首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 53 毫秒
1.
The present preclinical study was performed to investigate the pharmacokinetics of flumequine in Atlantic salmon (Salmo salar L.) in seawater after administration of different doses and dosage formulations. Flumequine was administered intravenously (dose 4.9 mg/kg fish) and orally from the drug delivery system Aqualets as Apoquin 5 g/kg (dose 25 mg/kg) and 10 g/kg (dose 50 mg/kg), respectively. Experiments were carried out with oxolinic acid administered in the same way for the purpose of comparing the two compounds. The seawater temperature was 5±0.2°C in all experiments.

The pharmacokinetic calculations showed that the distribution half-life for flumequine was and for oxolinic acid . The drugs were absorbed rapidly, and flumequine reached a plasma concentration of Cmax = 2.26 μg/ml after a single oral dose of 25 mg/kg, whereas oxolinic acid reached Cmax = 0.99 μg/ml. The apparent bioavailability of flumequine was found to be 40–45%, whereas the apparent bioavailability of oxolinic acid varied from 25% at a dose of 50 mg to 40% at a dose of 25 mg/kg body weight of fish. The distribution profile of flumequine in the various compartment of fish appeared to be different from that of oxolinic acid. After a single oral dose (25 mg/kg) the areas under the concentration-time curves showed that flumequine was 2.3 times more concentrated in plasma and 2.6 times more concentrated in liver compared to oxolinic acid. In muscle the difference was less pronounced, flumequine being 1.4 times more concentrated than oxolinic acid.  相似文献   


2.
土霉素在鳗鲡组织中残留的消除规律   总被引：32，自引：1，他引：32       下载免费PDF全文
李美同 《水产学报》1997,21(1):39-43
  相似文献   

3.
An experiment was carried to determine the plasma fenbendazole (FBZ) concentration and physio‐metabolic responses in juveniles of Labeo rohita (90 ± 4 g) after oral administration of single doses at 10, 20 and 50 mg, 20 mg FBZ/kg b.wt. in multiple times on 1st, 3rd and 7th day. The blood samples were collected at 0.5, 1, 2, 4, 8, 12, 24, 30, 48, 72, 96 and 120 hr, after single‐dose administration, and regularly (upto 15 day) in multiple dose. Plasma FBZ concentration was determined up to the limit of detection (LoD) of 0.09 µg/ml by HPLC. There was no parent drug detected in plasma for administration of 10 mg FBZ/kg b.wt. The drug attained the peak concentration (Cmax) 1.85 and 3.09 µg/ml in plasma at 4 hr (Tmax) after administration of 20 and 50mg FBZ/kg b.wt. respectively. Plasma FBZ was detectable up to 96 and 120 hr with concentration 0.09 ± 0.007 and 0.098 ± 0.006 µg/ml, respectively, after single‐dose administration of 20 and 50mg/kg b.wt. In case of multiple‐dose administration, the maximum concentration of FBZ was 1.01 ± 0.03 µg/ml on 7th day that was less than to the single dose at 50 mg/kg b.wt. However, FBZ was detected up to 11 day after multiple doses. The study revealed that the hepatic antioxidant enzymes activities like superoxide dismutase, catalase and glutathione‐S‐transferase were significantly affected by increasing FBZ in single and multiple doses. The results of the present study could reveal that single‐ or multiple‐oral administration of FBZ at 20 mg/kg b.wt. in feed as antihelminthic drug in L. rohita could be considered as the safe dose.  相似文献   

4.
The influence of different modes of feeding on the bioavailability of orally administered chlortetracycline was studied in weaned pigs. The animals were divided into three groups receiving a dry, a moist or a soup diet, respectively. CTC was applied at a concentration of 6000 ppm and 2500 ppm to each diet and the oral dosage of CTC was 40 mg chlortetracycline/kg bodyweight. The results of the experiments show that the pharmacokinetics of orally applied chlortetracycline are significantly influenced by the mode of feeding. A significantly higher bioavailability was observed with soup feeding compared with moist or dry food. To achieve a therapeutic blood level of 0.5-1.5 micrograms chlortetracycline/ml blood, 20-30 mg chlortetracycline/kg bodyweight/12 h and 30-40 mg chlortetracycline/kg bodyweight/12 h should be applied to soup and dry or moist feed, respectively.  相似文献   

5.
The concentrations of dexamethasone and prednisolone in the plasma of pigeons are measured by radioimmunoassay. The plasma curves show a more rapid ascent and steeper descent after dexamethasone injection (1 mg, 2 mg, 4 mg and 10 mg/kg of body weight IM) than after prednisolone injection (3 mg, 5 mg, 10 mg and 50 mg/kg of body weight IM). The longer-lasting effect after prednisolone injection could likewise be seen in the white blood count. The immunosuppressive effect of glucocorticoid preparations especially should be considered when applying antibiotics.  相似文献   

6.
Biological actions of atrial natriuretic factor in flatfish   总被引：1，自引：0，他引：1  
Flounder adapted to seawater were chronically cannulated and received a single i.v. injection of either saline (control) or 10 µg/kg b.w. of human ANF. Compared to controls, ANF significantly reduced (p<0.001) mean arterial blood pressure; full recovery was evident after 4 hours. Blood samples taken at intervals after saline or ANF injection showed that ANF caused a marked increase of 33.7 µg/100 ml in plasma cortisol concentration (p<0.001) 5 hours post injection. The rate of recovery of22Na in seawater after a single i.v. injection of 14×106 cpm/kg22NaCl was significantly increased (p<0.01) following ANF injection compared to controls suggesting that ANF stimulates Na+ efflux. This observation was confirmed in plaice and dab. The steroidogenic action of ANF and its ability to promote Na+ efflux are discussed in relation to its potential osmoregulatory role in teleost fish.  相似文献   

7.
The pharmacokinetics of racemic phenprocoumon were studied in 8 adult horses after the single intravenous and oral administration of 0.75 mg/kg. After i.v. administration the plasma concentration of phenprocoumon showed a biphasic decline in time. The pharmacokinetics were calculated on the two-compartment open model. The average plasma half-life (beta-phase) was 22 hours, the apparent volume of distribution was 0.61 l/kg, Cltot was 25.2 ml/kg/h (13.9-40.9 ml/kg/h). The systemic bioavailability of oral phenprocoumon was 97.6%, Tmax was found to be 4-12 hours. The effect of phenprocoumon on the coagulation system was determined by the activity of Factor X, the Quick's one stage prothrombin time and the PTT. Factor X showed the most marked effect. A reduction of the content of Factor X was seen over 7-9 days, it decreased to 11-33%. Quick's one stage prothrombin time was reduced over 4-8 days, the lowest values were 22-55%. The PTT showed only a small reaction on the single administration of 0.75 mg/kg phenprocoumon. Differences in the effect on the coagulation between the i.v. and the oral administration could not be observed. In comparison to warfarin, phenprocoumon showed a longer t0.5 (beta) and produced a markedly longer hypothrombogenic reaction. Therefore phenprocoumon appeared to be more suitable for a long term anticoagulation therapy in horses than the structurally related warfarin.  相似文献   

8.
研究了不同水温(16℃、25℃)、不同给药剂量(10 mg/kg、20 mg/kg)和不同给药方式(肌注、口灌)等条件下,恩诺沙星及其代谢产物环丙沙星在中华绒螯蟹体内的药代动力学,比较了不同条件下药物在蟹血淋巴中的吸收、分布和代谢的差异。结果表明,恩诺沙星在蟹血淋巴中的药-时数据符合开放式二室模型。16℃时以10 mg/kg剂量肌注给药后,恩诺沙星在蟹血淋巴的主要药代动力学参数为:AUC96.818 mg/(L.h),Cmax6.54μg/mL,t1/2α0.851 h,t1/2β95.415 h;25℃时以10 mg/kg剂量肌注给药后,恩诺沙星的主要药代动力学参数为:AUC168.457 mg/(L.h),Cmax7.12μg/mL,t1/2α0.58h,t1/2β88.833 h;25℃时以20 mg/kg剂量肌注给药后,恩诺沙星的主要药代动力学参数为:AUC155.612 mg/(L.h),Cmax11.045μg/mL,t1/2α5.239h,t1/2β88.378 h;25℃时以10 mg/kg剂量口灌给药后,恩诺沙星的主要药代动力学参数为:AUC86.525 mg/(L.h),Cmax3.469μg/mL,t1/2α8.071h,t1/2β61.842 h。不同条件下,恩诺沙星在蟹血淋巴中的主要药代动力学参数差异较大。恩诺沙星的活性代谢产物环丙沙星在各种给药条件下的蟹血淋巴中均能检出,但含量均处于较低值,且药-时数据不能用房室模型拟合,表明恩诺沙星在蟹体内只有极少部分代谢为环丙沙星。  相似文献   

9.
T‐2 toxin is a mycotoxin produced by several Fusarium fungi that can contaminate plant components used in feed for aquaculture. The aim of this 28‐day study was to investigate the effect of the T‐2 toxin in feed in concentrations 1.0 and 1.8 mg/kg (0.01 mg/kg b.w. and 0.018 mg/kg b.w.) on the oxidative stress markers and on the detoxifying enzymes of the rainbow trout. The results showed that T‐2 toxin in both tested concentrations induced oxidative stress and antioxidant defence in the liver of trout manifesting by the increase in activities of enzymes glutathione‐S‐transferase, glutathione reductase and glutathione peroxidase and the decrease in the catalase activity. The increase in lipid peroxidation was recorded only in the higher concentration of T‐2 toxin. Ceruloplasmin activity in the plasma increased at both tested concentrations, and the ferric reducing ability of the plasma increased at the higher toxin concentration. The T‐2 toxin in feed caused alteration of the total protein, albumin and triacylglycerols as well as the alkaline phosphatase activity in the plasma. Despite no changes in histological examination were found, the influence of T‐2 toxin on scavenger system may result in increased sensitivity to other stress factors.  相似文献   

10.
Twenty-five heifers and cows with follicular cysts (high level of total oestrogens, low level of progesterone in plasma) were treated with 20 or 50 micrograms buserelin i.m. 5-84 weeks after parturition. Two hours after medication an increased LH release was observed in all animals. In contrast to LH, FSH concentration was not increased in all cows. Twelve days after treatment a high progesterone concentration in plasma could be determined in 17 of 25 treated animals. Twenty cows showed oestrous symptoms 23.5 +/- 9.6 days after medication. The oestrous cycle was prolonged in 10 cows. Nineteen cows were inseminated and 14 cows became pregnant after 1-4 (phi 1.7 +/- 0.9) inseminations (73.6% of all inseminated cows and 56% of all treated cows). The differences in conception rate and in services per conception after treatment with 20 or 50 micrograms buserelin in favour of the higher dosage cannot be attributed to the medication.  相似文献   

11.
磺胺甲基异噁唑在大菱鲆体内的代谢动力学研究   总被引：2，自引：0，他引：2       下载免费PDF全文
采用高效液相色谱法测定血浆、肌肉和肝脏中的磺胺甲基异噁唑含量,通过3P97药动学软件对磺胺甲基异噁唑在大菱鲆体内的药代动力学规律进行了分析研究。研究结果表明,在（11±1）℃水温条件下,单次口灌100mg／kg磺胺甲基异噁唑（SMZ）,SMZ在大菱鲆肌肉、肝脏和血浆中的代谢过程均符合一级吸收一室模型。大菱鲆肌肉、肝脏和血浆中药物浓度分别在给药后11．89、10．53和4.87h达到最大值,Cmax分别为21．52、5．35和44．07mg／kg,给药后5、6d和72h含量低于最大残留限量（0．1mg／kg）,18、24和10d后SMZ未检出（〈0．01mg／kg）。  相似文献   

12.
Abstract. The kinetics of gentamicin and tobramycin in juvenile brown sharks, Carcharhinus plumbeus (Nardo), were studied using a commercially available radioimmune assay (Clinical Assays, Cambridge, Massachusetts). Preliminary recovery studies in vitro demonstrated 95% recovery of antibiotic spiking with no detection of interfacing substances. There were no differences between serum and plasma data using this assay. Both drugs demonstrated distinct two-compartment characteristics. The mean half-life of the alpha component was 5.4±1.0 h for gentamicin and 3.2±0.5 h for tobramycin. The half-lives of the beta components were markedly longer, 54±4.9 h for gentamicin and 48±2 h for tobramycin. The experimental designs could not exclude third compartments. A therapeutic dosage schedule for gentamicin of 2 mg/kg intramuscularly followed by 1 mg/kg at 8 and 72 h was tested. This schedule avoided plasma levels greater than 12μg/ml and troughs greater than 2 μg/ml but more frequent administration may be required to treat infections with bacteria which are less sensitive to aminoglycoside antibiotics. A therapeutic tobramycin schedule of 2.5 mg/kg intramuscularly followed by 1.0 mg/kg, 4 h later and daily thereafter, achieved plasma levels within the human therapeutic range (5.8μg/ml) on the second day of therapy. Levels considered toxic to humans were not reached for 5 days.  相似文献   

13.
The pharmacokinetics of oxolinic acid and oxytetracycline were examined in kuruma shrimp (Penaeus japonicus) after intra-sinus (10 and 25 mg/kg, respectively) and oral (50 mg/kg) administration. The shrimp were kept in tanks with recirculated artificial seawater at a salinity of 22–23 ppt. The water temperature was maintained at 25±0.6 °C. The hemolymph concentrations of both drugs after intra-sinus dosing were best described by a two-compartment open model. The distribution and elimination half-lives (t1/2 and t1/2β) were found to be 0.59 and 33.2 h for oxolinic acid and 0.45 and 24.7 h for oxytetracycline, respectively. The apparent volume of distribution at a steady state (Vss) and total body clearance (CLb) were estimated to be 1309 ml/kg and 28.8 ml/kg/h for oxolinic acid and 748 ml/kg and 22.7 ml/kg/h, respectively. The hemolymph concentration–time curves after oral administration did not fit by the nonlinear least squares method using one- and two-compartment model with first-order absorption in either of the drugs. The peak hemolymph concentration (Cmax), the time to peak hemolymph concentration (tmax) and the elimination half-life were found to be 17.8 μg/ml, 7 h and 34.3 h for oxolinic acid and 24.3 μg/ml, 10 h and 33.6 h for oxytetracycline, respectively. The bioavailability (F) after oral administration was 32.9% for oxolinic acid and 43.2% for oxytetracycline. The hemolymph protein binding in vivo was determined to be 36.7±8.5% for oxolinic acid and 22.9±4.8% for oxytetracycline.  相似文献   

14.
In a collection of newborn calves including DRB, DSB and DFV breeds (n = 27) the plasma Selenium concentration was measured directly after parturition up until six weeks after parturition by means of neutron-activating analysis. Minimal Selenium concentration occurred on the fourth day. The values of the subsequent Selenium concentrations exceeded those immediately after parturition only slightly. The tested group could be divided into two subgroups, one of which consisted of calves with extremely low initial Selenium concentrations, whereas the animals in the others showed high levels immediately after parturition (0.019 +/- 0.004 micrograms/ml versus 0.046 +/- 0.010 micrograms/ml of plasma). The diagrams appeared to be parallel on two different levels. Nine out of 10 calves with low Selenium levels showed after parturition retarded development and/or suffered from various diseases whereas the other calves (n = 17) showed no signs of clinical disease nor alterations in the race-specific development throughout the testing period.  相似文献   

15.
为研究大黄鱼对葡萄糖的耐受能力和相关糖代谢关键酶的表达量,选取体质量约为100 g的大黄鱼禁食24 h,随机分为3个实验组,分别为对照组(0.9%的无菌生理盐水,CG组),低剂量葡萄糖组(300 mg/kg体质量,LG组)和高剂量葡萄糖组(1500 mg/kg体质量,HG组)。结果显示,大黄鱼在注射高剂量和低剂量葡萄糖后,血糖均在3 h达到最高水平,且HG组的峰值显著高于LG组,LG组在24 h恢复至正常水平,HG组在24 h仍然高于正常水平。HG组、LG组注射葡萄糖后,HK、GK基因相对表达量均显著上升,其峰值出现在注射后9 h。HG组PFK基因相对表达量在注射后6 h达到峰值。HG组PEPCK基因相对表达量在注射葡萄糖后显著下降,其中最低时间点为2 h。HG组G6PD基因相对表达量在注射后6 h显著高于其他各个时间点。研究表明,注射高、低浓度葡萄糖后,均会提高大黄鱼血糖水平,且能维持较长时间。注射葡萄糖后糖酵解途径关键酶如HK、GK、PFK及糖异生途径关键酶PEPCK基因相对表达量受血糖调节,但G6Pase、FBPase表达量并不因血糖升高而下降。导致注射葡萄糖后,大黄鱼不断产生内源性葡萄糖,这是大黄鱼表现为对高血糖不耐受的原因之一。  相似文献   

16.
在水温23℃、pH值6．5、溶氧10mg／L、氨氮含量小于0．1mg／L和亚硝酸盐含量小于0．001mg／L的条件下,将恩诺沙星按照0、20、40、60、80和100mg／kg浓度,连续口服给平均体重50．0±5．0g的小体鲟（Acipenser ruthenus Linnaeus）及史氏鲟（Acipenser schrenckii Brandt）5d,停药2d后测定其血浆及肝脏组织中过氧化物岐化酶SOD的活力,以期掌握不同恩诺沙星给药浓度下,两种鲟两种组织中SOD活力变化趋势,探讨分析该酶在药物代谢过程中的作用机制。结果表明：两种鲟两种组织内均含有一定量的SOD酶,且在对照组及所有给药组肝脏中酶活力均高于血浆中。不同给药浓度下,两种鲟两种组织中SOD活力均先受诱导升高,而后被抑制降低的变化趋势,且在40mg／kg浓度组达到最大值。血浆中SOD活力受给药浓度影响较小,起伏较平稳,而小体鲟SOD活力始终高于史氏鲟。肝脏中SOD活力变化较剧烈,在低浓度组（〈40mg／kg）史氏鲟肝脏中SOD活力明显高于小体鲟,而在高给药浓度组（〉40mg／kg）则小体鲟略高于史氏鲟。  相似文献   

17.
以间隔200mg／kg的恩诺沙星设置8个浓度梯度腹腔注射红笛鲷进行急性毒性实验,测得其安全浓度为67．56mg／kg,参考安全浓度及日常生产给药量取0、20、40、80mg／kg鱼体重恩诺沙星,以腹腔注射及拌料投喂两种不同给药方式,研究恩诺沙星在该浓度范围内对红笛鲷血清中一些免疫指标及其感染细菌后死亡率的影响。实验结果表明恩诺沙星在40m非g浓度组中提高AKP活力、IgM含量、溶菌酶含量的同时可提高红笛鲷抵抗外界细菌感染的能力（P〈0．05）。当用药浓度不足（20mg/kg组）或浓度过高（80mg／kg组）,虽然对AKP活力和IgM含量也有影响,但在投喂组中,红笛鲷体内的IgM含量受抑制显著,经腹腔注射2．3×10^7 CFU／mL溶藻弧菌 （ Vibrio alginolyticus ）攻毒后,注射组中相对生理盐水组的死亡率55％;20、40、80mg／kg浓度组红笛鲷的死亡率分别为45％、30％、50％;投喂组中,0、20、40、80mg,kg浓度组红笛鲷的死亡率分别为55％、40％、30％、60％;40mg／kg浓度组中抗菌能力增强;20、80mg／kg浓度组中红笛鲷抗菌能力不受影响或有负面影响。  相似文献   

18.
Asian seabass (Lates calcarifer) is an economically important fish in Asian and Australian markets, but few pharmacokinetic (PK) data of antimicrobial drugs in this species is available. The present study investigated the PK behaviour of florfenicol (FF) through medicated feed in Asian seabass cultured at 25°C. The serum and muscle/skin concentrations of FF and its metabolite florfenicol amine (FFA) were determined by the HPLC-FLD method and analysed by one-compartmental model. The optimal dosages were determined by pharmacokinetic-pharmacodynamic (PK-PD) approach and the linear regression analysis was used to determine the withdrawal time (WDT). The PK study following a single oral administration of 15 mg/kg FF via medicated feed revealed that the absorption half-life (t1/2Ka), elimination half-life (t1/2K), peak concentration (Cmax), area under the concentration-time curve (AUC), volume of distribution (Vd/F) and clearance (CL/F) were 1.47 h, 8.07 h, 8.61 μg/ml, 146.41 h·μg/ml, 1.19 L/kg and 0.102 L/kg/h, respectively. The muscle/skin concentration-time profile was similar to that of the serum, suggesting well distribution but only a small fraction of FF was metabolized to FFA. The optimal dosage for a minimum inhibitory concentration of 2 μg/ml was calculated as 13.38 mg/kg/day. The appropriate WDT after multiple oral medications with 15 mg/kg FF once daily for 7 days was determined as 8 days. Information obtained from the current study can potentially be applied for the treatment of bacterial diseases in farming Asian seabass.  相似文献   

19.
以50、100和150 mg/kg 磺胺二甲嘧啶连续投喂中国明对虾(Fenneropenaeus chinensis)5 d,于给药期间第1、2、3、4、5天及停止投喂药物的第1、2、3、4、5、7、10天取样,测定中国明对虾免疫相关指标超氧化物歧化酶(SOD)、碱性磷酸酶(AKP)、溶菌酶(LZM)和酚氧化酶(PO)活性的变化情况。结果显示,磺胺二甲嘧啶不同给药剂量对酶活性的作用效果不同,投喂渔药期间(0–5 d),低浓度组 SOD 和 PO 活性均极显著高于对照组(P<0.01);AKP 活性于投药第2、3天极显著低于对照组(P<0.01),随后逐渐升高,于第5天显著高于对照组(P<0.05);LZM 活性于投药第3、4天显著低于对照组(P<0.05),于第5天极显著低于对照组(P<0.01)。中浓度组 SOD 活性在前2 d 显著高于对照组(P<0.05),投药3、4 d 显著低于对照组(P<0.05);AKP 活性于第5天活性最高,为对照组的1.14倍;LZM 活性在3、4、5 d 显著低于对照组(P<0.05);PO 活性在投喂药物前期1–3 d 呈上升趋势,极显著高于对照组(P<0.01),于第3天达到最高值。高浓度组 SOD 和 LZM 活性在投药期间显著低于对照组(P<0.05);AKP 活性于投药期间显著高于对照组(P<0.05);PO 活性于1、2 d 极显著高于对照组(P<0.01),随后逐渐下降。停止投喂药物阶段(6–15 d),3个浓度组各免疫相关指标均恢复至对照组水平。研究表明,低浓度磺胺二甲嘧啶对中国明对虾的免疫机能具有一定的影响,高浓度磺胺二甲嘧啶对中国明对虾的免疫机能具有明显的抑制作用。在使用抗菌药物进行抑菌或杀菌的同时,要综合考虑所选择给药剂量对对虾生理机能的影响。  相似文献   

20.
Platelet aggregation in healthy and sick cats after adding various aggregating agents is described. Feline platelets aggregate irreversibly in response to 0.15-1.0 micrograms/ml collagen, 1 microM ADP, 0.3 IU/ml test-thrombin and 0.71 NIH/ml Topostasin. Epinephrine, ristocetin and kaolin failed to cause aggregation. The aggregation function was decreased in a cat with liver damage and icterus; in 2 cats with uremia platelet aggregation was normal. Acetylsalicylic acid (ASA) (10 mg/kg iv) inhibits platelet aggregation in the presence of collagen in low concentrations; high concentrations of collagen succeeded in inducing platelet aggregation.  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