盐酸克伦特罗在羊主要脏器中残留量消除规律的研究

本试验对盐酸克伦特罗在休药期肉羊眼睛、心脏、肾脏、肺脏、脾脏等组织中的残留规律进行了研究。选择24头体重为(30±5)kg健康肉羊进行试验,在饲料中添加50 μg/kg盐酸克伦特罗,连续饲喂35 d后休药,通过液相色谱—质谱联用/质谱检测休药期肉羊组织中克伦特罗含量,研究其残留量消除规律。试验结果表明,肉羊眼睛中有高浓度的盐酸克伦特罗残留且其在肝脏中消除较慢;停药第14天眼睛中盐酸克伦特罗的浓度仍为42.42～63.48 μg/kg,脾脏中盐酸克伦特罗消除速度是最快的;停药3 d时,检测不到盐酸克伦特罗的残留量(低于检出限0.07 μg/kg),故眼睛可用作检测盐酸克伦特罗在肉羊生产上非法使用的靶标。     

气相色谱-串联质谱法测定饲料中的瘦肉精

盐酸克伦特罗也称为"瘦肉精",可作为一种主要的β-兴奋剂应用于畜禽肉制品生产中,用以提高肌肉和脂肪的比例并加快生长速度。在畜禽产品中过量残留会对消费者造成危害,因此在畜禽养殖中被禁止使用。盐酸克伦特罗在家畜与人体内易吸收,而且与其它β-兴奋剂相比,它的利用率更高,以致食用了含有盐酸克伦特罗的猪肉出现中毒现象。由于盐酸克伦特罗会残留在动物的肌肉与内脏组织中,对饲料中盐酸克伦特罗进行监测也就显得尤为重要。经试验,应用GC-MS法检测饲料中盐酸克伦特罗,标准曲线r值≥0.99999;变异系数(CV值)≤0.91%;检测回收率:88.2%～98.2%;回收率标准偏差≤1.47%。     

气相色谱串联质谱法检测饲料中的盐酸克伦特罗

盐酸克伦特罗作为一种主要的β-兴奋剂应用于畜禽肉制品生产中,用以提高肌肉和脂肪的比例并加快生长速度。在畜禽产品中过量残留会对消费者造成危害,因此被禁止在畜禽养殖中使用。盐酸克伦特罗在家畜与人体内吸收好,而且与其他β-兴奋相比,它的利用率高,以至食用了含有盐酸克伦特罗的猪肉出现中毒现象。由于盐酸克伦特罗通过饲料对动物的饲喂会残留在动物的肌肉与内脏组织中,对饲料中盐酸克伦特罗进行监测也就显得尤为重要。经试验,应用气相色谱串联质谱法检测饲料中盐酸克伦特罗,标准曲线r≥0.99999;变异系数(CV值)≤0.91%;检测回收率88.2%～98.2%;回收率标准偏差≤1.47%。     

应用气质联用法检测饲料中盐酸克伦特罗的探讨

盐酸克伦特罗作为一种主要的β-兴奋剂应用于畜禽肉制品生产中,用以提高肌肉和脂肪的比例并加快生长速度。在畜禽产品中过量残留会对消费者造成危害,因此被禁止在畜禽养殖中使用。盐酸克伦特罗在家畜与人体内吸收好,而且与其他β-兴奋剂相比,它的利用率高,以致于食用了含有盐酸克伦特罗的猪肉出现中毒现象。由于盐酸克伦特罗易残留在动物的肌肉与内脏组织中,对饲料中盐酸克伦特罗进行监测显得尤为重要。经试验,应用GC-MS法检测饲料中盐酸克伦特罗,标准曲线r值≥0.99999;变异系数(CV值)≤0.91%;检测回收率:88.2%~98.2%;回收率标准偏差≤1.47%。     

北京地区盐酸克伦特罗残留控制情况监测

盐酸克伦特罗是我国明令禁止使用的兽药之一,人食用含有盐酸克伦特罗药物残留的动物组织后,会产生严重的毒副作用,严重者可导致死亡.在我国,盐酸克伦特罗主要被非法用于养猪生产,含有盐酸克伦特罗的猪产品时刻威胁着人民的身体健康.从2000年-20008年期间,对北京市大型超市、集贸市场、批发市场、养猪场、屠宰场和饲料场随机抽取的动物组织、尿液、饲料和饮用水进行了盐酸克伦特罗残留检测,结果显示北京市盐酸克伦特罗残留水平呈明显的逐年下降趋势,这说明北京市盐酸克伦特罗的非法使用现象得到了有效控制.     

盐酸克伦特罗的残留危害及检测方法

介绍了盐酸克伦特罗的理化特性及药用机制,分析了盐酸克伦特罗的残留对动物和人体造成的危害,同时总结了国内外盐酸克伦特罗残留的检测方法。     

警惕β-兴奋剂“改头换面”堪害消费者

盐酸克伦特罗(俗称瘦肉精)是β-兴奋剂的一种。β-兴奋剂在人类医学上常见还有沙丁胺醇、马布特罗等。自从有人证实盐酸克伦特罗具有减少胴体脂肪，提高瘦肉率，使瘦肉外观鲜艳等特点。目前，我国对盐酸克伦特罗的查处力度较大，但在实际检测中发现盐酸克伦特罗的检出率极低，而在猪尿检时却有很高的阳性率。不法分子为了对付检测查处，     

谨防盐酸克伦特罗中毒

近一时期以来 ,有关吃含有“瘦肉精”猪肉的中毒事件时有发生 ,“瘦肉精”是一种饲料添加剂 ,其主要成分含有盐酸克伦特罗。盐酸克伦特罗是克伦特罗的盐酸盐 ,克伦特罗通用Ｃｌｅｎ -ｂｕｔｅｒｏｌ的译音又称氨哮素、克喘素 ,化学名称为羟甲叔丁肾上腺素。盐酸克伦特罗是白色或类臼色的结晶粉末 ,无臭 ,昧苦。由于本品化学性质稳定 ,加热到 172℃时才分解 ,因此一般加热方法不能将其破坏 ,该药物可选择性地作用于肾上腺素 β2受体 ,是一种强效激动剂。当人食用了含盐酸克伦特罗的肉以后 ,盐酸克伦特罗进入体内主要分布于肝脏 ,在肝脏中去甲…     

饲料中β-受体激动剂的检测研究进展

1β-受体激动剂的基本知识β-受体激动剂是一类化学合成的苯乙醇胺类衍生物,20世纪80年代至今,人工合成β-兴奋剂主要有盐酸克伦特罗、莱克多巴胺、沙丁胺醇、西马特罗和班布特罗等十多种。1.1盐酸克仑特罗盐酸克伦特罗,英文名Clenbuteral(CLB),中文名瘦肉精、克伦特罗、盐酸克伦特罗、盐酸双氯     

浅谈动物源性食品中盐酸克伦特罗的残留及危害

简要介绍了盐酸克伦特罗的理化性质、作用机理及残留特性,阐述了动物源性食品中盐酸克伦特罗残留物对动物及人体的危害。     

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。     

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。     

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.