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1.
This study was conducted to examine the utility of vitrification for bovine embryos with low‐quality grade, and simple cryoprotectants dilution method for practitioners. In Experiment 1, survival of frozen embryos was compared with that of vitrified embryos using minimum volume cooling (MVC). Then, vitrified embryos were used to confirm the optimum sucrose concentration in Experiment 2. The survival rates of embryos that had been vitrified following diluted cryoprotectants with the one‐step in‐straw method were compared with those of fresh control embryos in Experiment 3. Frozen‐thawed or vitrified‐warmed blastocysts were cultured with TCM‐199 supplemented with 100 μmol/L beta‐mercaptoethanol +5% fetal bovine serum at 38.5°C in an atmosphere of 5% CO2 in air, their survival after 24 hr were compared. The development to term of fair quality in vivo embryos after vitrification was examined in Experiment 4. Results show that survival rates of frozen‐thawed embryos were lower (p < .05) than that of vitrified‐warmed ones. When vitrified embryos were warmed in 0.3 mol/L sucrose in straws, their survival rate was 100%. The total cell numbers of vitrified‐warmed embryos were comparable to those of fresh control embryos. The six calves from 13 vitrified embryos were delivered in Experiment 4. These results indicate that MVC vitrification following one‐step cryoprotectants dilution is utilized to preserve low‐quality bovine embryos.  相似文献   

2.
The purpose of this study was to examine whether freeze‐dried germinal vesicles (GV) can be matured in vitro after being injected into enucleated fresh oocytes in pigs as an alternative method for conservation of genetic resources. Although no reduction of the size of GV (p = .094), resveratrol treatment significantly enhanced the survival rates following GV transfer (GVT) (p < .001). Supplementation with 100 or 200 mmol/L trehalose in freeze‐drying medium significantly increased the proportions of GVs with intact nuclear membrane and DNA integrity compared with the control group. Following transfer of freeze‐dried GVs into enucleated fresh oocytes, the proportion of reconstructed oocytes reached the metaphase‐II stage (2.4% ± 1.4%) was significantly lower (p < .05) than that of the in vitro matured control group (83.2% ± 2.5%), it was comparable with the GVT control group (7.4% ± 2.7%). The rates of freeze‐dried GVs with intact nuclear membrane and DNA stored at ?20°C for 5 days were significantly higher (p < .05) than those at 4°C and room temperature. The rates of intact nuclear membrane and DNA in the freeze‐dried GV stored for 15 or 30 days at ?20, 4°C and RT were not significantly different. In conclusion, matured oocytes were produced derived from freeze‐dried GVs.  相似文献   

3.
1. Survival of emu spermatozoa during in vitro storage is not affected by increasing the extracellular [K+] to the point where it does not adversely affect spermatozoa function.

2. In three experiments, the effects were studied of [K+] in a diluent in the range 12·5–80?mM/l on emu spermatozoa survival for up to 48?h at 5, 10 or 20°C.

3. At the end of the storage period, spermatozoa viability, motility, fertilising ability and morphology were measured.

4. In Experiment 1, spermatozoa viability and morphology were adversely affected after storage (P?M/l [K+] whereas spermatozoa motility decreased as [K+] increased from 12·5 to 80?mM/l.

5. In Experiment 2, during storage at 5°C, the spermatozoa viability was comparable among any of the diluents (standard or modified) but morphology was better (P? 6. In Experiment 3, after 48?h of storage in a diluent containing 40?mM/l of [K+], the spermatozoa functions were better preserved at 10°C than at 5 or 20°C.

7. It is concluded that a higher than physiological level of potassium can be used in a diluent without detrimental effect on emu spermatozoa survival during 48?h storage and that the best outcome was with storage at 10°C rather than 5 or 20°C.  相似文献   

4.
The objective was to assess the effect of cooling to different subzero temperatures around ice formation (?5°C) on dog sperm cryosurvival and plasma membrane fluidity. Semen was centrifuged, and sperm were resuspended in a Tris‐egg yolk medium (3% glycerol). Diluted sperm were cooled from 22 to 5°C, and then, a Tris‐egg yolk medium containing 7% glycerol was added (final concentration of 5% glycerol and 200 × 106 cells/ml). Sperm were packaged in 0.5‐ml plastic straws, and equilibration was done 16 hr at 5°C before freezing. I. Straws (n = 47) at 5°C were exposed to nitrogen vapours to determine the freezing point. II. Other straws (from different ejaculates) processed as mentioned, were further cooled to ?3, ?5 or ?7°C and immediately rewarmed in a water bath at 37°C. Motility, plasma membrane functionality and acrosome integrity were assessed. III. Other straws (from different ejaculates) processed as mentioned were further cooled to ?3 or ?5°C, frozen over nitrogen vapours and stored in liquid nitrogen for one month. Straws were thawed in a water bath at 38°C for 30 s. Motility, plasma membrane functionality, plasma membrane integrity, acrosome integrity, capacitation status and plasma membrane fluidity were assessed. Ice nucleation temperature was ?14.3 ± 2.05°C (mean ± SD); cooling to +5, ?3, ?5 and ?7°C, without freezing, produces no differences on sperm quality between target temperatures; cooling to +5, ?3, and ?5°C produced no differences on sperm survival and plasma membrane fluidity after freeze–thawing. In conclusion, cooling of dog spermatozoa to different subzero temperatures did not improve sperm cryosurvival and had no effect on plasma membrane fluidity after thawing.  相似文献   

5.
There is need for standardization of freezing–thawing protocol for rooster semen to minimize variability among results. Therefore, we aimed to compare effect of four different permeating cryoprotectants and two thawing temperatures (37 vs. 5°C) on sperm post‐thaw motility and to analyse combined effect of the best permeating cryoprotectant (P‐CPA) with one of four non‐permeating cryoprotectants (N‐CPA) on post‐thaw quality of rooster semen evaluated in vitro. Pooled semen from Ross PM3 rooster heavy line was diluted in Kobidil extender and frozen in cryoprotectant solution containing 6% dimethylacetamide, 7.5% dimethylformamide, 9% N‐methylacetamide or 8% ethylene glycol (EG) in liquid nitrogen vapours. To determine the best thawing rate, straws were thawed either at 37 or 5°C. Furthermore, samples were frozen in the presence of the best N‐CPA either with 0.75 mol/L ficoll, 0.2 mol/L sucrose, 0.2 mol/L trehalose or 0.05 mol/L glycine. Sperm motility, membrane destabilization and viability were analysed to compare different freezing–thawing conditions. In addition, morphology and ultrastructure analysis were performed to compare fresh and frozen‐thawed sperm quality. Our results indicate that the combination of EG and the thawing at 5°C improves (p ≤ .05) sperm post‐thaw motility. Moreover, ficoll addition to EG‐based freezing extender provided additional beneficial effect (p ≤ .05) on progressive movement and apoptosis incidence. Further work should evaluate different N‐CPA concentrations to improve freezing protocol. In addition, fertility evaluation and testing on different chicken lines are needed in order to contribute to animal genetic resources bank.  相似文献   

6.
The interaction between nine lactic acid bacteria (LAB) and five yeast strains isolated from airag of Inner Mongolia Autonomic Region, China was investigated. Three representative LAB and two yeasts showed symbioses were selected and incubated in 10% (w/v) reconstituted skim milk as single and mixed cultures to measure viable count, titratable acidity, ethanol and sugar content every 24 h for 1 week. LAB and yeasts showed high viable counts in the mixed cultures compared to the single cultures. Titratable acidity of the mixed cultures was obviously enhanced compared with that of the single cultures, except for the combinations of Lactobacillus reuteri 940B3 with Saccharomyces cerevisiae 4C and Lactobacillus helveticus 130B4 with Candida kefyr 2Y305. C. kefyr 2Y305 produced large amounts of ethanol (maximum 1.35 g/L), whereas non‐lactose‐fermenting S. cerevisiae 4C produced large amounts of ethanol only in the mixed cultures. Total glucose and galactose content increased while lactose content decreased in the single cultures of Leuconostoc mesenteroides 6B2081 and Lb. helveticus 130B4. However, both glucose and galactose were completely consumed and lactose was markedly reduced in the mixed cultures with yeasts. The result suggests that yeasts utilize glucose and galactose produced by LAB lactase to promote cell growth.  相似文献   

7.
This study investigated the effects of skim milk on the quality and fertility of boar spermatozoa under long‐term chilled preservation. Semen samples were stored in Modena solution supplemented with 0 (control) to 50 mg/mL skim milk at 5°C for 4 weeks; spermatozoa stored with 7.5 and 15 mg/mL of skim milk (7.5‐SM and 15‐SM groups, respectively) exhibited significantly higher motility indices than those of the control group up to 3 weeks (P < 0.05), and the 7.5‐SM group showed improved motility indices even after 4 weeks (P < 0.05). In vitro fertilization using spermatozoa in the 7.5‐SM and 15‐SM groups stored at 5°C for 2 weeks showed significantly higher fertilization rates of spermatozoa and the development rates to blastocyst than the control group (P < 0.05), and the 7.5‐SM group showed similar rates of fertilization and blastocyst formation in the fresh non‐stored spermatozoa group. After artificial insemination using spermatozoa stored for 2 weeks in the 7.5‐SM group, healthy piglets were obtained. Boar spermatozoa can be stored at 5°C in a Modena solution containing skim milk. Supplementation of 7.5 mg/mL skim milk improves boar spermatozoa motility and fertility even after liquid preservation at 5°C for 2 weeks.  相似文献   

8.
Little is known about the analgesic action of buprenorphine (BUP) in cats. Relative to man, the cat has a more alkaline oral pH, which may make this an effective route for administering BUP in this species. This study aimed to assess and compare the pharmacokinetics and pharmacodynamics of sublingual (S‐L) and IV administration of BUP. Thermal threshold (TT) was measured and blood samples were collected following IV or S‐L administration (20 µg kg?1) of the injectable formulation. Six cats (five spayed females, one castrated male, 4.1–6.6 kg) were used. Each cat received both treatments in a randomized cross‐over study design with 1 month between experiments. Twenty‐four hours prior to each study, the lateral thorax of each of the cats was shaved, cephalic and jugular catheters placed, and oral pH measured. On the day of the study, TT was measured using a ‘thorax‐mounted’ thermal threshold‐testing device specifically developed for cats. The cats were free to move around. Skin temperature was recorded before each test, then the heater activated. When the cat responded by flinching, turning, or jumping, the stimulus was terminated and the threshold temperature was recorded. The thermal threshold cut‐off point was 55.5 °C. Three baseline thresholds were recorded before treatment with S‐L or IV (via cephalic catheter) BUP (20 µg kg?1). Blood was withdrawn (jugular) at 1, 2, 4, 6, 10, 15, 30, 45, 60 minutes and at 2, 4, 6, 8, 12, and 24 hours post‐administration. TT was measured every 30 minutes?6 hours, 1–12 hours, and at 24 hours post‐administration. Plasma was immediately separated, stored at ?20.5 °C, and assayed within 4 months using a commercially available 125I radioimmunoassay. Threshold data were analyzed using anova with a repeat factor of time. No adverse effects were noted. Pupils were dilated for up to 9 hours post‐BUP. Behavioral changes were calm euphoria. Measured oral pH was 9 in each cat. Pre‐treatment mean threshold (±SD) was 41.2 ± 0.9 °C in the S‐L group and 40.8 ± 0.85 °C in the IV group. There were no significant differences between the groups with respect to thresholds over time (p = 0.72). Thresholds were significantly increased from 30 to 360 minutes in both the groups (>44.615 °C). Peak plasma BUP (Cmax) was lower (11 ± 6.7 ng mL?1vs. 92.9 ± 107.9 ng mL?1) and occurred later (Tmax) (30 minutes vs. 1 minute) after S‐L compared to IV administration, respectively. BUP (20 µg kg?1)‐administered S‐L or IV provided antinociception between 30 and 360 minutes after administration. Plasma levels did not correspond to TT.  相似文献   

9.
The aim of this study was to determine the most efficient vitrification protocol for the cryopreservation of day 7 in vitro produced (IVP) porcine blastocysts. The post‐warm survival rate of blastocysts vitrified in control (17% dimethyl sulfoxide + 17% ethylene glycol [EG] + 0.4 mol/L sucrose) and commercial media did not differ, nor did the post‐warm survival rate of blastocysts vitrified in medium containing 1,2‐propandiol in place of EG. However, vitrifying embryos in EG alone decreased the cryosurvival rate (55.6% and 33.6%, respectively, p < .05). Furthermore, the post‐warm survival rates of blastocysts vitrified with either trehalose or sucrose as the non‐penetrating cryoprotectant did not differ. There was also no significant difference in post‐warm survival of blastocysts vitrified in control (38°C) media and room temperature (22°C) media with extended equilibration times, although when blastocysts were vitrified using control media at room temperature, the post‐warm survival rate increased (56.8%, 57.3%, 72.5%, respectively, p < .05). The findings show that most cryoprotectant combinations examined proved equally effective at supporting the post‐warm survival of IVP porcine blastocysts. The improved post‐warm survival rate of blastocysts vitrified using media held at room temperature suggests that the cryoprotectant toxicity exerted in 22°C media was reduced.  相似文献   

10.
The present work studied different spermatozoa parameters and the ability of frozen rabbit spermatozoa to fertilize, in vitro, in vivo‐matured oocytes, as a test to predict their in vivo fertility and prolificacy. Semen from rabbit bucks was frozen using two freezing protocols [in a freezer at ?30°C or in liquid nitrogen vapour (LNV)]. For the in vivo trial, females were inseminated with frozen‐thawed spermatozoa. Oocytes used for in vitro testing were recovered 14 h after ovulation induction from donors and co‐incubated with 2 × 106 frozen‐thawed spermatozoa during 4 h at 37°C in Tyrode's medium under an atmosphere of 5% CO2 in air with maximal humidity. After co‐incubation period, presumptive zygotes were cultured in TCM199 supplemented with 20% foetal bovine serum (FBS), under the same conditions described above. Although no statistical differences were observed between freezing protocols in seminal parameters [motility rate: 40 and 35%, VCL: 35 and 46 μm/s, amplitude of lateral head displacement (ALH): 1.7 and 2.4 μm, for semen frozen at ?30°C and in LNV, respectively], significant differences were noted in the fertilizing ability in vivo and in vitro. Semen frozen at ?30°C showed the highest fertilizing ability in vitro (26.7% vs 6.2 and 8.7% for semen frozen at ?30°C, in LNV and fresh semen, respectively) and the lowest fertility rate in vivo (21.7% vs 64.2% and 70.6% for semen frozen at ?30°C, in LNV and fresh semen, respectively). Sperm frozen at ?30°C seemed to be more capacitated.  相似文献   

11.
Background: D‐dimer measurement in dogs is considered the most reliable test for detecting disseminated intravascular coagulation or thromboembolism. Objectives: The purposes of this study were to compare 2 D‐dimer assays, a quantitative immunoturbidimetric and a semiquantitative latex agglutination assay, and to assess the effect of hemolysis and storage conditions on D‐dimer concentration using the quantitative assay. Methods: The immunoturbidimetric assay was validated using canine citrated plasma samples containing different concentrations of D‐dimer. The effect of storage at various temperatures and times was assessed. Hemolysis was produced by adding lysed RBCs to the samples for a final hemoglobin concentration of 0.35 g/dL. Results: For clinically relevant values (>250 μg/L), intra‐assay and interassay coefficients of variation were 6.8% and 7.2%. The assay was linear (r2=1.00), and the tests had good agreement (κ=0.685, P<.001). Storage at 4 °C and ?20 °C and hemolysis had no significant effect on D‐dimer concentrations. In hemolyzed samples stored at room temperature for ≥48 hours, fine clots were noted and often resulted in falsely increased D‐dimer concentrations. Conclusions: Our findings suggest that the immunoturbidimetric assay validated in this study is reliable and accurate for the measurement of D‐dimer in canine plasma. Samples can be stored for up to 1 month at ?20 °C and moderate hemolysis does not significantly affect the D‐dimer concentration in frozen or refrigerated samples.  相似文献   

12.
1. Vacuum packaging and gas packaging (CO2:N2; 1:9 or 2:8) gave useful extensions to the shelf‐lives of both breast and leg and thigh portions of chicken.

2. Extension of shelf‐life was more marked at 1 °C than at 4 to 5 °C and with breast portions rather than leg and thigh portions.

3. Psychrotrophic Enterobacteriaceae were more likely to be a problem at the higher storage temperature on breast portions and Alteromonas putrefaciens on leg and thigh portions.

4. Lactic acid and potassium sorbate pre‐treatments were of value in controlling multiplication of Alt. putrefaciens on leg and thigh portions.

  相似文献   

13.
The aim of this study was to investigate the effects of different concentrations of glutathione in Modena on boar sperm quality during liquid storage at 17°C. Boar semen samples were collected and diluted with Modena containing different concentrations (0, 1, 5, 10, 15 mmol/L) of glutathione. Sperm motility, effective survival period, plasma membrane integrity, acrosome integrity, total antioxidant capacity (T‐AOC) activity, malondialdehyde (MDA) content and hydrogen peroxide (H2O2) content were measured and analyzed. The results showed that Modena supplemented with 1, 5 and 10 mmol/L glutathione improved sperm motility, effective survival period, plasma membrane integrity and T‐AOC, and decreased MDA content and H2O2 content. Meanwhile, the semen sample diluted with Modena containing 1 mmol/L glutathione achieved optimum effect, and effective survival period was 6.1 days. After 5 days preservation, sperm motility, plasma membrane integrity and T‐AOC of the group treated with 1 mmol/L glutathione were all higher than that of other groups. Meanwhile, MDA content and H2O2 content were lower than that of other groups. In conclusion, Modena supplemented with glutathione decreased the oxidative stress and improved the quality of boar semen during liquid storage at 17°C, and 1 mmol/L concentration was the optimum concentration. © 2016 Japanese Society of Animal Science  相似文献   

14.
The effects of organic acids on the microbial quality of Taiwanese‐style sausages were studied. Pork meat from a Taiwan retail market was decontaminated with various organic acids (citric, lactic and tartaric acid), then, the raw meat was used to make Taiwanese‐style sausages and stored from 0 to 40 days at 4°C. The total plate counts, lactic acid bacteria, Micrococcus, Listeria monocytogenes, Hunter‐L and Hunter‐a values were determined. The total plate counts of the control group were initially greater than those of the treated groups. Higher incidence rates of L. monocytogenes in the products were obtained from the control group, but were not detected in the treated groups during storage. Lactic acid bacteria counts following the lactic acid treatment were lower than those of the other groups. Micrococcus counts of the controls increased by 0.6–1.2 log10 colony‐forming unit (CFU)/g greater than those of treated groups throughout storage at 4°C. The light color (L‐value) of the control group gradually decreased during storage. Pork meat dipped in various organic acids was found to be suitable to extend the shelf‐life and improve the microbiological quality of Taiwanese‐style sausages.  相似文献   

15.
Topical compounded Timentin® diluted with an inactive vehicle has been reported to be effective in the treatment of otitis externa caused by Pseudomonas aeruginosa. The aims of this study were to determine the biological efficacy of Timentin® (ticarcillin and clavulanic acid) when diluted in the carrier vehicle Methopt® against P. aeruginosa and to determine the efficacy and stability of Timentin® aqueous stock concentrate solution. Timentin® stock concentrate was tested against four P. aeruginosa isolates on days 0, 7, 14, 21 and 28; then after 2, 3, 4, 5, 6, 9 and 12 months of storage at 4 or ?20°C. The diluted Timentin®–Methopt® solutions were tested against all isolates after 0, 2, 4, 6, 8, 10, 12, 14, 17, 21, 24 and 28 days of storage at 24 or 4°C. Minimal inhibitory concentration (MIC) levels for all strains were determined using the broth microdilution method. The MIC of the stock solution remained relatively constant and acceptable throughout the study when stored at ?20°C and was also acceptable for shorter time periods (6–9 months) when stored at 4°C. The MIC for the diluted Timentin®–Methopt® solution remained relatively constant and acceptable throughout the study for all four bacterial strains, with no difference between the solutions stored at 4 or 24°C. The results of this study indicate that storage of the Timentin® stock solution at ?20°C does not compromise efficacy for at least 12 months and that Timentin® diluted in Methopt® was stable for 28 days when stored at either 4 or 24°C.  相似文献   

16.
This study was designed to compare the quality of liquid‐stored buffalo bull spermatozoa in soya lecithin based extender Bioxcell® (BIOX), milk (MILK), tris‐citric egg yolk (TEY) and egg yolk‐citrate (EYC) extender at 5°C. Semen was collected from five Nili‐Ravi buffalo (Bubalus bubalis) bulls of 6–7 years of age with artificial vagina over a period of 3 weeks (two consecutive ejaculates once in a week). Semen ejaculates having more than 60% motility were pooled, split into four aliquots, diluted (37°C; 10 × 106 motile spermatozoa/ml), cooled from 37 to 5°C in 2 h (0.275°C/min) and stored for 5 days. Sperm motility, viability, plasma membrane integrity (PMI) and normal acrosomal ridge were studied at first, third and fifth day of storage. Higher values of progressive sperm motility (%), sperm viability (%), sperm PMI (%) and normal apical ridge (%) were observed in BIOX, MILK and TEY extenders at first, third and fifth day of storage than EYC extender. Progressive sperm motility, sperm viability and sperm PMI in BIOX® extender were not different from MILK and TEY extenders at 1st and third day storage period. However, at fifth day of storage, the values for these parameters remained significantly higher (p < 0.05) in BIOX® compared with MILK, TEY and EYC extenders. At fifth day of storage, the semen quality parameters for Bioxcell® were comparable to those with MILK and TEY extenders at third day of storage. In conclusion, motility, viability and PMI of buffalo bull spermatozoa remained similar in Bioxcell®, milk and TEY extender at first and third days of storage at 5°C. Yet, the values for the aforementioned parameters in Bioxcell® were higher compared with milk, TEY and EYC extender at fifth day of storage at 5°C.  相似文献   

17.
A feeding trial of 70‐days was carried out to study the haemato‐immunological and stress responses of Labeo rohita fingerlings reared at two water temperatures [ambient (Amb) – 27 °C and 32 °C] fed with graded levels of gelatinized corn carbohydrate (GC). Two hundred and sixteen fingerlings were randomly distributed into six treatment groups in triplicate. Three semi‐purified diets were prepared containing 30% crude protein with graded levels of GC 40%, 50% and 58%. The six treatment groups were T1 (40% GC × Amb), T2 (40% GC × 32 °C), T3 (50% GC × Amb), T4 (50% GC × 32 °C), T5 (58% GC × Amb) and T6 (58% GC × 32 °C). The blood glucose level was significantly (p < 0.05) lowered in groups fed with 58% GC level. Neither dietary GC levels nor temperature had a significant (p > 0.05) effect on serum cortisol and superoxide dismutase activity. Lysozyme activity was significantly higher (p < 0.05) in T1 during pre‐ and post‐challenge period while temperature alone had a significant (p < 0.05) effect on post‐challenge Nitroblue Tetrazolium and found higher at 32 °C. A significant effect of GC levels and rearing temperature was recorded on WBC in the pre‐ and post‐challenge period. Highest pre‐challenge WBC was observed in T4 group and in the post‐challenge period T1 group recorded maximum. Water temperature had significant effect on pre‐challenge haemoglobin content, highest being at 32 °C (T2). A significant (p < 0.05) effect of rearing temperature and dietary GC level on total serum protein and albumin was also observed. Highest total serum protein and albumin was recorded in T1 and globulin in T2. Percentage survival after challenging with Aeromonas hydrophila was highest in T1 followed by T3 group and lowest in T6. The results obtained in the present study suggest that L. rohita fingerlings may utilize higher levels of dietary GC at higher temperature (32 °C) but may affect its immunity status.  相似文献   

18.
In order to clarify the ensiling characteristics of stylo (Stylosanthes guianensis Swartz), the effects of wilting (no wilting, light wilting and heavy wilting) and storage temperatures (10°C, 20°C, 30°C and 40°C) on the fermentation quality and aerobic stability of stylo silage were investigated. Wilting had no significant influence on the contents of crude protein, ether extract and acid detergent fiber, and numbers of lactic acid bacteria, aerobic bacteria, yeasts and mold (P > 0.05). Heavy wilted material, wilted for 12 h, had higher neutral detergent fiber content and lower water‐soluble carbohydrate content than unwilted and light wilted materials (P < 0.05). Wilting and storage temperatures had significant effects on pH value, acetic acid, butyric acid and NH3‐N contents of stylo silage (P < 0.01 or P < 0.05). Wilting tended to reduce acetic acid and NH3‐N contents and improve the fermentation quality of stylo silage. In all the silages, no wilting silage ensiled at 30°C had the highest butyric acid content (P < 0.05). High temperature of 40°C markedly restricted the growth of lactic acid bacteria and aerobic bacteria in silage, irrespective of wilting. The wilted silage or silage stored at low temperature had poor aerobic stability.  相似文献   

19.
The pharmacokinetics and tissue residues of moroxydine hydrochloride were studied in gibel carp at water temperature of 15 and 25 °C. Samples (blood, skin, muscle, liver, and kidney) were collected over 10 days after the treatment and analyzed by high‐performance liquid chromatography with an ultraviolet detector. The results indicated that the influence of water temperature on the metabolism of the drug was significant. The plasma concentration–time data of moroxydine hydrochloride conformed to single‐compartment open model at the two water temperatures. There were higher absorption rate (t1/2ka) and longer elimination half‐lives (t1/2ke) at 15 °C (4.29 and 15.87 h, respectively) compared with those at 25 °C (3.02 and 4.22 h, respectively). The maximum plasma concentration (Cmax) and the time‐point of maximum plasma concentration (Tp) were 2.98 μg/mL and 10.35 h at 15 °C and 3.12 μg/mL and 4.03 h at 25 °C, respectively. The distribution volume (Vd/F) of moroxydine hydrochloride was estimated to be 4.55 L/kg at 15 °C and 2.89 L/kg at 25 °C. The total body clearance (CLb) of moroxydine hydrochloride was determined to be 0.25 and 0.49 L/(h·kg) at 15 °C and 25 °C, respectively; the areas under the concentration–time curve were 75.89 μg·h/mL at 15 °C and 42.33 μg·h/mL at 25 °C. The depletion of moroxydine hydrochloride in gibel carp was slower with a longer half‐life period, especially at lower water temperature that was tested.  相似文献   

20.
The effects of concentrations of glycerol, ethylene glycol or dimethylsulphoxide (DMSO) in the presence of either 0.25 M lactose or sucrose on the post-thaw survival of mouse quickly-frozen compacted morulae were studied. In this method, the embryos were directly frozen in liquid nitrogen (LN2) vapor at approximately -170 degrees C for 2 min before being plunged into LN2. High survival rates of frozen-thawed embryos were obtained when the freezing medium contained 3 M ethylene glycol with either 0.25 M lactose or sucrose (76.5 and 70.2%, respectively). When the embryos were frozen in glycerol, significantly high survival was obtained with 3 M glycerol + 0.25 M sucrose (73.5%, P less than 0.001). However, a freezing medium containing DMSO with either sugar gave lower survival rates. At a higher concentration of 4 M, ethylene glycol with 0.25 M lactose gave significantly higher survival rate than glycerol or DMSO (P less than 0.05). Significantly higher rates were obtained at 2 M with all 3 cryoprotectants when the freezing medium contained lactose rather than sucrose (P less than 0.05). This study showed that glycerol and ethylene glycol were effective cryoprotectants in the quick freezing of mouse embryos, while DMSO was less effective. In addition, the protective effects of these cryoprotectants are affected by their concentrations and the type of sugar used.  相似文献   

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