儿茶素在家兔体内的药物动力学及生物利用度研究

对家兔单剂量静注和灌服儿茶素 (Catechin) 2 5mg/kg体重各 5只。用高效液相色谱法测定其血药浓度。房室模型分析表明静注给药后的药时数据符合无吸收二室开放模型 ,主要动力学参数为 :t1 / 2α=( 0 .1 5± 0 .0 1 )h ,t1 / 2 β=( 0 .5 8± 0 .0 2 )h ,Vc=( 1 .41± 0 .0 8)L ,Vβ=( 2 .97±0 .1 1 )L ,ClB=( 3.5 3± 0 .1 0 )L/h ,AUC =( 1 6.95± 1 .5 2 )mg/(L·h)。灌服儿茶素的药时数据符合一级吸收一室开放模型 ,主要药物动力学参数为 :t1 / 2Ka=( 0 .39± 0 .0 6)h ,t1 / 2Ke=( 0 .79±0 .1 1 )h ,tmax=( 0 .78± 0 .1 1 )h ,Cmax=( 3.35± 0 .1 6)mg/L ,AUC =( 7.45± 0 .94)mg/(L·h) ,F =( 4 4.1 8± 3.5 9) %。儿茶素在健康家兔体内的药动学特征是 :吸收迅速 ,达峰时间短 ,消除快 ,半衰期短 ,表观分布容积较大 ,口服摄入吸收不完全     

儿茶素在家兔体内的生物利用度及药物动力学研究

选健康家兔 ,单剂量静注和灌服儿茶素 (Catechin) 2 5 mg/ kg,用高效液相色谱法测定其血药浓度 ,3P87计算机程序处理所得血药浓度—时间数据。结果健康家兔静注给药的药时数据符合无吸收二室开放模型 ,主要动力学参数为 :t1 /2α(0 .15± 0 .0 1) h,t1 /2β(0 .5 8± 0 .0 2 ) h,Vc (1.4 1± 0 .0 8) l,Vβ(2 .97± 0 .11) l,Cl B(3.5 3±0 .10 ) l/ h,AU C(16 .95± 1.5 2 ) mg/ (l· h) ,K1 0 (2 .5 2± 0 .2 0 ) h- 1 ,K2 1 (2 .2 5± 0 .15 ) h- 1 ,K1 2 (1.17± 0 .15 )h- 1 。健康家兔灌服儿茶素的药时数据符合一级吸收一室开放模型 ,主要药物动力学参数为 :t1 /2 ka(0 .39± 0 .0 6 )h,t1 /2 ke(0 .79± 0 .11) h,tmax(0 .78± 0 .11) h,Cmax(3.35± 0 .16 ) mg/ l,AU C (7.4 5± 0 .94 ) m g/ (l· h) ,F (6 4±7.0 0 ) %。儿茶素在健康家兔体内的药动学特征是 :吸收迅速 ,达峰时间短 ,消除快 ,半衰期短 ,表观分布容积较大 ,口服摄入吸收不完全     

替米考星静脉及皮下注射后在绵羊体内的药代动力学研究

健康成年杂交绵羊静脉和皮下注射替米考星注射液后,用反相高效液相色谱法测定不同时间点血清中的药物浓度。采用3p97药代动力学程序软件处理数据,替米考星两种给药途径的药 时数据均符合二室开放模型静脉注射给药(5 mg/kg bw)的主要药代动力学参数: t1/2a 为 0. 611±0. 017 h、t1/2β为 23. 215±0. 459 h、AUC为11 815±0.396(μg/mL)·h、CL(s)为 0.424±0.014 L/(kg·h)。替米考星皮下注射主要药代动力学参数: 1mg/kg bw剂量组 t1/2a 为 1 751±0 557 h、t1/2β为 22 896±2 747 h、t1/2Ka 为 0. 100±0. 025 h、AUC 为 25. 828±1 479 (μg/mL)·h、CL(s)为0.393±0.017 L/(kg·h),Tmax为0.500±0.065 h,Cmax为1.424±0.156μg/mL、F为109.28%±6.25%。30 mg/kg bw剂量组 t1/2a为1.342±0.244 h、t1/2β为 20.052±1.236 h、t1/2Ka为 0.086±0.015h、AUC为57 575±6.760 (μg/mL)·h、CL(s)为0.527±0.068 L/(kg·h)、Tmax为0.437±0.039 h、Cmax为 3.343±0 512μg/mL、F为81.22%±9.54%。结果表明,绵羊静脉和皮下注射替米考星体内分布广,消除缓慢;皮下注射后在体内吸收迅速,达峰快,生物利用度高。     

麻保沙星(marbofloxacin)在鸡体内的生物利用度及药物动力学

选用 36只 5 1～ 6 0日龄健康岭南黄鸡 ,随机均分为 3组 ,对静注、肌注及内服麻保沙星 (2 .5 mg/ kg)的生物利用度和药物动力学进行了研究。用三氯甲烷提取血浆中的药物 ,反相高效液相色谱法测定血浆中麻保沙星的浓度 ,MCPKP计算机程序处理所得到的血药浓度 -时间数据。静注给药的药时数据适合三室开放模型 ,主要药动学参数分别为 :t1 /2π(0 .19± 0 .0 3) h;t1 /2α(2 .0 7± 0 .2 7) h;t1 /2β(6 .5 2± 0 .6 9) h;V1 (0 .48± 0 .0 3) L / kg;Vd(area) (2 .0 6± 0 .39)L/ kg;Vd(ss) (1.0 5± 0 .0 6 ) L/ kg;Cl B(0 .19± 0 .0 2 ) L/ (kg· h) ;AUC(13.95± 1.0 7) mg· kg- 1 · h。肌注给药的药时数据适合一级吸收二室开放模型 ,主要药动学参数分别为 :t1 /2 Ka(0 .5 4± 0 .0 5 ) h;t1 /2α(2 .33± 0 .2 0 ) h;t1 /2β(6 .2 7± 0 .46 )h;tmax(1.5 7± 0 .0 9) h;Cmax(1.88± 0 .0 5 ) m g/ L ;AUC(13.18± 0 .6 7) mg· kg- 1 · h;F(94.45± 4.80 ) %。内服给药的药时数据适合一级吸收二室开放模型 ,主要药动学参数分别为 :t1 /2 Ka(0 .42± 0 .0 6 ) h;t1 /2α(2 .31± 0 .2 5 ) h;t1 /2β(6 .48±0 .6 6 ) h;tmax(1.35± 0 .12 ) h;Cmax(1.83± 0 .18) mg/ L;AUC(13.5 5± 0 .6 7) mg· k     

阿莫西林钠在猪体内的生物利用度及药动学研究

1 4头健康杂种猪 ,随机平均分为两组 ,按随机交叉试验设计 ,进行静注及内服阿莫西林钠 (1 0mg/kg)的药动学研究 ,以及肌注阿莫西林钠及阿莫西林钠长效制剂 (1 0mg/kg)的药动学比较。高效液相色谱法测定猪血浆中阿莫西林的浓度 ,MCPKP计算机程序处理血浆药物浓度 时间数据。健康猪静注给药的药时数据适合二室开放模型 ,主要药物动力学参数为 :t1 /2α0 31± 0 1 6h;t1 /2 β2 2 9± 0 94h ;V1 0 2 2± 0 1 2L/kg ;Vd(area) 1 0 6± 0 45L/kg ;ClB0 33±0 0 7L·kg- 1 ·h- 1 ;AUC31 67± 7 0 9mg·L- 1 ·h。健康猪内服给药的药时数据适合一级吸收二室模型 ,主要药物动力学参数为 :t1 /2ka0 74± 0 36h ;t1 /2 β5 96± 3 41h ;tmax1 52± 0 43h ;Cmax5 33± 2 0 7μg/mL ;AUC2 3 89± 9 40mg·L- 1 ·h ;F79 64 %± 38 47%。健康猪肌注阿莫西林钠和阿莫西林钠长效制剂的药时数据均适合一级吸收二室模型 ,主要药物动力学参数为 :t1 /2ka0 1 1± 0 0 5h和 0 0 9± 0 0 5h ;t1 /2 β3 2 8± 1 89h和 7 32± 3 55h ;tmax0 33± 0 1 4h和 0 36±0 1 6h ;Cmax1 6 51± 4 41 μg/mL和 1 8 98± 2 70 μg/mL ;AUC30 61± 8 2 7mg·L- 1 ·h和 49 44± 1 1 31mg·L- 1 ·h ;F96 65     

克蚕菌与家蚕血浆蛋白结合率的研究

用平衡透析法测定克蚕菌与家蚕血浆蛋白结合率 ,克蚕菌浓度用标准曲线法求出。克蚕菌血浆浓度在5 74～ 188.6 7μg/mL时血浆蛋白结合率为 5 3 4 0 %～ 2 9.2 8%。结合参数的最大结合力 ( β)为 5 88× 10 -6mol/g;解离常数 (Kdp)为 1 0 8× 10 -4mol/L ;结合常数 (K)为 9 82× 10 3 L/mol;结合部位 (N)为 0 9132。克蚕菌与家蚕血浆蛋白具有单一类型的结合部位 ,药物血浆浓度升高结合率下降。     

国产表阿佛菌素在绵羊体内的药代动力学研究

用反相高效液相色谱结合荧光检测法,对试验绵羊经静脉、皮下单剂量注射0 2 mg/kg表阿佛菌素的药代动力学进行了研究。血样提取物通过C18小柱富集、洗脱,甲醇洗提部分经加入1 甲基咪唑和三氟乙酸酐的乙腈液衍生化后进行色谱分析。血药浓度在 2. 5 ~ 200 ng/mL 范围呈良好线性关系(R= 0 996 8),方法平均回收率96 65%±3.84%,血药最低检测限 2.5 ng/mL,日内、日间变异系数分别小于 10%、12%。2 种途径给药后体内药物运转分别符合二室和一室开放模型。主要药代参数如下,静脉注射:消除半衰期(T1/2β)12.66±2.05 h,药时曲线下面积(AUC0~74)1.02±0 30 (mg/L)·h,fc=0 13±0 05; 皮下注射:吸收半衰期(T1/2ka )4.42±1.04 h,峰浓度(Cmax)0 02±0 01 μg/mL,峰时(Tmax ) 15. 36±2. 91 h,消除半衰期(t1/2k ) 26. 22±9. 04 h,药时曲线下面积(AUC0~122)1.19±0 37 (mg/L)·h。上述结果表明,绵羊静脉注射表阿佛菌素后体内药物分布广泛,消除较慢。皮下注射吸收好,消除比静脉注射更为缓慢,体内药物平均滞留时间长。     

欧孢美诺在猪体内的药物代谢动力学研究

本试验以6头长白猪(W18.3～18.8kg)为靶对象,进行了兽用长效粉针剂欧孢美诺单剂量用药的药代动力学研究;以2万IU/kg进行单剂量用药后,其药代动力学特征符合有滞留的一级吸收二室模型(C=2.289e-0.259t+8.241e-0.016t+10.53e-0.168t)具体参数为:Tl/2α2.68±0.12(h)、T1/2β43.31±2.06(h)、T1/2ka4.12±0.37(h)、Auc585.679±51.58(μ/mL·h)、vd3878.74±201.19(100mL/kg)、CLB620.61±19.88(mL/kg/min)、Tmax2.14±0.16(h)、Cmax38.59±2.089(μ/mL)。以0.25μ/mL为安唐西林的有效血药浓度,那么欧孢美诺在在猪体内的有效血药浓度维持时间tcp(ther)是216.48h。     

“棘防E号”在绵羊体内的药代动力学研究

4只绵羊口服“棘防E号”后测定血液中血药浓度变化及药代动力学参数值。结果表明血药浓度—时间曲线符合一室分布模型。药代动力学参数结果为:吸收速度常数(ka)(2.03±0.07)h-1、消除速率常数(ke)(0.36±0.03)h-1、峰时间(Tmax)(5.65±0.77)h、吸收相半增期(T1/2/ka)(3.15±0.18)h、消除相半衰期(T1/2/ke)(4.24±0.17)h、峰浓度(Cmax)(4.98±0.68)mg.L-1、药时曲线下面积(AUC)(27.65±3.54)mg.h-1.L-1、清除率平均值(ALB)(0.53±0.07)mg.kg-1.h-1、体内表观分布容积(Vd)(1.93±0.08)L.kg-1。     

肉仔鸡静注和内服环丙沙星(ciprofloxacin)的药物动力学

16只健康 AA肉仔鸡 ,随机分成 2组 ,每组 8只 ,按 10 mg/ kg剂量分别进行静注和内服单剂量环丙沙星药动学试验。血浆中药物浓度用高效液相色谱法测定 ,血药浓度 -时间数据用 MCPKP药动学计算机程序处理。结果表明 ,静注给药后的药时数据符合无吸收二室开放模型 ,主要动力学参数分别为 :t1 /2α为 (0 .2 34± 0 .0 49) h,t1 /2β为 (10 .118±0 .2 71) h,VB为 (1.374± 0 .12 4) L/ kg,CLB为 (0 .0 94± 0 .0 0 9) L· kg- 1 · h- 1 ,AUC为 (10 7.0 6 8± 10 .6 40 ) mg· L- 1· h。内服给药后的药时数据符合一级吸收一室开放模型 ,主要动力学参数分别为 :t1 /2 kα为 (0 .114± 0 .0 0 8) h,t1 /2 k为(7.784± 0 .5 14) h,Tp 为 (0 .70 2± 0 .0 31) h,Cmax为 (5 .736± 0 .5 15 ) m g/ L,AUC为 (6 8.6 2 2± 8.147) mg· L- 1· h,F为 (6 4.0 92± 7.6 10 ) %。肉仔鸡静注环丙沙星在其体内消除较慢 ,分布广泛 ;内服给药吸收迅速 ,消除较静注给药快。     

喹烯酮及其主要代谢物在猪体内的药动学研究

本试验旨在研究喹烯酮及其主要代谢物在猪体内的药物代谢动力学过程。将喹烯酮按40 mg/kg的剂量对7头猪进行灌胃给药,采用HPLC-MS/MS法测定血浆中喹烯酮及其主要代谢物的浓度,药代动力学软件WinNonlin 5.2处理血浆中药物浓度－时间数据。灌胃给药后猪血浆中能检测到原药和N1-脱氧喹烯酮、脱二氧喹烯酮及3-甲基喹噁啉-2-羧酸(MQCA)3种代谢物。喹烯酮的浓度－时间数据符合一级吸收一室开放模型,其主要药代动力学参数为:T_1/2Ka＝(0.97±0.08)h,T_1/2λz＝(2.79±0.16)h,CL＝(26.03±0.65)L/h·kg,Cmax＝(0.26±0.01)μg/mL,Tmax＝(2.23±0.06)h,AUC＝(1.54±0.04)h·μg/mL;采用统计矩法处理N1-脱氧喹烯酮和脱二氧喹烯酮的浓度－时间数据,N1-脱氧喹烯酮主要药代动力学参数为:Tmax＝(6.33±1.37)h,Cmax＝(8.81±2.08) ng/mL,T_1/2λz＝(3.03±1.27)h,AUC＝(0.07±0.01)h·ng/mL,MRT＝(6.58±0.40)h;脱二氧喹烯酮的主要药动学参数:Tmax＝(10.29±0.29)h,Cmax＝(6.20±1.11)ng/mL,T_1/2λz＝(5.84±2.78)h,AUC＝(0.15±0.01)h·ng/mL,MRT＝(3.64±0.72)h。同时,在少数时间点检测到代谢物MQCA。猪口服喹烯酮后,吸收较快,消除较慢。血浆中检测到N1-脱氧喹烯酮、脱二氧喹烯酮及3-甲基喹噁啉-2-羧酸3种代谢物,且浓度较低、消除缓慢。     

硫酸头孢喹肟在鸭体内的药动学及生物利用度研究

试验将20只2月龄健康番鸭,随机分为2组,每组10只,雌雄各半,分别进行静脉注射和口服硫酸头孢喹肟给药的药动学研究。静脉注射和口服的给药剂量分别为10和20 mg/kg。以反相HPLC测定血浆中硫酸头孢喹肟的浓度,血药浓度—时间数据用3P97药动学程序软件处理。鸭单剂量静脉注射给药后,血药浓度—时间数据符合无吸收二室开放模型,其主要动力学参数分别为:V（c）,（1.146±0.02） L/kg;t_1/2α,（0.290±0.02）h;t_1/2β,（1.691±0.15）h;AUC （6.635±0.18）（mg·h）/L;CL（s）,（1.508±0.04）L/（kg·h）。鸭口服硫酸头孢喹肟的血药浓度—时间数据符合一级吸收一室开放模型,主要动力学参数分别为:t_1/2（ka）,（0.45±0.05）h;t_1/2（ke）,（0.96±0.29）h;T_（peak）,（0.91±0.09）h;C_（max）,（3.14±0.64）mg/L;AUC,（8.29±1.26）（mg·h）/L;F,（62.55±0.10）%。硫酸头孢喹肟在体内的药动学特征表现为吸收迅速、分布广泛、消除迅速。但口服给药在鸭体内生物利用度低,可能由于硫酸头孢喹肟的脂溶性低,其在消化道吸收率低所致。但8 h内能保持有效血药浓度范围（（0.14±0.03）~（3.14±0.64）μg/mL）,可抑制鸭疫里默氏杆菌及其他细菌感染。     

Pharmacokinetics of ceftiofur sodium and ceftiofur crystalline free acid in neonatal foals

Ceftiofur, a third generation cephalosporin, demonstrates in vitro efficacy against microorganisms isolated from septicemic neonatal foals. This pharmacokinetic study evaluated the intravenous and subcutaneous administration of ceftiofur sodium (5 mg/kg body weight; n = 6 per group) and subcutaneous administration of ceftiofur crystalline free acid (6.6 mg/kg body weight; n = 6) in healthy foals. Plasma ceftiofur- and desfuroylceftiofur-related metabolite concentrations were measured using high performance liquid chromatography following drug administration. Mean (±SD) noncompartmental pharmacokinetic parameters for i.v. and s.c. ceftiofur sodium were: AUC(0→∝) (86.4 ± 8.5 and 91 ± 22 h·μg/mL for i.v. and s.c., respectively), terminal elimination half-life (5.82 ± 1.00 and 5.55 ± 0.81 h for i.v. and s.c., respectively), C(max(obs)) (13 ± 1.9 μg/mL s.c.), T(max(obs)) (0.75 ± 0.4 h for s.c.). Mean (± SD) noncompartmental pharmacokinetic parameters for s.c. ceftiofur crystalline free acid were: AUC(0→∝) (139.53 ± 22.63 h·μg/mL), terminal elimination half-life (39.7 ± 14.7), C(max(obs)) (2.52 ± 0.35 μg/mL) and t(max(obs)) (11.33 ± 1.63 h). No adverse effects attributed to drug administration were observed in any foal. Ceftiofur- and desfuroylceftiofur-related metabolites reached sufficient plasma concentrations to effectively treat common bacterial pathogens isolated from septicemic foals.     

盐酸诺氟沙星在家蚕体内的药物动力学研究

为了给家蚕细菌病的预防和治疗提供合理用药的理论依据 ,采用微生物测定法研究了盐酸诺氟沙星在健康家蚕体内的药物动力学特征 ,以MCPKP药代动力学程序处理药时数据。结果表明 :盐酸诺氟沙星在蚕体内的药时数据符合一级吸收一室开放式模型 ,主要药物动力学参数 :T1/2Ka=1 797± 0 0 2 3h ,T1/2Kel=1 778± 0 0 12h ,Tmax=3 4 2 8± 0 0 0 8h ,Cmax=14 80 8± 0 6 4 5 μg/mL。     

牛蒡子中牛蒡苷元在仔猪体内的药物动力学研究

为研究牛蒡子粉在仔猪体内的药物动力学特征,了解其在仔猪体内的吸收、分布、转化和排泄规律,为新兽药的研发和临床用药提供理论参考依据。选取健康仔猪8头(30.0±5.0kg),以1.0g/kg.bw的牛蒡子粉灌胃给药,不同时间点前腔静脉采血,采用HPLC法对猪血浆中牛蒡苷元的浓度进行分析。牛蒡子粉灌胃给药后,符合有吸收二室模型,主要药物动力学参数为：吸收半衰期(t_1/2ka)为0.274±0.102 h,分布半衰期(t_1/2α)1.435±0.725h;消除半衰期(t_1/2β)63.467±29.115 h;表观分布容积(V_d)1.680±0.402 L/kg;清除率(CL_b)0.076±0.028L/(h.kg);达峰时间(t_max)为0.853±0.211 h,峰浓度(c_max)为0.430±0.035μg /mL,药时曲线下面积(AUC)14.672±4.813μg.h/mL。试验表明：牛蒡子粉口灌后在仔猪体内吸收迅速、分布广泛、代谢消除缓慢,能够较长时间发挥药理作用。     

Pharmacokinetic study of rhizoma Curcumae oil and rhizoma Curcumae oil-β-cyclodextrin inclusion complex in pigs after oral administration

Pharmacokinetics of rhizoma Curcumae oil-pure drug (RCO-PD) and its β-cyclodextrin inclusion complex (RCO-βCD) were studied in a randomized two-way crossover design following a single oral administration of the two formulations. Germacrone concentrations in plasma were determined by high-performance liquid chromatography with UV detector. The concentrations vs. time data were analyzed by a noncompartmental pharmacokinetic method. The result showed that germacrone in both groups was rapidly absorbed followed by a slow elimination. The main parameters in RCO-PD group were as follows: t(1/2λz) 6.63±1.08 h, C(max) 2.50±0.34 μg/mL, MRT 7.19±0.93 h, and AUC(0-∞) 13.92±2.75 mg/L·h, while in RCO-βCD group, t(1/2λz) 6.77 ± 0.67 h, C(max) 2.98±0.24 μg/mL, MRT 8.87±0.76 h, and AUC(0-∞) 21.60 ± 1.95 mg/L·h, respectively. The above results indicated that C(max), T(max), AUC(0-t), AUC(0-∞), and MRT in RCO-βCD group were significantly different from RCO-PD group, and the relative bioavailability of RCO-βCD group is significantly higher while compared to RCO-PD group (F=156%, with its 90% confidence interval of 145-169%).     

肌注硫酸庆大霉素在大肠杆菌感染鸡体内的药动学试验

为分析硫酸庆大霉素在健康和鸡大肠杆菌感染鸡体内的药物动力学特征,试验通过给健康鸡腹腔注射大肠杆菌O157,以临床症状、病理剖检和微生物检查为指标,成功建立鸡大肠杆菌感染模型。选取健康鸡和患病鸡各8只,分别以20 mg/kg体重单剂量肌内注射硫酸庆大霉素,分别于0.167、0.25、0.5、0.75、1、2、3、4、6、8和12 h时间点采血,采用管碟法测定血浆中庆大霉素的浓度。结果显示:试验所建立的标准曲线相关性好,相关系数均达0.990以上,日内、日间变异系数均小于10%。肌注给药后,硫酸庆大霉素在鸡体内吸收迅速,房室模型分析表明,健康鸡与患病鸡药时数据均符合有二室开放模型,硫酸庆大霉素在健康鸡体内峰浓度(Cmax)为(15.01±3.51)μg/mL,药时曲线下面积(AUC)为(100.79±5.14)μg/mL·h,消除半衰期(t1/2β)为(4.41±1.32)h,达峰时间(Tp)为(1.27±0.50)h。硫酸庆大霉素在患病鸡体内峰浓度(Cmax)为(12.50±2.19)μg/mL,药时曲线下面积(AUC)为(83.38±4.19)μg/mL·h,消除半衰期(t1/2β)为(4.18±1.17)h,达峰时间(Tp)为(0.97±0.05)h。结果表明:硫酸庆大霉素在患病鸡体内的峰浓度和药时曲线下面积低于健康鸡(P<0.05),因此对于已感染大肠杆菌的病鸡可以考虑适当增加给药剂量。     

Pharmacokinetics of ceftiofur crystalline free acid after single subcutaneous administration in lactating and nonlactating domestic goats (Capra aegagrus hircus)

Doré, E., Angelos, J. A., Rowe, J. D., Carlson, J. L., Wetzlich, S. E., Kieu, H. T., Tell, L. A. Pharmacokinetics of ceftiofur crystalline free acid after single subcutaneous administration in lactating and nonlactating domestic goats (Capra aegagrus hircus). J. vet. Pharmacol. Therap. 34 , 25–30. Six nonlactating and six lactating adult female goats received a single subcutaneous injection of ceftiofur crystalline free acid (CCFA) at a dosage of 6.6 mg/kg. Blood samples were collected from the jugular vein before and at multiple time points after CCFA administration. Milk samples were collected twice daily. Concentrations of ceftiofur and desfuroylceftiofur‐related metabolites were measured using high‐performance liquid chromatography. Data were analyzed using compartmental and noncompartmental approaches. The pharmacokinetics of CCFA in the domestic goat was best described by a one compartment model. Mean (±SD) pharmacokinetic parameters were as follows for the nonlactating goats: area under the concentration time curve_0–∞ (159 h·μg/mL ± 19), maximum observed serum concentration (2.3 μg/mL ± 1.1), time of maximal observed serum concentration (26.7 h ± 16.5) and terminal elimination half life (36.9 h; harmonic). For the lactating goats, the pharmacokinetic parameters were as follows: area under the concentration time curve_0–∞ (156 h·μg/mL ± 14), maximum observed serum concentration (1.5 μg/mL ± 0.4), time of maximal observed serum concentration (46 h ± 15.9) and terminal elimination half life (37.3 h; harmonic). Ceftiofur and desfuroylceftiofur‐related metabolites were only detectable in one milk sample at 36 h following treatment. There were no significant differences in the pharmacokinetic parameter between the nonlactating and lactating goats.     

Comparative pharmacokinetics of diaveridine in pigs and chickens following single intravenous and oral administration

Comparative pharmacokinetic profiles of diaveridine following single intravenous and oral dose of 10 mg/kg body weight in healthy pigs and chickens were investigated, respectively. Concentrations of diaveridine in plasma samples were determined using a validated high‐performance liquid chromatography–ultraviolet (HPLC‐UV) method. The concentration–time data were subjected to noncompartmental kinetic analysis by WinNonlin program. The corresponding pharmacokinetic parameters in pigs or chickens after single intravenous administration were as follows, respectively: t_1/2β (elimination half‐life) 0.74 ± 0.28 and 3.44 ± 1.07 h; V_d (apparent volume of distribution) 2.70 ± 0.99 and 3.86 ± 0.92 L/kg; Cl_B (body clearance) 2.59 ± 0.62 and 0.80 ± 0.14 L/h/kg; and AUC_0‐∞ (area under the blood concentration vs. time curve) 4.11 ± 1.13 and 12.87 ± 2.60 μg?h/mL. The corresponding pharmacokinetic parameters in pigs or chickens after oral administration were as follows, respectively: t_1/2β 1.78 ± 0.41 and 2.91 ± 0.57 h; C_max (maximum concentration) 0.43 ± 0.24 and 1.45 ± 0.57 μg/mL; T_max (time to reach C_max) 1.04 ± 0.67 and 3.25 ± 0.71 h; and AUC_0‐∞1.33 ± 0.55 and 9.28 ± 2.69 μg?h/mL. The oral bioavailability (F) of diaveridine in pigs or chickens was determined to be 34.6% and 72.2%, respectively. There were significant differences between the pharmacokinetics profiles in these two species.     

Pharmacokinetics of ivermectin in cats receiving a single subcutaneous dose

Ivermectin is effective against ecto- and endoparasites. It is included in a plan of the Filariasis Division, Thailand for filariasis control and prevention by interrupting transmission of Brugia malayi-microfilariae from cat reservoirs to humans via mosquitoes. The pharmacokinetics of ivermectin in eight healthy cats receiving a single subcutaneous dose of 0.2mg/kg was investigated. Jugular blood samples were collected periodically for up to 30days after dosing. The serum ivermectin concentrations were measured by high performance liquid chromatography with fluorescence detection. The pharmacokinetic parameters (mean+/-S.D.) derived from one-compartment model analysis were as follows: T(max) 1.22+/-0.49day, C(max) 16.75+/-4.04ng/mL, k(ab) 2.62+/-1.86day(-1), t(1/2)(ab) 0.27+/-0.25day, k(el) 0.27+/-0.14day(-1), t(1/2)(el) 2.53+/-2.24day, V(d)/F 9.81+/-5.41L/kg, Cl/F 2.21+/-0.69L/kg/day and AUC(0-->infinity) 98.31+/-30.52ngday/mL. In conclusion, the pharmacokinetics of ivermectin in cats receiving a single dose of 0.2mg/kg by subcutaneous injection revealed a rapid absorption, high distribution, slow elimination and high possibility for the elimination of B. malayi-microfilariae from currently endemic regions.