生长激素和胰岛素对猪卵母细胞体外成熟及孤雌胚卵裂的影响

本研究探讨了生长激素(STH)和胰岛素对猪卵母细胞体外成熟及孤雌激活后卵裂的影响。结果表明:在mNCSU-23液中,添加0.15μg/mLSTH组的成熟率(73.83%)和卵裂率(64.76%)显著高于对照组和添加0.01、0.05、0.1、0.2μg/mLSTH组(P<0.05);添加5μg/mL和8μg/mL胰岛素组的成熟率(66.25%、60.64%)显著高于添加0、0.5、2μg/mL及10μg/mL组(P<0.05);添加5μg/mL胰岛素组的卵裂率(61.63%)显著高于添加0、0.5、2、8、10μg/mL组(P<0.05);最佳的联合添加组为0.15μg/mLSTH+2μg/mL胰岛素,其体外成熟率为79.37%、卵裂率为72.31%。     

生长激素和胰岛素对猪卵母细胞体外成熟及电激活后卵裂的影响

研究了生长激素(somatotropin,STH)、胰岛素(Insulin)单独或者协同作用对猪卵母细胞成熟及电激活后卵裂的影响。结果表明,STH、Insulin对卵母细胞的成熟和激活后卵裂呈现双重效应。在NCSU-23基础液中添加0.15μg/mLSTH组的成熟率(73.83±1.80%)和卵裂率(64.76±2.54%)显著高于对照组及0.01、0.05、0.1、2.0μg/mLSTH组(P<0.05);添加5μg/mLInsulin的成熟率(65.05±1.34%)和8μg/mLInsulin组的成熟率(60.24±1.34%)显著高于对照组及0.5、2、10μg/mLInsulin组;添加5μg/mLInsulin组的卵裂率(61.33±2.62%)显著高于对照组及0.5、2、8、10μg/mLInsulin组(P<0.05);0.15μg/mLSTH与2μg/mLInsulin联合添加组成熟率和卵裂率最高,达到79.35±2.04%和72.31±1.19%,同其它组相比,差异显著(P<0.05),在本试验中为猪卵母细胞体外成熟的最佳条件。     

硒与酪氨酸对凌云乌鸡抗氧化功能、免疫球蛋白、酪氨酸酶活性和黑色素含量的影响

试验旨在通过探究硒与酪氨酸的添加水平对凌云乌鸡组织黑色素含量及其相关酶活性的影响,确定凌云乌鸡日粮中硒与酪氨酸的最适添加量,为利用营养元素调控凌云乌鸡药用价值提供参考依据。试验采用双因素交叉设计分组,日粮硒添加水平(0、0.2、0.3、0.4 mg/kg),酪氨酸添加水平(0、0.2%、0.4%、0.6%),选取13周龄体况良好、体重差异不显著的凌云乌鸡576只,随机分为16组,每组3个重复,每个重复12只鸡。基础日粮硒与酪氨酸含量为0.2 mg/kg和0.58%,饲养至20周龄末。试验结果表明:(1)日粮硒与酪氨酸水平对凌云乌鸡血清Ig M无显著影响(P0.05),第8组(0.2 mg/kg、0.2%)提高了血清中Ig A的浓度(P0.05),第10组(0.2 mg/kg、0.6%)使凌云乌鸡血清中Ig G浓度提高(P0.05)。(2)日粮硒与酪氨酸水平对凌云乌鸡酶活性研究结果表明,血清中第11组(0.3 mg/kg、0.2%)的谷胱甘肽过氧化物酶(GSH-Px)活性最高(P0.05),肌肉中第8组(0.2 mg/kg、0.2%)的GSH-Px活性最高(P0.05),肝脏中第10组(0.2 mg/kg、0.6%)的GSH-Px活性最高(P0.05),皮肤中第9组(0.2 mg/kg、0.4%)GSH-Px活性最高(P0.05)。血清中第15组(0.4 mg/kg、0.4%)的酪氨酸酶(TYR)活性最高(P0.05);皮肤中第12组(0.3 mg/kg、0.4%)的TYR活性最高(P0.05),硒与酪氨酸对血清、肝脏和皮肤中TYR活性存在互作效应(P0.05)。(3)对黑色素含量研究,肝脏中黑色素含量最高的组为第2组(0.2 mg/kg、0)(P0.05),肌肉中为第5组(0 mg/kg、0.2%)黑色素含量最高(P0.05),皮肤中为第9组(0.2 mg/kg、0.4%)黑色素含量最高(P0.05),硒与酪氨酸对肌肉、肝脏和皮肤中黑色素的含量存在互作效应(P0.05)。综上所述:日粮中适当添加硒与酪氨酸能提高血清与组织中黑色素含量、GSH-Px活性及TYR活性,当日粮硒与酪氨酸的水平为0.4 mg/kg和0.98%时,可以实现凌云乌鸡最佳药用价值。     

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。     

日粮中添加蛋氨酸锌对奶牛生产性能和相关生化指标的影响

选择12头中国荷斯坦奶牛随机分为4组,采用4×4拉丁方试验设计,A组为对照组(基础日粮),B、C和D组分别在A组基础上添加120、280和380 mg/kg蛋氨酸锌,研究其对奶牛生产性能和相关生化指标的影响。结果表明:B、C和D组的日均泌乳量分别比A组提高了1.28kg(5.65%)、1.59 kg(7.02%)和1.66 kg(7.33%),均差异显著(P<0.05);4%标准乳量分别提高了0.98 kg(4.73%)、1.22 kg(5.89%)和1.16 kg(5.60%),均达差异显著水平(P<0.05);乳脂率、乳糖、非脂乳固形物含量均差异不显著(P>0.05);乳蛋白分别提高了4.56%、7.02%和7.72%,均差异显著(P<0.05);乳锌含量分别提高了1.05μg/mL(36.59%)、1.59μg/mL(55.40%)和2.08μg/mL(72.47%),均差异极显著(P<0.01);体细胞数分别降低了1.64×104/mL(5.65%)、3.23×104/mL(11.12%)和3.89×104/mL(13.39%),均差异显著(P<0.05);平均干物质采食量分别提高了0.19 kg(0.98%)、0.29 kg(1.51%)和0.32 kg(1.66%),均差异不显著(P>0.05)。经济效益分析表明,C组每牛日均比A组增收3.42元,最为理想。     

鸡肉中喹乙醇、卡巴多及其代谢物的残留检测

建立了测定鸡肉组织样品中喹乙醇、卡巴多以及喹噁啉-2-羧酸残留量的高效液相色谱法。鸡肉样品中的药物用乙腈与乙酸乙酯的混合液(1∶1,V/V)提取,经过浓缩、净化,用甲醇定容进行检测。色谱拄为Atlantis C18柱,流动相由甲醇、水和乙酸钠缓冲液(pH 4.6)组成,采用梯度洗脱程序;检测波长为320和380 nm。喹乙醇、卡巴多及噁喹啉-2-羧酸在0.05~1.0μg/mL浓度范围内,药物峰面积与浓度值呈良好的线性关系,其相关系数分别为0.997 5、0.997 9、0.998 2。空白鸡肉中添加药物浓度为0.05、0.1、0.2和0.5μg/?时,喹乙醇的回收率为(70.6±3.1)%~(87.5±3.6)%;卡巴多为(73.2±3.7)%~(91.5±2.7)%;喹噁啉-2-羧酸为(71.9±4.3)%~(86.6±3.5)%。喹乙醇、卡巴多和喹噁啉-2-羧酸的最低检测限分别为0.05、0.015、0.025μg/mL。     

咖啡因对果蝇生物学效应的研究

为了探讨咖啡因对果蝇寿命、生育力和体重的影响,试验采用向培养基中添加咖啡因饲喂果蝇的方法对其进行研究。结果表明:在培养基中添加咖啡因能显著缩短果蝇平均寿命,与对照组相比,0.5,1.0,3.0 g/L浓度组雌果蝇平均寿命分别缩短了18.20%、51.35%、73.57%,雄果蝇平均寿命分别缩短了16.30%、58.96%、75.54%,差异均极显著(P<0.01);饲喂咖啡因后F1和F2代果蝇数量与对照组相比,分别下降了33.03%、71.04%、88.69%和49.05%、70.95%、90.71%,差异均极显著(P<0.01);试验组果蝇的平均体重均呈先上升后下降的趋势,但在饲喂咖啡因后,各试验组果蝇的平均体重比对照组下降快。     

泰地罗新注射液在猪体内的药代动力学及绝对生物利用度研究

为了研究泰地罗新注射液肌内注射和静脉注射在猪体内的药动学特征和绝对生物利用度,16只健康猪采用随机单剂量、平行试验设计,分别以4 mg/kg BW肌内注射和以1 mg/kg BW静脉注射泰地罗新注射液。采用超高效液相色谱-串联质谱法测定猪血浆中泰地罗新的浓度,以药动学分析软件WinNolin 6.4非房室模型计算药动学参数。结果显示,猪肌内注射泰地罗新注射液的药动学参数分别为Tmax(0.58±0.36)h,Cmax(0.88±0.17)μg/ml,AUClast(11.00±4.05)μg.h/mL,T1/2λz(33.58±22.01) h,MRTlast(35.60±10.00 )h。猪静脉注射泰地罗新注射液的药动学参数分别为AUClast(3.56±1.62)μg.h/mL,T1/2λz(50.91±23.47)h,MRTlast(37.53±4.52 )h,Vz(17.59±8.09)L/kg,Cl(0.31±0.14)L/h.kg。肌内注射泰地罗新注射液的绝对生物利用度77.15%,在猪体内的药动学特征是吸收迅速,血浆达峰时间短,消除半衰期长,绝对生物利用度高。     

不同浓度羧甲基壳聚糖对猪精液17℃保存效果的影响

为了探讨不同浓度的羧甲基壳聚糖(carboxymethyl chitin, CMCS)对猪精液常温保存效果的影响，试验采集了4头健康的2～3岁长白猪精液，利用未添加CMCS的Modena稀释液和添加不同浓度(30,50,70,100μg/mL)CMCS的Modena稀释液进行稀释，然后将稀释的猪精液在17℃环境中保存5 d,于保存第0(添加当天),1,3,5天测定精液精子活力、线粒体活性率、质膜完整率、精液pH值和渗透压指标，筛选CMCS的最佳添加浓度。结果表明：在常温保存过程中添加CMCS对猪精液具有保护作用，在精液保存第5天时，添加70μg/mL CMCS精液的精子活力、线粒体活性、质膜完整率最高，显著高于未添加和其他浓度(P<0.05);添加70μg/mL CMCS精液的渗透压最高，显著高于100μg/mL浓度(P<0.05),与未添加和30,50μg/mL浓度差异不显著(P>0.05);添加30,50,70μg/mL CMCS精液的pH值差异不显著(P>0.05),但均显著高于未添加和100μg/mL浓度(P<0.05)。说明CMCS在猪精液常温保...     

绵羊毛铅和血铅含量对铅中毒诊断意义的研究

绵羊15只,随机分成三个试验组。对照组不投铅,两个处理组分别以15和30mg铅/kg体重/天的剂量投服醋酸铅12周。投铅前1周及投铅后每周剪取试验组羊毛,同时于颈静脉采血,羊中毒死亡或投铅结束时扑杀采取组织,用无火焰原子吸收分光光度法分别测定毛铅、血铅及组织铅含量c对测定结果经统计分析表明,毛铅及血铅含量与累计投铅量、累计投铅大数及组织铅含量显著相关.从而证实羊毛铅和血铅含量可作为绵羊铅中毒诊断和环境铅污染监测的指标,并初步认为绵羊出现铅中毒症状,毛铅含量高于1.1PPm,或血铅含量高于0.16μg/ml时,可诊断为铅中毒。血铅含量与每kg体重投铅量显著相关,毛铅含量则与此相关不显著,血铅含量的波动较大,故认为毛铅含量较能准确地反映绵羊的铅状况,在绵羊慢性铅中毒诊断和环境污染的监测上,其意义较血铅为大,而血铅含量变化灵敏,对急性铅中毒诊断意义较大。此外,测定了非铅污染区60例正常绵羊毛铅、血铅及其中25例的肝和肾组织铅含量:毛0.249±0.026PPm(0.067～0.970),血0.070±00.001μg/ml(0.023～0.144),肾0.820±0.060PPm(0.100～1.410),肝l.074±0.054PPm(0.610～1.210)。 测定5例正常羊左右侧臂部、肩带部及胸侧壁的13个区域的毛铅含量,结果差异不显著。     

乌骨鸡日粮适宜苏氨酸水平的研究

采用单因素3水平试验设计研究了日粮苏氨酸水平对乌骨鸡各生长阶段生产性能的影响,结果表明:日粮中添加0.1%和0.15%苏氨酸乌骨鸡的体重、增重显著大于对照组和0.2%苏氨酸添加组(P<0.05)。     

Pharmacokinetics of enrofloxacin after intravenous,intramuscular and oral administration in houbara bustard (Chlamydotis undulata macqueenii)

The in-vitro activity of enrofloxacin against 117 strains of bacteria isolated from bustards was determined. Minimum inhibitory concentrations for 72% of the Proteus spp., E. coli, Salmonella spp. and Klebsiella spp. (n = 61) and for 48% of the Streptococci spp. and Staphylococci spp. (n = 31) were 0.5 μ g/mL. The minimum inhibitory concentration (MIC) of 76% of Pseudomonas spp. (n = 25) was 2 μg/mL. Fourteen strains were resistant to concentrations 128 μg/mL. The elimination half-lives (t½ elim β) (mean± SEM) of 10 mg/kg enrofloxacin in eight houbara bustards (Chlamydotis undulata) were 6.80± 0.79, 6.39± 1.49 and 5.63± 0.54 h after oral (p.o.), intramuscular (i.m.) and intravenous (i.v.) administration, respectively. Enrofloxacin was rapidly absorbed from the bustard gastro-intestinal tract and maximum plasma concentrations of 1.84± 0.16 μg/mL were achieved after 0.66± 0.05 h. Maximum plasma concentration after i.m. administration of 10 mg/kg was 2.75± 0.11 μg/mL at 1.72± 0.19 h. Maximum plasma concentration after i.m. administration of 15 mg/kg in two birds was 4.86 μg/mL. Bioavailability was 97.3± 13.7% and 62.7± 11.1% after i.m. and oral administration, respectively. Plasma concentrations of enrofloxacin 0.5 μg/mL were maintained for at least 12 h for all routes at 10 mg/kg and for 24 h after i.m. administration at 15 mg/kg. Plasma enrofloxacin concentrations were monitored during the first 3 days of treatment in five houbara bustards and kori bustards (Ardeotis kori) with bacterial infections receiving a single daily i.m. injection of 10 mg/kg for 3 days. The mean plasma enrofloxacin concentrations in the clinical cases at 27 and 51 h (3.69 and 3.86 μg/mL) and at 48 h (0.70 μg/mL) were significantly higher compared with the 3 h and 24 h time intervals from clinically normal birds. The maximum plasma concentration (C_max)/MIC ratio was ranked i.v. (10/mg/kg) > i.m. (15 mg/kg) > i.m. (10 mg/kg) > oral (10 mg/kg), but it was only higher than 8:1 for i.v and i.m. administrations of enrofloxacin at 10 mg/kg and 15 mg/kg, respectively, against a low MIC (0.5 μg/mL). A dosage regimen of 10 mg/kg repeated every 12 h, or 15 mg/kg repeated every 24 h, would be expected to give blood concentrations above 0.5 μg/mL and hence provide therapeutic response in the bustard against a wide range of bacterial infections.     

Estimated plasma bupivacaine concentration after single dose and eight-hour continuous intra-articular infusion of bupivacaine in normal dogs

Objective— To estimate maximum plasma concentration (C_max) and time to maximum plasma (t_max) bupivacaine concentration after intra‐articular administration of bupivacaine for single injection (SI) and injection followed by continuous infusion (CI) in normal dogs. Study Design— Cross‐over design with a 2‐week washout period. Animals— Healthy Coon Hound dogs (n=8). Methods— Using gas chromatography/mass spectrometry, canine plasma bupivacaine concentration was measured before and after SI (1.5 mg/kg) and CI (1.5 mg/kg and 0.3 mg/kg/h). Software was used to establish plasma concentration–time curves and estimate C_max, T_max and other pharmacokinetic variables for comparison of SI and CI. Results— Bupivacaine plasma concentration after SI and CI best fit a 3 exponential model. For SI, mean maximum concentration (C_max, 1.33±0.954 μg/mL) occurred at 11.37±4.546 minutes. For CI, mean C_max (1.13±0.509 μg/mL) occurred at 10.37±4.109 minutes. The area under the concentration–time curve was smaller for SI (143.59±118.390 μg/mL × min) than for CI (626.502±423.653 μg/mL × min, P=.02) and half‐life was shorter for SI (61.33±77.706 minutes) than for CI (245.363±104.415 minutes, P=.01). The highest plasma bupivacaine concentration for any dog was 3.2 μg/mL for SI and 2.3 μg/mL for CI. Conclusion— Intra‐articular bupivacaine administration results in delayed absorption from the stifle into the systemic circulation with mean C_max below that considered toxic and no systemic drug accumulation. Clinical Relevance— Intra‐articular bupivacaine can be administered with small risk of reaching toxic plasma concentrations in dogs, though toxic concentrations may be approached. Caution should be exercised with multimodal bupivacaine administration because plasma drug concentration may rise higher than with single intra‐articular injection.     

Bioavailability of spiramycin and lincomycin after oral administration to fed and fasted pigs

The disposition of spiramycin and lincomycin was measured after intravenous (i.v.) and oral (p.o.) administration to pigs. Twelve healthy pigs (six for each compound) weighing 16–43 kg received a dose of 10 mg/kg intravenously, and 55 mg/kg (spiramycin) or 33 mg/kg (lincomycin) orally in both a fasted and a fed condition in a three-way cross-over design. Spiramycin was detectable in plasma up to 30 h after intravenous and oral administration to both fasted and fed pigs, whereas lincomycin was detected for only 12 h after intravenous administration and up to 15 h after oral administration. The volume of distribution was 5.6 ± 1.5 and 1.1 ± 0.2 L/kg body weight for spiramycin and lincomycin, respectively. For both compounds the bioavailability was strongly dependent on the presence of food in the gastrointestinal tract. For spiramycin the bioavailability was determined to be 60% and 24% in fasted and fed pigs, respectively, whereas the corresponding figures for lincomycin were 73% and 41%. The maximum plasma concentration of spiramycin (C_max) was estimated to be 5 μg/mL in fasted pigs and 1 μg/mL only in fed pigs. It is concluded that an oral dose of 55 mg/kg body weight is not enough to give a therapeutically effective plasma concentration of spiramycin against species of Mycoplasma, Streptoccocus, Staphylococcus and Pasteurella multocida. The maximum plasma concentration of lincomycin was estimated to be 8 μg/mL in fasted pigs and 5 μg/mL in fed pigs, but as the minimum inhibitory concentration for lincomycin against Actinobacillus pleuropneumoniae and P. multocida is higher than 32 μg/mL a therapeutically effective plasma concentration could not be obtained following oral administration of the drug. For Mycoplasma the MIC₉₀ is below 1 μg/mL and a therapeutically effective plasma concentration of lincomycin was thus obtained after oral administration to both fed and fasted pigs.     

饲粮铜添加水平对泰和乌骨鸡生产性能和组织黑色素含量的影响

本试验旨在研究饲粮铜添加水平对 １～２８日龄泰和乌骨鸡生产性能和组织黑色素含量的影响。选用 １日龄泰和乌骨鸡 ２７０只,随机分成 ６组,每组设 ３个重复,每个重复 １５只鸡。试验鸡分别饲喂在基础饲粮（铜含量为 ４．７５ｍｇ／ｋｇ）中添加 ０、５、１５、３０、６０、１２５ｍｇ／ｋｇ铜的饲粮,饲养至 ２８日龄。结果表明：饲粮铜不同添加水平对 １～２８日龄泰和乌骨鸡平均日增重、平均日采食量和料重比均无显著影响（Ｐ＞０．０５）,但适量添加可显著或极显著影响其血清、肝脏、肾脏、皮肤及肌肉的黑色素含量、酪氨酸酶活性（Ｐ＜０．０５或 Ｐ＜０．０１）,并呈现出随饲粮铜添加水平的提高先升后降的趋势。当饲粮铜添加水平为 ３０ｍｇ／ｋｇ时,泰和乌骨鸡血清和组织酪氨酸酶活性及黑色素含量达到峰值。由此可知,玉米 －豆粕型基础饲粮中添加铜可提高泰和乌骨鸡组织黑色素含量,其适宜添加水平为 ３０ｍｇ／ｋｇ。     

商品代白羽乌骨鸡早期肉用性能的观测

对商品代白羽乌骨鸡早期肉用性能进行了观测，并以泰和鸡、黄羽乌骨鸡为对照组。结果表明：１０周龄体重，白羽乌骨鸡为１０３１．５ｇ、黄羽乌骨鸡为８５４．６ｇ、泰和鸡为５０３．０ｇ，三个鸡种间差异极显著。三个鸡种饲料转化比、屠宰率差异不显著。     

Pharmacokinetics and milk secretion of gabapentin and meloxicam co‐administered orally in Holstein‐Friesian cows

Malreddy, P. R., Coetzee, J. F., KuKanich, B., Gehring, R. Pharmacokinetics and milk secretion of gabapentin and meloxicam co‐administered orally in Holstein‐Friesian cows. J. vet. Pharmacol. Therap.  36 , 14–20. Management of neuropathic pain in dairy cattle could be achieved by combination therapy of gabapentin, a GABA analog and meloxicam, an nonsteroidal anti‐inflammatory drug. This study was designed to determine specifically the depletion of these drugs into milk. Six animals received meloxicam at 1 mg/kg and gabapentin at 10 mg/kg, while another group (n = 6) received meloxicam at 1 mg/kg and gabapentin at 20 mg/kg. Plasma and milk drug concentrations were determined over 7 days postadministration by HPLC/MS followed by noncompartmental pharmacokinetic analyses. The mean (±SD) plasma C_max and T_max for meloxicam (2.89 ± 0.48 μg/mL and 11.33 ± 4.12 h) were not much different from gabapentin at 10 mg/kg (2.87 ± 0.2 μg/mL and 8 ± 0 h). The mean (±SD) milk C_max for meloxicam (0.41 ± 80.16 μg/mL) was comparable to gabapentin at 10 mg/kg (0.63 ± 0.13 μg/mL and 12 ± 6.69 h). The mean plasma and milk C_max for gabapentin at 20 mg/kg P.O. were almost double the values at 10 mg/kg. The mean (±SD) milk to plasma ratio for meloxicam (0.14 ± 0.04) was lower than for gabapentin (0.23 ± 0.06). The results of this study suggest that milk from treated cows will have low drug residue concentration soon after plasma drug concentrations have fallen below effective levels.     

Pharmacokinetics and bone tissue concentrations of lincomycin following intravenous and intramuscular administrations to cats

Albarellos, G. A., Montoya, L., Denamiel, G. A. A., Velo, M. C., Landoni, M. F. Pharmacokinetics and bone tissue concentrations of lincomycin following intravenous and intramuscular administrations to cats. J. vet. Pharmacol. Therap.  35 , 534–540. The pharmacokinetic properties and bone concentrations of lincomycin in cats after single intravenous and intramuscular administrations at a dosage rate of 10 mg/kg were investigated. Lincomycin minimum inhibitory concentration (MIC) for some gram‐positive strains isolated from clinical cases was determined. Serum lincomycin disposition was best‐fitted to a bicompartmental and a monocompartmental open models with first‐order elimination after intravenous and intramuscular dosing, respectively. After intravenous administration, distribution was rapid (T_1/2(d) = 0.22 ± 0.09 h) and wide as reflected by the volume of distribution (V_(d(ss))) of 1.24 ± 0.08 L/kg. Plasma clearance was 0.28 ± 0.09 L/h·kg and elimination half‐life (T_1/2) 3.56 ± 0.62 h. Peak serum concentration (C_max), T_max, and bioavailability for the intramuscular administration were 7.97 ± 2.31 μg/mL, 0.12 ± 0.05 h, and 82.55 ± 23.64%, respectively. Thirty to 45 min after intravenous administration, lincomycin bone concentrations were 9.31 ± 1.75 μg/mL. At the same time after intramuscular administration, bone concentrations were 3.53 ± 0.28 μg/mL. The corresponding bone/serum ratios were 0.77 ± 0.04 (intravenous) and 0.69 ± 0.18 (intramuscular). Lincomycin MIC for Staphylococcus spp. ranged from 0.25 to 16 μg/mL and for Streptococcus spp. from 0.25 to 8 μg/mL.     

云南地区乌骨绵羊黑色素的初步研究

对7只兰坪乌骨绵羊、4只本地绵羊(非乌骨绵羊)和2羽乌骨鸡组织器官黑色素进行了测定,结果表明:乌骨绵羊黑色素与乌骨鸡黑色素的IR光谱基本一致,黑色物质主要是真黑色素;乌骨绵羊各组织器官中的黑色素含量高于本地绵羊;黑色素在乌骨绵羊组织器官中的沉积表现出明显的时(年龄)空(组织器官)差异,即随着年龄的增加,组织器官中的黑色素含量也随之增加;各组织器官中黑色素含量高低顺序为肝脏>气管、心脏、肾脏>脾脏、肺>舌、肌肉、皮肤>骨骼,与乌骨鸡的沉积模式有所不同;乌骨绵羊组织器官中黑色素含量与绵羊的毛色有关,黑毛绵羊组织器官黑色素含量高于花毛绵羊。     

Pharmacokinetic studies of flunixin meglumine and phenylbutazone in plasma,exudate and transudate in sheep

Flunixin meglumine (FM, 1.1 mg/kg) and phenylbutazone (PBZ, 4.4 mg/kg) were administered intravenously (i.v.) as a single dose to eight sheep prepared with subcutaneous (s.c.) tissue-cages in which an acute inflammatory reaction was stimulated with carrageenan. Pharmacokinetics of FM, PBZ and its active metabolite oxyphenbutazone (OPBZ) in plasma, exudate and transudate were investigated. Plasma kinetics showed that FM had an elimination half-life (t_½β) of 2.48 ± 0.12 h and an area under the concentration – time curve (AUC) of 30.61 ± 3.41 μg/mL.h. Elimination of PBZ from plasma was slow (t_½β = 17.92 ± 1.74 h, AUC = 968.04 ± μg/mL.h.). Both FM and PBZ distributed well into exudate and transudate although penetration was slow, indicated by maximal drug concentration (C_max) for FM of 1.82 ± 0.22 μg/mL at 5.50 ± 0.73 h (exudate) and 1.58 ± 0.30 μg/mL at 8.00 h (transudate), and C_max for PBZ of 22.32 ± 1.29 μg/mL at 9.50 ± 0.73 h (exudate) and 22.07 ± 1.57 μg/mL at 11.50 ± 1.92 h (transudate), and a high mean tissue-cage fluids:plasma AUC_last ratio obtained in the FM and PBZ groups (80–98%). These values are higher than previous reports in horses and calves using the same or higher dose rates. Elimination of FM and PBZ from exudate and transudate was slower than from plasma. Consequently the drug concentrations in plasma were initially higher and subsequently lower than in exudate and transudate.