高效液相色谱法检测羊鸡组织中氟苯达唑、噻苯达唑及其代谢物残留量的研究

建立了一种可同时检测羊组织（肌肉、肝脏、肾脏、脂肪）、鸡组织（肌肉、肝脏）中氟苯达唑及代谢物2-氨基氟苯达唑、噻苯达唑及代谢物5-羟基噻苯达唑药物残留的高效液相色谱检测方法。结果表明：氟苯达唑及代谢物2-氨基氟苯达唑、噻苯达唑及代谢物5-羟基噻苯达唑在0.02～1.5μg/mL浓度范围内呈良好的线性关系r,均大于0.999。方法的定量限为20μg/kg。在鸡组织（肌肉、肝脏）中,两种药物及其代谢物在20～800μg/kg的添加浓度范围内,其回收率范围在60%～100%之间;在羊组织（肌肉、肝脏、肾脏、脂肪）中,两种药物及其代谢物在20～200μg/kg的添加浓度范围内,其回收率范围在60%～100%之间;批内变异系数均小于15%、批间变异系数均小于20%。     

脱氢醋酸钠在猪组织中的残留研究

旨在研究脱氢醋酸钠作为饲料防霉剂应用后在猪组织中的残留消除。选用33只健康杜长大三元杂交猪,200 mg/kg脱氢醋酸钠拌料饲喂1个月。分别于停药1～21 d的不同时间取肌肉、肝脏、肾脏和脂肪组织, HPLC法测定脱氢醋酸钠含量。结果表明,脱氢醋酸钠在猪肾脏和肝脏组织中的残留水平较高,肌肉次之,脂肪中最少。休药1 d时,猪肾脏、肝脏、肌肉和脂肪中的平均残留量分别为1.12 mg/kg、1.06 mg/kg、0.59 mg/kg和0.21 mg/kg;脱氢乙酸钠在组织中的含量低于定量限0.2 mg/kg水平所需要的休药时间分别为:肌肉6 d、肝脏11 d、肾脏13 d、脂肪1 d后。脱氢乙酸钠在猪不同组织中的残留消除半衰期分别为:肌肉6.7 d、肝脏7.2 d、肾脏9.1 d、脂肪5.4 d。上述结果显示,脱氢乙酸钠在猪组织中的残留消除相对较快,组织残留量均低于1.2 mg/kg。     

氯苯胍在鸡组织中的残留消除规律研究

采用超高效液相色谱一串联质谱法（UPLC-MS／MS）研究了氯苯胍在鸡组织中的残留消除规律。白来杭鸡以含氯苯胍500mg／kg饲料饲喂7d,停药后的第0、1、3、5、7天取其肌肉、肝脏、肾脏、皮和脂肪五种组织,采用UPLC-MS／MS法测定其残留状况。结果表明,氯苯胍在肌肉中残留量较小,代谢消除比较快,2d后未检出;而在脂肪、皮和肝脏中残留量较大,代谢消除较慢。     

环丙沙星在肉仔鸡组织中残留的研究

用高效液相色谱法(HPLC)检测肉仔鸡肌肉、脂肪、皮肤、肾脏和肝脏组织中环丙沙星的残留。肉仔鸡肌肉、脂肪、皮肤、肾脏和肝脏组织经二氯甲烷溶液提取,提取液浓缩后用含内标物的水溶液溶解。以0 015mol/L四丁基溴化铵/乙腈(92/8,v/v)作流动相,用SymmetryC18柱(5μm,3 9mm×150mm),在激发波长280nm、发射波长455nm处,用荧光检测器检测。将环丙沙星以0 01、0 05和0 50mg/kg分别添加到空白组织中,测得肌肉、脂肪、皮肤、肾脏和肝脏组织的回收率分别为72 2%～77 9%、73 2%～79 6%、72 4%～77 1%、69 6%～76 5%和70 0%～77 8%,变异系数均低于11 1%。用该方法测定肌肉、脂肪、皮肤、肝脏和肾脏组织中环丙沙星的最低检测限均为0 003mg/kg。肉仔鸡分别用50mg/L和100mg/L盐酸环丙沙星水溶液连续混饮各7d(35～41日龄)后,各组织中环丙沙星残留消除缓慢。休药7d时,肌肉、脂肪组织中环丙沙星残留量均低于0 03mg/kg;休药9d时,皮肤组织中环丙沙星残留量均低于0 03mg/kg;休药12d时,肾脏、肝脏组织中环丙沙星残留量均低于0 03mg/kg,而肌肉、脂肪和皮肤组织中环丙沙星残留量均低于最低检测限(0 003mg/kg);且随着环丙沙星混饮浓度的增大,环丙沙星在各组织中的残留量也相应增大。     

恩诺沙星及其代谢物在方正银鲫组织中的代谢及消除规律

近年来水产养殖中的常用药物恩诺沙星在鲫中的残留问题比较突出,但目前国家未对其在鲫中的休药期作出明确规定。为做到鲫养殖中科学合理使用恩诺沙星,在12~15℃水温条件下,以60mg/kg.b.w.剂量,对体质量为(250±10)g的健康方正银鲫(Carassius auratus gibelio)灌服恩诺沙星;在灌服后0~120d内不间断采样,用高效液相色谱-串联质谱仪检测,研究恩诺沙星及其代谢产物环丙沙星在方正银鲫鳃、血浆、肌肉、皮肤、肝脏和肾脏中的代谢及消除规律,从而为恩诺沙星在方正银鲫中的休药期制定提供参考。结果显示:灌药后,恩诺沙星在方正银鲫血浆、肌肉、肝脏、鳃、肾脏和皮肤中的达峰时间tmax分别为9、18、24、24、48和48h,肾脏、肝脏、肌肉、血浆、鳃和皮肤中的达峰浓度cmax分别为30.490、21.372、18.715、16.636、15.157和11.663mg/kg;皮肤中的消除半衰期t1/2β最大,为338.2h,血浆中最小,为93.303h;代谢产物环丙沙星的代谢及消除趋势与恩诺沙星大致相同,血浆中达峰值产生最早,tmax为18h,肾脏中的峰浓度最大,cmax为547.26μg/kg。结果表明,方正银鲫以单次口灌60mg/kg.b.w.剂量恩诺沙星,皮肤和肌肉中的恩诺沙星和环丙沙星总量需要1200度日才能满足限量要求。本研究为恩诺沙星在鲫鱼养殖中的科学使用提供了数据支撑。     

二甲硝咪唑及其代谢物在猪体内的消除规律

建立了应用HPLC法测定二甲硝咪唑（DMZ）在猪组织中残留的方法。在猪肌肉、肝脏、肾脏、脂肪等组织中添加高、中、低不同量的二甲硝咪唑，HPLC测定的回收率均在80％以上，变异系数在10％以内。肌肉、肝脏、肾脏的最低检测限为10μg/kg，脂肪为50μg/kg。同时研究了二甲硝咪唑在猪组织中残留的消除规律。试验结果认为，二甲硝咪唑在猪体内很快地转变为2－羟甲基硝基咪唑（DMZOH），DMZOH是其主要代谢物。以300、600mg/kg的剂量连续内服5d，停药48h后各组织中均检测不到DMZ及DMZOH。     

HPLC法检测环丙沙星在肉鸡组织中残留的研究

本文建立了检测环丙沙星在肉鸡组织中残留的高效液相色谱分析法。并利用建立的方法对环丙沙星在肉鸡体内的残留和消除规律进行了研究。每1L水中添加200mg环丙沙星，对120只肉鸡连续给药5d，使用高效液相色谱法对肌肉、肝脏和肾脏进行药物残留分析。残留结果研究表明，至体药13d时，在肝脏和肾脏中仍可检出0．015mg／kg和0．008mg／kg环丙沙星。在本试验条件下，建议环丙沙星，临床体药期为15d左右。     

恩诺沙星混悬液的研制及其在鸡组织中的残留研究

以恩诺沙星为主药,采用正交试验筛选配方,研制恩诺沙星混悬液,并对该制剂的药剂学特征及其在鸡组织中的残留进行研究。药剂学研究表明,混悬液的性状、pH及药物含量均符合混悬剂质量要求,且稳定性良好、易于再分散。健康鸡在饮水中添加75 mg/L(以恩诺沙星计)混悬液,自由饮水,连续用药5 d后休药;休药第5天,肌肉、肝脏及"皮肤+脂肪"组织中药物总残留量(恩诺沙星+环丙沙星)分别为11.12±10.53、79.29±28.86、50.08μg/kg±22.09μg/kg,而肾脏组织未检出;休药第8天,肌肉、肾脏、肝脏组织中均未检出恩诺沙星及环丙沙星,"皮肤+脂肪"的总残留量为13.84μg/kg±10.82μg/kg。采用WT1.4软件处理数据,计算出该混悬液在鸡体内的休药期为6 d。     

盐酸多西环素注射液在猪体内残留消除规律研究

为研究自制盐酸多西环素注射液在猪体内的残留消除规律,以10 mg/kg剂量给健康猪肌内注射盐酸多西环素注射液,每日1次给药,连续三次。在最后一次给药后7、14、21、28和35 d时间点采集肌肉、肝脏、肾脏、脂肪和注射部位肌肉,用UPLC-MS/MS法测定组织中多西环素残留量。结果表明,给药35 d后,肌肉、肝脏、肾脏、脂肪和注射部位肌肉中的多西环素残留量分别为18、24、69、10、59μg/kg,均低于最高残留限量。用WT1.4软件计算休药期,盐酸多西环素注射液在猪肌肉、肝脏、肾脏、脂肪和注射部位肌肉中的休药期分别为33.9、23.8、24.8、0和36.9 d,为保证兽药安全使用、消费者身体健康与食品安全,建议盐酸多西环素注射液在猪的休药期为42 d。     

高效液相色谱法测定动物组织中氟苯达唑、噻苯达唑及代谢物残留量的研究

建立了一种可同时检测猪、牛组织(肌肉、肝脏、肾脏、脂肪、牛奶)中氟苯达唑及代谢物2-氨基氟苯达唑、噻苯达唑及代谢物5-羟基噻苯达唑药物残留的高效液相色谱-紫外检测法。猪、牛组织样品经乙腈提取,加入Na_2SO_4盐析去杂质,异辛烷去脂肪,MCX柱净化。以0.02 mol/L乙酸铵溶液和乙腈溶液为流动相,梯度洗脱,检测波长306 nm。结果表明,氟苯达唑及代谢物2-氨基氟苯达唑、噻苯达唑及代谢物5-羟基噻苯达唑在0.01~2.0μg/mL浓度范围内呈良好的线性关系,r均大于0.99。猪、牛组织中方法的最低定量限分别为5、20μg/kg。猪、牛组织中氟苯达唑及代谢物2-氨基氟苯达唑、噻苯达唑及代谢物5-羟基噻苯达唑分别在5~200、20~200μg/kg的浓度添加水平上,其回收率范围在60%~100%之间,批内相对标准偏差小于15%、批间相对标准偏差小于20%。     

The distribution of oxytetracycline in the tissues of Swine following a single oral dose

A single oral dose of oxytetracycline hydrochloride (50 mg/kg) produced detectable residues in the following tissues; adrenal, bile, fat, heart, kidney (cortex), kidney (medulla), liver, lung, lymph node (mesenteric), muscle, serum, spleen, thyroid and urine. The highest residue levels were observed in the urine (441 μg/mL) at three hours after administration and they were still present at 48 hours. Maximum serum levels were observed at two hours after administration. Bile samples were positive for inhibitors in all animals sampled. Drug residues were not detected in spleen, thyroid, lymph node, adrenals and heart at 48 hours.

Drug levels in important edible tissues were expressed as a percentage of drug levels in two tissues with high drug concentrations — urine and kidney cortex. The percentages were highly variable when compared with urine and much less variable when compared to kidney cortex.

Kidney cortex appears to be an excellent tissue for drug residue monitoring.

     

乙酰甲喹及其主要代谢物在鸡体内的残留消除规律研究

建立了高效液相色谱串联质谱（HPLC—MS／MS）法用于乙酰甲喹及其6种主要代谢物的检测。将65只健康白羽鸡分为两组,10只为空白对照组,其余为试验组。试验组施以20mg／kgb．w．灌胃乙酰甲喹悬浊液,1d2次,连续3d。在给药结束后2、4、6、12、16、24、30、36、48、72、120h分别宰杀5只鸡,采集血液和可食性组织（肌肉、肝脏、肾脏和皮脂）样品。结果表明：乙酰甲喹原药在组织和血浆中迅速消除;乙酰甲喹的代谢物广泛存在于鸡的可食性组织和血浆中;代谢物的残留消除过程较为复杂,代谢物在肌肉和肝脏中残留量较多,在皮脂中残留时间最长。研究结果将有助干榍示7．酷甲喹存鸡体内的砖留消除期,律．     

磺胺—6—甲氧嘧啶在肉鸡的组织动力学与残留量研究

本文详细研究了肉鸡单剂量口服磺胺-6-甲氧嘧啶混悬液后药物的组织动力学特征,并对血药和组织药物浓度进行了回归分析。 组织动力学研究发现:药物按一级速率过程从组织消除,肌、肝、心、肾中达峰时间分别为6.84、4.63、5.32和5.78小时,组织半衰期分别为4.74、9.01、8.02、和9.18小时,给药后约经110.5小时,肾中药残可降至0.1ppm以下,而肌肉仅需70小时。 回归分析表明:当血药降至MIC(50ppm)时,肌、肝、心、肾中药物含量分别为19.95、14.65,24.98和68.56ppm,回归方程的建立为药物组织残留的间接估测提供了简捷的方法。     

Residues of spinosad in the tissues of sheep after aerosol treatment of blowfly myiasis

OBJECTIVE: To measure the residues of spinosad and chlorhexidine in the tissues of sheep after treatment of blowfly strike. PROCEDURE: Fourteen sheep with natural myiasis and 12 with artificial infestations of Lucilia cuprina larvae had the wool removed over their infestations and were treated with an aerosol wound dressing containing spinosad and chlorhexidine. Sheep were killed up to 14 days after treatment and residues of the chemicals measured in tissues. RESULTS: Chlorhexidine was not detected in any tissue. Residues of spinosad were highest in fat, lowest in muscle and intermediate in liver and kidney. The highest residue detected was 0.2 mg/kg spinosad in perirenal fat 7 days after generous treatment of a sheep with a large fly strike. Residues of spinosad in fat peaked 3 to 7 days after treatment and 1 to 3 days after treatment in liver and kidney. CONCLUSION: These studies present a realistic worst-case in struck sheep and at the highest dose studied, equivalent to 5.8 mg spinosad per kg body weight, the maximum residue detected of 0.2 mg/kg in peri-renal fat was 20% of the Australian maximum residue limit. Muscle, liver and kidney residues of spinosad were also below the Australian maximum residue limits at all times.     

盐酸多西环素片在羔羊体内残留消除规律及休药期分析

旨在确定盐酸多西环素片按照给药说明给药后在羔羊体内的残留消除规律及休药期。将盐酸多西环素片根据体重以5 mg·kg^-1内服给药,间隔24 h,连续给药5次。在最后1次给药后,分别在第0（12小时）、1、2、3、5、7和9天时间点采集羔羊脂肪、肌肉、肝和肾,采用建立并验证的HPLC-VWD方法测定组织中多西环素的含量。结果显示：方法学考察结果表明,在50~5 000 ng·mL^-1添加的线性方程和相关系数为y=0.044x-0.414,R²=0.999。试验结果表明,多西环素在羔羊组织中代谢快速,最后1次给药后第9天,在肌肉、肝、肾和脂肪中均未检测到多西环素。本试验以5 mg·kg^-1体重内服给予羔羊盐酸多西环素片后,根据欧洲药品评估机构法规《EMEA/CVMP/036/95》,建议盐酸多西环素片在羔羊组织中的休药期为2 d。     

Pharmacokinetic and tissue residue characteristics of fenprostalene, a prostaglandin F2 alpha analog, in swine

Fenprostalene, a prostaglandin F2 alpha analog, can be used to induce parturition in swine. As part of the approval process for that indication, pharmacokinetic characteristics of the absorption and elimination of fenprostalene and the depletion of drug residues from the principal edible tissues of swine were studied. Blood samples, urine, and feces were collected from 8 gilts (body weight, 95 +/- 1.7 kg) for up to 72 hours after a single dose of 0.5 mg of 13,14-[3H]-fenprostalene in polyethylene glycol-400 was administered SC. At intervals of 24, 48, 72, and 168 hours after dosing, 2 gilts each were killed, and samples of liver, kidney, muscle, and abdominal fat were obtained for analysis. The mean (+/- SEM) maximal concentration of fenprostalene radioequivalents in plasma (0.41 +/- 0.05 nanogram-equivalents/ml; n = 8) was observed at 12 hours and decreased biexponentially, with half-lives of approximately 8 hours and 9 days. Mean cumulative recovery (n = 4) of the administered dose by 72 hours was 61.2 +/- 5.9% in urine and 18.5 +/- 2.6% in feces. The highest tissue fenprostalene concentration was in kidneys and liver, probably reflecting the role of those organs in excreting fenprostalene. Rates of depletion of fenprostalene equivalents from the injection site, kidneys, and liver were comparable with those previously observed in cattle. The composition of residue in the liver of 2 gilts slaughtered 12 hours after SC administration of [3H]-fenprostalene was examined in a second study. Results suggested that approximately 4% of the total residue was pharmacologically potent fenprostalene or the carboxylic acid form of fenprostalene.(ABSTRACT TRUNCATED AT 250 WORDS)     

Enramycin在鸡体内残留分析研究

本文报道了Ｅｎｒａｍｙｃｉｎ在鸡体内的残留分析结果。供分析的组织经胃蛋白酶消化，甲醇及盐酸混合液抽提，ＸＡＤ－２柱分离杂质、薄层层析及枯草杆菌ＡＴＣＣ６６３３生物显像，进行定性及定量分析。此法在肝、肾、肌肉、脂肪组织和血中Ｅｎｒａｍｙｃｉｎ的回收率分别为５７．７０％、４６．６５％、４４．８０％、３９．３５％及４６．６０％，其敏感度为２５ｐｐｂ。测试样来自喂饲１０ｐｐｍ Ｅｎｒａｍｙｃｉｎ８周的试验     

Pharmacokinetics of amoxycillin and the rate of depletion of its residues in pigs

Six pigs were used in a two-period crossover study to investigate the pharmacokinetics of amoxycillin after single intravenous and oral doses of 20 mg/kg bodyweight. Twelve pigs were used to study the residues of the drug in muscle, kidney, liver and fat after they had received daily oral doses of 20 mg/kg amoxycillin for five days. The mean (sd) elimination half life (t1/2beta) and mean residence time of amoxycillin in plasma were 3.38 (0.30) and 3.54 (0.43) hours, respectively, after intravenous administration and 4.13 (0.50) and 4.47 (0.30) hours, respectively, after oral administration. After oral administration, the maximum plasma concentration (Cmax) was 7.37 (0.42) microg/ml and it was reached after 0.97 (0.29) hours. Six days after the last oral dose, the mean concentration of amoxycillin in the pigs' kidneys was 21.38 ng/g and in the liver it was 12.32 ng/g, but no amoxycillin could be detected in fat or muscle; the concentrations of amoxycillin in edible tissues were less than the European Union maximal residue limit of 50 microg/kg.     

Tylosin depletion from edible pig tissues

The depletion of tylosin from edible pig tissues was studied following 5 days of intramuscular (i.m.) administration of 10 mg/kg of tylosin to 16 crossbreed pigs. Animals were slaughtered at intervals after treatment and samples of muscle, kidney, liver, skin+fat, and injection site were collected and analysed by high-performance liquid chromatography (HPLC). Seven days after the completion of treatment, the concentration of tylosin in kidney, skin+fat, and at the injection site was higher than the European Union maximal residue limit (MRL) of 100 microg/kg. Tylosin residues in all tissues were below the quantification limit (50 microg/kg) at 10 and 14 days post-treatment.     

Female sex steroid residues in the tissues of steers treated with progesterone and oestradiol-17 beta.

Progesterone, oestrone and oestradiol-17 beta levels in the muscle, fat, liver, kidney and plasma of steers treated with Synovex S, untreated steers, and cows during the normal oestrous cycle, were examined. Progesterone levels in female tissues reached a maximum in the luteal phase and fell to a minimum in the follicular phase. Oestrogen levels (oestrone and oestradiol-17 beta) did not change during the cycle. Progesterone and oestrogen levels in the tissues of steers treated with Synovex S and untreated steers were not statistically different. Tissue progesterone levels in steers were much lower than those in cows during the luteal phase. The highest oestrogen levels were found in the fat of female animals. These results indicate that residue levels of progesterone and oestrogen in the muscle and fat of steers treated with Synovex S were within the physiological range, and lower than those of cows.