妥曲珠利在鸡组织内的残留研究

研究鸡单剂量喂服(50 mg/kg·d,100mg/kg·d,连服2 d)妥曲珠利后在肝脏、肾脏、肌肉组织中的残留量,以便制定妥曲珠利预混剂的休药期.用乙腈-乙酸乙酯(3/2,v/v)提取组织中的药物,利用高效液相色谱法测定组织中妥曲珠利的浓度.试验结果表明,100mg/kg饲料添加妥曲珠利在鸡体内休药期为14 d,50 mg/kg时休药期为8 d.该结果与农业部制定的无公害食品饲养兽药使用准则中所规定的75～100 mg/kg鸡饮水妥曲珠利的休药期一致.     

鸡组织中地克珠利和妥曲珠利残留HPLC检测方法的建立

建立了同时检测鸡组织中地克珠利和妥曲珠利残留的高效液相色谱.经乙腈提取,正己烷脱脂,旋转蒸发浓缩后,以0.05mol/L磷酸/三乙胺(pH3.0):乙腈(40:60)作为流动相,反相高效液相色谱-紫外检测法检测,检测波长240 nm.鸡组织中地克珠利和妥曲珠利的回收率分别为92.0%～102.0%和83.4%～89.0%,变异系数为5.9%～12.2%,地克殊利和妥曲珠利的检测限分别为0.012 mg/kg和0.010 mg/kg,在0.05～1.0 mg/L质量浓度范围内呈良好的线性相关.该法样品处理简单,可同时检测地克珠利和妥曲珠利的残留,且准确度和精密度均符合残留分析的要求.     

妥曲珠利对肉鸡屠宰性能的影响及在肌肉中残留的研究

本试验旨在研究妥曲珠利对肉鸡屠宰性能的影响及其在肌肉中的残留。选取288只初生AA肉鸡,随机分4组,每组6个重复,饲喂相同基础日粮,对照组(1组)饮用常规自来水,试验组(2、3、4组)8¹0日龄饮水中分别添加25、50、100 mg/L妥曲珠利,试验期42 d。结果表明:妥曲珠利对肉鸡屠宰性能无显著影响(P>0.05),在肌肉中沉积的剂量效应显著(P<0.05);药物沉积量下降趋势符合指数函数模型,根据模型预测,2、3、4组胸肌中妥曲珠利分别于停药后3.42、4.74、5.73 d衰减到HPLC法最低检测限(74.45 ng/g)。综上所述,饮水中添加低于100 mg/L的妥曲珠利对肉鸡屠宰性能无影响,该药在肌肉中沉积的剂量效应显著。     

HPLC对妥曲珠利纳米乳中有效成分含量的检测

建立高效液相色谱法测定妥曲珠利纳米乳中妥曲珠利含量的方法。色谱柱为Agilent C18(4.6mm×150mm,5μm);流动相为磷酸二氢钾缓冲液(pH3):乙腈(45:55),流速1mL/min,紫外检测波长240nm,柱温30℃,进样量20μL。结果表明,妥曲珠利含量在0.0625μg/mL～100μg/mL范围内与峰面积呈良好的线性关系,检测限为5ng/mL,定量限为15ng/mL,平均加样回收率为99.73%。试验表明,该方法简便灵敏,结果准确可靠,可用于妥曲珠利纳米乳中妥曲珠利的质量控制。     

妥曲珠利对肉鸡生长性能和免疫机能的影响

本试验旨在研究饮水中添加不同水平妥曲珠利对肉鸡生长性能和免疫机能的影响.288只1日龄AA肉仔鸡,随机分为4组.各组日粮相同,对照组(1组)饮用自来水,试验组(2组、3组和4组)于8～10日龄连续3d饮水中分别添加妥曲珠利25mg/L、50 mg/L和100 mg/L,试验期42 d.结果表明,妥曲珠利对肉鸡生长性能和血清新城疫抗体效价均无显著影响(P＞0.05);25mg/L和50 mg/L妥曲珠利组肉鸡28日龄胸腺指数和脾脏指数显著高于对照组(P＜0.05),100mg/L妥曲珠利组肉鸡28日龄腔上囊指数显著低于对照组(P＜0.05);50 mg/L妥曲珠利组外周血T淋巴细胞的转化率显著高于对照组(P＜0.05).可见,饮水中添加25 mg/L和50 mg/L妥曲珠利对肉鸡免疫机能有一定促进作用.     

建立一种基于超高效液相色谱-串联质谱测定猪肉中地克珠利和妥曲珠利残留的方法

本文建立了一种检测猪肉中地克珠利和妥曲珠利残留的超高效液相色谱-串联质谱方法。地克珠利和妥曲珠利在10.0μg/kg～500.0μg/kg线性范围内,标准曲线的相关系数(r)均大于0.996,呈现良好的线性关系。地克珠利和妥曲珠利的检出限分别为1.22μg/kg和1.25μg/kg,在加标回收试验中的回收率范围分别为81.4%～105.0%和86.0%～103.0%,相对标准偏差范围为3.8%～6.2%。试验结果表明,该方法简单、快速、准确,且检出限低、回收率高,能适用于猪肉中地克珠利和妥曲珠利残留的检测。     

曲妥珠单抗的高效液相色谱定量分析

本文采用高效液相色谱法以磷酸盐缓冲液为流动相,凝胶柱和紫外检测器定量分析曲妥珠单抗注射液中曲妥珠单抗的药物含量。结果表明曲妥珠单抗注射液浓度在10μg/m L~1mg/m L范围内浓度与紫外吸收峰面积呈良好的线性关系,线性相关系数r≥0.99。     

动物用抗球虫新药妥曲珠利

概述动物用三嗪酮类抗球虫新药妥曲珠利（toltrazuril)的研究进展。包括其杀虫活性、作用机理、毒性及临床应用。该药具有活性强、毒性低等特点。     

妥曲珠利抗鸡球虫病药效实验

鸡球虫病是由艾美耳球虫引起的鸡寄生虫病,15-30日龄的雏鸡发病率高达80%以上,死亡率高达30%.在各种鸡病中球虫病的发生率最高,占15%～20%[1],是目前对养鸡业危害最大的一种寄生虫病.据Bhogai(1992)报道,全世界每年因鸡球虫病造成的损失达20亿美元.由于规模化集约化养鸡场的饲养条件特别适合球虫卵囊孢子化发育,而且卵囊仅对热敏感,对常用消毒药有很强的抵抗力[2],所以很难用卫生管理手段防止鸡球虫病的发生,因此,药物防治仍是防止该病的主要措施.十九世纪七十年代以来,先后合成并生产了许多不同类型杀灭球虫的药物,但是都因鸡球虫耐药虫株的不断产生而大大降低了药效.因此,寻求高效、低毒、不易产生耐药性的抗球虫新药的开发研制已迫在眉捷.     

高效毛细管电泳法同时检测地克珠利和妥曲珠利的含量

采用毛细管电泳-二极管阵列检测法建立了地克珠利和妥曲珠利两种结构相近的均三嗪类抗球虫药物的分离检测方法.同时还探讨了缓冲溶液的种类、浓度、pH值等诸多因素对分离检测结果的影响.上述两种药物在8 min内实现了基线分离.线性检测范围为0.5～100 μg/mL,检出限为0.1 μg/mL (S/N=3).     

恩诺沙星在肉鸡组织中残留消除规律研究

选择250只1日龄"AA"肉鸡,喂养至35日龄开始在饮水中添加75 mg/L恩诺沙星,自由饮水,连续用药5日后休药.休药0时,肉鸡胸肌、肝脏、脂肪和肾脏中恩诺沙星含量分别为1 381.62、2 247.20、219.45、1 616.81μg/kg.休药48 h后,肉鸡组织中未检出恩诺沙星.结果表明农业部规定恩诺沙星在肉鸡中的休药期为8日是科学合理的.     

磺胺对甲氧嘧啶在肉鸡组织中的残留研究

将艾维茵肉鸡100羽随机分成4组,在基础日粮中分别添加不同水平的磺胺对甲氧嘧啶(从第Ⅰ到第Ⅳ组分别添加0、500、1000、2000mg/kg),连喂3d后停药,并于停药后第1、2、3、5、10d时每组各捕杀鸡10只,迅速取出肝脏、肾脏、肌肉组织,用高效液相色谱法测定这些组织中磺胺对甲氧嘧啶的残留。结果表明,停药后10d内,肌肉、肝脏和肾脏中均有浓度不一的残留,其检测限达0.005mg/kg,回收率在87%以上。     

恩诺沙星在猪组织中残留消除规律研究

在常规饲养条件下,对健康猪按2.5 mg/kg体重的剂量肌肉注射2.5%恩诺沙星注射液,每日2次,连续注射3 d.停药后第2、4、6、8、10、12、14天分别屠宰4头猪.分别采取每头猪的肌肉(注射部位)、脂肪(腹脂)、肝和肾脏等4种组织,用高效液相色谱法进行残留量测定.结果表明:残留在肌肉、脂肪组织中的药物消除较快,第8天总残留量(恩诺沙星 环丙沙星)已下降至检测限(20μg/kg)以下;肝和肾脏组织中的药物消除缓慢,第14天测得猪肾中药物总残留量为40μg/kg.     

盐酸沃尼妙林预混剂在猪组织中残留消除规律研究

建立了猪肝脏、肾脏、肌肉和脂肪中盐酸沃尼妙林的高效液相色谱检测方法并研究盐酸沃尼妙林预混剂在猪体内各组织中的残留消除规律。对24头健康猪以200mg/kg的剂量混饲给药21d。在停药后0、6、12、18、24、36h分别宰杀4头猪,采集各组织进行药物残留测定。方法的检测限为0.025～0.062 5μg/g,定量限为0.05～0.1μg/g,肝脏的平均回收率为75.5%～76.4%,变异系数为2.3%～3.8%;肾脏的平均回收率为75.8%～78.5%,变异系数为4.1%～6.0%;肌肉的平均回收率为79.3%～80.0%,变异系数为3.0%～4.7%;脂肪的平均回收率为76.7%～77.3%,变异系数为3.3%～5.4%。结果表明,盐酸沃尼妙林在肝脏中残留量最高,肾脏其次;肌肉和脂肪中的残留量显著低于肝脏和肾脏,停药24h时,残留量低于定量限;停药36h时残留量均低至检测限以下。盐酸沃尼妙林预混剂在猪组织中消除迅速,建议休药期为2d。     

Determination of sulphachloropyrazine-diaveridine residues by high performance liquid chromatography in broiler edible tissues

Diaveridine (DVD) is used in combination with sulphachloropyrazine (SPZ) as an effective antibacterial agent and antiprotozoal agent, respectively, in humans and animals. To gain a better understanding of the metabolism of SPZ and DVD in the food-producing animals, a high performance liquid chromatography (HPLC) method to determine and quantify sulphachloropyrazine (SPZ) and diaveridine (DVD) suspension residues from broilers is reported. Thirty healthy chickens were orally administered with sulphachloropyrazine-diaveridine (SPZ-DVD) suspension in water of 300 mg/l (SPZ) per day for seven successive days. Six chickens per day were slaughtered at 0, 1, 3, 5 and 7 days after the last administration. This procedure permitted SPZ and DVD to be separated from muscle tissue, liver, kidneys and skin with fat after extraction with acetonitrile and acetone under slightly acidic conditions. From the detected residuals in different tissues, we found that SPZ was quickly eliminated in liver and muscle, and slowly eliminated in kidney and skin with fat. DVD was quickly eliminated in liver and slowly eliminated in kidney. The withdrawal period of SPZ was 3.26, 3.72, 4.39 and 5.43 days in muscle, liver, kidney and skin with fat, respectively. The withdrawal period of DVD was 4.77, 4.94, 6.74 and 4.58 days in muscle, liver, kidney and skin with fat, respectively. Therefore, the suggested withdrawal period for SPZ-DVD suspension should be 7 days after dosing for seven successive days.     

Dioxin residues in the edible tissue of broiler chicken

The aim of this study was to determine the contamination of broiler chicken with polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) after feeding either uncontaminated feed or feed contaminated with 1, 2 or 4 ng/kg toxic equivalents (TEQ). The feed was mixed with pure substances of PCDD/Fs to get the intended contamination. Ten groups of seven 1-day-old chickens each were housed in special cages for broiler fattening. The fattening period lasted for 6 weeks. The contaminated feed was given for either 2, 4, or 6 weeks, one group received uncontaminated feed (control group). After slaughtering the edible parts of the chickens breast and leg including the skin were homogenized. Body weight gain and feed conversion (kg feed/kg body weight gain) were in the normal range (final weight 1.98+/-0.07 kg; feed conversion 1.74+/-0.03). One kilogram edible tissue contained an average of 21.2+/-4.1% of the total TEQ-intake in all groups. The PCDD/Fs residues in the edible tissues significantly correlated with the amount of PCDD/Fs-intake (r=0.99; Pearson correlation). There was no decrease in dioxin residues (% of total PCDD/Fs intake) after a 2 or 4 weeks withdrawal period. The results of this trial predict that a threshold value of 2 pg/g chicken fat can be met if the PCDD/Fs content in chicken feed is not higher than 0.4 ng/kg.     

Transfer of nitrofuran residues from parent broiler breeder chickens to broiler progeny

The use of nitrofuran antibiotics in food-producing animals is prohibited within the EU. Countries in the EU, as well those intending to export food to the EU, must ensure that their products are free from nitrofuran residues. As a result of recent global problems where chicken meat from a wide range of countries has been contaminated with nitrofuran metabolites, an investigation was performed to discover whether or not residues of the nitrofurans might be transferred from parent breeder chickens to their offspring broilers. Four groups of broiler breeders were each treated with one of the nitrofurans: furazolidone, nitrofurazone, nitrofurantoin or furaltadone. Residues of their side-chain metabolites, AOZ, SEM, AHD and AMOZ, were detected in the fertilised eggs at concentrations up to 1567 microg/kg. However, in the chicks that subsequently hatched from these eggs, residue concentrations of SEM, for example, were only found up to 26.6 and 32.5 microg/kg in liver and muscle, respectively, for 1-d-old chicks. Residue concentrations in tissues had fallen below the detection limit of the analytical method for 40-d-old broiler chicks, for all compounds except for semicarbazide (SEM, the nitrofurazone metabolite). Relatively high concentrations of nitrofurans are available to the newly hatched chick through the egg yolk. However, most of these residues are neither utilised nor deposited in the liver or muscle.