牛皮下注射爱普菌素注射剂后组织残留休药期的建立

建立牛肌肉、肝脏、肾脏和脂肪组织中爱普菌素残留的高效液相色谱荧光检测方法（HPLC-FLD）,并用统计学方法计算牛皮下注射爱普菌素后组织残留的休药期。牛组织样品经乙腈提取,过碱性SPE柱。组织样品添加浓度为2～100 ng·g^-1,平均回收率为70.5%～91.2%,变异系数为2.3%～11.5%;方法检测限和定量限分别为1和2 ng·g^-1。18头牛颈部皮下一次性注射爱普菌素注射液（1%）,注射剂量为200μg.kg-1体质量,分别在给药后第1、3、7、14、21、28天各屠宰3头取样,经HPLC-FLD分析。结果表明,皮下单次注射给药后,肌肉中药物残留量（2.1～9.3 ng·g^-1）低于美国规定的残留限量（10 ng·g^-1）;肝脏中药物残留量（29.8～625.1 ng·g^-1）低于美国、欧盟和CAC规定的残留限量（分别为4 800、1 500和2 000 ng·g^-1）;肾脏和脂肪中药物残留量（4.1～112.5ng·g^-1和2.1～96.4 ng·g^-1）都低于欧盟和CAC规定的残留限量（300和250 ng·g^-1）。采用欧盟官方推荐方法对残留浓度-时间数据统计分析,牛肌肉、肝脏、肾脏、脂肪休药期均为0 d。     

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。     

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。     

牦牛主要寄生虫病高效低残留防治技术研究(下)

为制定埃普利诺菌素(EPR)休药期及建立牦牛主要寄生虫病高效低残留防治技术提供科学依据。采用荧光高效液相色谱法(HPLC-FLD)检测埃普利诺菌素(EPR)浇泼剂在牦牛组织中的残留消除规律。结果:给牦牛按推荐剂量0.5mg.kg~(-1)给予EPR浇泼剂后,EPR在牦牛体内分布广泛,牦牛组织中EPR于2d达到最高浓度,之后浓度逐渐下降,药物浓度由高至低依次为肝脏、肾脏、脂肪、肌肉组织,浇泼部位肌肉与后腿肌肉药物残留量无差异,肝脏是EPR作用的靶组织,检出药物浓度由高到低分别为肝脏1050.50ng.g~(-1)、肾脏139.47ng.g~(-1)、脂肪20.76ng.g~(-1)、血浆10.24ng.g~(-1)、后腿肌肉5.63ng.g~(-1)、背部肌肉5.00ng.g~(-1)。第9d组织中残留量为肝脏505.12ng.g~(-1),肾脏66.23ng.g~(-1),脂肪14.87ng.g~(-1),血浆4.09ng.g~(-1),肌肉2.41～2.47ng.g~(-1)。略低于欧盟(EU)、国际食品法典委员会(CAC)规定的标准。研究结果表明,EPR浇泼剂0.5mg.kg~(-1)推荐剂量用于泌乳牦牛无需弃奶期,牦牛肉用时无需休药期或建议休药期为1d。为建立牦牛主要寄生虫病高效低残留防治技术提供了依据。     

庆大霉素在羊体内代谢和残留消除规律研究

为研究庆大霉素在羊体内代谢和残留消除规律,以4 mg/kg肌肉注射硫酸庆大霉素注射液,每日2次,代谢研究连续注射2.5 d,残留消除研究连续注射3 d。按动物试验要求采集肌肉、肝脏、肾脏、脂肪、血液、尿液和粪便,UPLC-MS/MS法测定样品中庆大霉素的残留量。结果显示,庆大霉素在羊体内1 h可到血药峰浓度,尿液中的排泄总量占注射总量的80%左右,粪便中不足0.1%;在肝脏、肾脏、尿液中原型药总量占注射总量90%以上,证明庆大霉素在羊体内不代谢,原型药随尿液排出体外;庆大霉素在肾脏中残留浓度最高且消除时间长,确定肾脏是庆大霉素在羊体内的靶组织,庆大霉素原型药为残留标示物。研究结果可为庆大霉素的安全使用以及正确制订其在羊组织中的最高残留限量标准提供科学依据和建议。     

长效盐酸多西环素注射液在猪体内残留的消除规律

在常规饲养条件下,对35头健康成年猪按10 mg/kg体质量的剂量肌肉注射10%长效盐酸多西环素注射液,给药2次,给药间隔时间为48 h。第2次给药后12 h及2、5、9、14、192、5 d分别屠宰5头猪,分别采取每头猪的肌肉、肝脏、肾脏、皮肤+脂肪和注射位点肌肉等5种组织,用高效液相色谱法进行残留量测定。结果表明:在第2次给药后19 d,多西环素在各组织均能检测到,且残留均低于残留限量。多西环素残留浓度大小顺序:注射部位(肾脏(肝脏(皮脂(肌肉。采用WT1.4软件制定的统计方法来处理猪组织中药物浓度-时间数据,以制定休药期。     

恩诺沙星注射液在猪体内的残留消除研究

为研究恩诺沙星在猪体内的残留消除规律,验证休药期,以2.5 mg/kg体重肌内注射10%恩诺沙星注射液,每日2次,连续3 d。在最后一次给药后0、3、5、7、10 d时间点,采集肌肉、肝脏、肾脏、脂肪和注射部位肌肉,HPLC法测定组织中的恩诺沙星及其代谢物环丙沙星的残留量,并用WT1.4软件计算休药期。结果显示,恩诺沙星在猪肌肉、肝脏、肾脏、脂肪和注射部位肌肉的休药期分别是5.6、13.4、8.2、3.0、5.5 d。为保证兽药使用安全、消费者健康和食品安全,推荐恩诺沙星注射液在猪的休药期为14 d。     

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%。     

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。     

喹乙醇及其主要代谢物在罗非鱼体内的药物动力学研究

采用高效液相色谱-质谱法,研究肌肉注射给药方式下,喹乙醇及其代谢物在罗非鱼(Tilapiafish)体内的药物代谢动力学.罗非鱼注射给药20 mg/kg后,其血浆、肌肉、肝脏中药物浓度-时间曲线关系符合一级吸收的二室开放动力学模型.喹乙醇在罗非鱼体内消除较快,在血液、肌肉、肝脏中的消除半衰期(t 1/2β)分别为5.2...     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

獭兔睾丸的组织学观察

家兔作为一种实验动物 ,推动了繁殖技术的发展。本试验通过对不同年龄公獭兔的睾丸进行组织学观察、测定 ,研究精子的发生规律 ,为系统地进行繁殖生理工作提供依据。1　材料与方法选 60日龄、75日龄、90日龄 3个年龄公獭兔各5只 ,用外科手术法摘取两侧睾丸 ,放入 Bouin氏液中固定 ,二甲苯透明 ,石蜡包埋 ,切成 5～ 8μm切片 ,H.E.染色。在显微镜下观察 ,并进行定量组织学指标测定及差异性比较。2　结果和讨论2 .1　睾丸定量组织学指标的测定结果　见表 1。表 1　獭兔睾丸定量组织学指标　　　μm,个 /精细管60日龄 75日龄 90日龄曲细精管…     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Observations of fracture of the anconeal process of the ulna of swine

Fractures of the anconeal process of 5 pigs ranging in age from 4 to 8 months were studied radiographically and histologically. Clinically, animals with a fracture of the anconeal process had a "tight," restricted gait. In pigs at 4.5 months of age, a radiolucent line through the base of the anconeal process was composed of fibrocartilage, fibrous connective tissue, and hyaline cartilage. Subperiosteal proliferation of woven bone was located along the cranial surface of the olecranon, adjacent to the base of the anconeal process. In older animals, the radiolucent line through the anconeal process contained variable amounts of fibrous connective tissue and fibrocartilage. The proliferation of subperiosteal bone at the base of the anconeal process formed a "buttress callus" which retained a radiolucent area between the callus and the proximal surface of the anconeal process. The latter region of radiolucency was continuous with the transversely oriented line that traversed the base of the anconeal process.     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.