaprim and Control group in order to determine total volume of milt, volume of milt per kg of body weight, sperm concentration, total sperm production, seminal plasma osmotic pressure, pH of milt and pH of seminal plasma. Woynarovich’s solution (68 mM NaCl + 50 mM urea) with the addition of 0.5 % BSA (pH 7.7; 181 mOsm kg?1) was used as the activating liquid. Selected parameters of sperm motility (MOT %) and progressively motile sperm (%), curvilinear velocity (VCL, μm s?1), straight-line velocity (μm s?1), movement linearity (%), wobbling index (%), amplitude of lateral head displacement (μm) and beat cross frequency (Hz) were determined using the Computer-assisted sperm analysis system. A time of 6 h proved to be too short to obtain milt from barbel following hormonal stimulation with Ovaprim and Ovopel. Extending the time to 12 h, however, resulted in 100 % spermiation in males, regardless of hormonal preparation used for stimulation. The stimulation of spermiation in barbel is best performed using Ovopel 12 h upon application. Extending the latency period to 24 h following the application of this preparation results in a significant decrease in the volume of milt obtained, sperm count and motility parameters, including MOT and VCL, which may influence sperm fertilization ability.  相似文献   
7.
Here, we investigated the effect of dietary resveratrol (20, 40, and 80 µg/g BW/day) on cell-mediated immunity (activity of spleen phagocytes and proliferative response of lymphocytes) and reproductive parameters (egg and sperm quality, i.e. fecundity—total number of eggs produced by individual fish, fertility, embryo survival, and hatching rate) in medaka. Fish fed feed with resveratrol at 40 and 80 µg/g BW/day had significantly higher metabolic activity and intracellular phagocyte killing activity than control. The proliferative lymphocyte activity of the fish from R80 group was greater by more than 20 % in comparison with the control group (P < 0.05). The percentage of macrophages (MO) and their mean fluorescence intensities (MFI) in R40 and R80 groups were significantly higher compared to C and R20 groups (P < 0.05). The differences in MO and MFI values ranged from 52.5 % (±1.5; R0 group) to 65.8 % (±1.6; R80 group) and from 23.2 (±1.4; R0 group) to 38.2 (±2.4; R80 group), respectively. Moreover, resveratrol at 80 µg/g BW/day decreased liver COX activity, i.e. 5.4 in R80 group and 7.9 in R0 group (P < 0.05). The motility parameters of the sperm obtained from the males fed feed supplemented with resveratrol at 80 µg/g BW/day exhibited the highest values except the linearity, which was lower as compared to the control (P < 0.05). The results indicate that diet supplemented with resveratrol at a dosage of 40 µg/g BW/day improves phagocyte killing ability and lymphocyte proliferation in broodstock and accelerates offspring hatch. Also, the results suggest that COX activity influences sperm and oocyte quality in fish; the presence of a COX inhibitor in the dose of 40 µg/g BW/day decreased the embryo survival.  相似文献   
8.
Broodstock of mature Japanese medaka (Oryzias latipes Temminck and Schlegel, 1846) (mean weight 0.45 ± 0.03 g; age 6 months) were maintained in glass aquaria (8 males and 8 females in each aquarium). The fish were fed commercial feed (group C) or this feed was supplemented with arachidonic acid ARA (2 % of total fatty acids in feed; group A) and one of the COX inhibitors: resveratrol (group AR) or NS-398 (group ANS) with amount 20 mg kg?1 BW day?1 of one of the COX inhibitors. The effect of 2 weeks of feeding experimental diets on reproductive parameters (fecundity, embryo and larval survival, hatching rate, and larvae body weight) was analyzed. Larvae (obtained from experimental dietary treatments) were reared for 2 weeks. The percent of spawning female and fecundity was similar in dietary treatments. COX inhibitors in broodstock diet caused a decrease in embryo survival rate. Eggs of medaka from group ANS and AR revealed the lowest hatchability rate. In contrast, group A revealed a higher hatchability rate at the same time. Larval body weight after hatching was significantly the highest in this group. At the end of the experiment, larvae body weight ranged from 1.62 ± 0.43 mg in group AN to 2.89 ± 0.74 mg in group A. These results show that the COX inhibitors decreased gamete and larval quality regardless of high levels of ARA in broodstock diet.  相似文献   
9.
The qualitative and quantitative evaluation of triterpene aglycones of saponin fractions isolated from vegetative and generative organs of three Silphium species, Silphium perfoliatum, Silphium trifoliatum, and Silphium integrifolium, as compared to materials used in the herbal industry such as Panax quinquefolium root and Calendula officinalis flower, was performed. The analyses revealed that triterpene aglycones of saponins isolated from tested Silphium and Calendula species were oleanolic acid and ursolic acid. It was found that Panax roots contained only the aglycone of oleanolic acid within the triterpene saponin group. The leaves of Silphium harvested in May were characterized by the highest content of oleanolic acid-They contained 17.03 mg/g dry weight of the triterpenic acid, on average. The seasons before flowering and at the beginning of that stage appeared to be the most efficient periods for leaf collection in reference to triterpene aglycone contents in plant yield. Moreover, it was found that inflorescences of S. trifoliatum and S. integrifolium contained oleanolic acid in amounts of 22.05 and 17.95 mg/g dry weight respectively, whereas Calendula flowers contained 20.53 mg/g dry weight. The oleanolic acid content in Panax roots was 3.15 mg/g dry weight. Ursolic acid most abundantly occurred in S. integrifolium and S. trifoliatum at concentrations of about 14.98 mg/g dry weight in leaves harvested before flowering (June) and to 15.50 mg/g dry weight in leaves collected during flowering.  相似文献   
10.
The common carp, Cyprinus carpio L., sperm motility parameters were analyzed by using computer‐assisted sperm analysis system. The percentage of motile sperm (MOT, %), progressively motile sperm (PRG, %), curvilinear velocity (VCL, µm/sec), average path velocity (VAP, µm/sec), the wobbling index (WOB, %), movement linearity (LIN, %), beat cross frequency (BCF, Hz), and amplitude of lateral head displacement (ALH, µm) were determined. Five activation solutions (As) were used to activate sperm movement. As 1 solution: 68 mM NaCl, 50 mM urea, 0.5% bovine serum albumin (BSA), pH: 7.7, 181 mOsm/kg; As 2 buffer: 100 mM NaCl, 10 mM Tris, 0.5% BSA, pH: 9.0, 199 mOsm/kg; As 3 solution: 86 mM NaCl, 0.5% BSA, pH: 7.4, 167 mOsm/kg; As 4 buffer: 5 mM KCl, 45 mM NaCl, 30 mM Tris, 0.5%, pH: 8.0, 160 mOsm/kg; and As 5 solution: distilled water with the addition of 0.5% BSA, pH: 7.3, <3 mOsm/kg. Among five tested solutions, a buffer with a pH of 9.0 and osmolality of approximately 200 mOsm/kg (As 2) was the most suitable. After its activation, a significant increase in MOT and ALH values was observed, which can be of importance to the effectiveness of egg fertilization .  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号