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《中国畜牧杂志》2020,(6)
本研究以鸡蛋、鸭蛋、鹅蛋为样本基质,建立一种加速溶剂萃取法结合超高效液相色谱-荧光法(UPLC-FLD)测定禽蛋中甲砜霉素残留。样品通过液-液萃取或加速溶剂萃取方法进行提取,乙腈饱和的正己烷去脂,复溶后利用液相色谱柱进行等度洗脱分离,而后采用荧光检测器进行定量。结果显示:甲砜霉素在空白禽蛋样品中的添加浓度在检测限(Limit of Detection,LOD)-250.0μg/kg范围内,相关系数均大于0.999 5,回收率为82.9%～95.3%,相对标准偏差均低于4.0%。检测限为3.3～3.4μg/kg,定量限为9.7～9.9μg/kg。综上,液-液萃取和加速溶剂萃取法均能很好地提取禽蛋样品中甲砜霉素,同时该检测方法高效、快速,适用于检测禽蛋中甲砜霉素残留。 相似文献
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高效液相色谱荧光检测法检测鸡肉中甲砜霉素残留 总被引：1，自引：1，他引：0
研究建立了用高效液相色谱荧光法检测鸡肉中甲砜霉素残留的方法。鸡肉经丙酮、二氯甲烷提取,饱和正己烷脱脂,氮吹仪吹干浓缩后,以乙腈―磷酸二氢钠溶液（0.01 mol/L,含0.005 mol/L十二烷基硫酸钠和0.1%三乙胺)（32∶68,V/V）为流动相,流速为1.0 mL/min,荧光检测激发波长为225 nm,发射波长为290 nm。甲砜霉素在0.01～1.75 mg/L浓度范围内,本方法线性关系良好,相关系数为0.9991。当甲砜霉素添加水平为5～500 μg/kg时,该方法平均回收率为79.49%～89.71%,相对标准偏差为4.96%～9.61%;日内相对标准偏差为5.68%～7.47%;日间相对标准偏差为8.89%～11.32%。甲砜霉素检测限为1.5 μg/kg（S/N＝3）,定量限5 μg/kg（S/N＝10）。所建立的方法简便、快速、灵敏度高,适用于鸡肉中甲砜霉素残留的高灵敏度检测。 相似文献
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高效液相色谱法测定饲料中甲砜霉素含量 总被引：1，自引：0，他引：1
建立了测定饲料中甲砜霉素的含量的高效液相色谱检测方法。2g饲料样品,乙酸乙酯提取后蒸干,加入4%氯化钠,正己烷脱脂后乙酸乙酯反提,蒸干,流动相溶解后上机。色谱柱为C18,流动相为甲醇-水(25:75,V/V),检测波长225nm,流速1.2mL/min,柱温室温。在0.1～500μg/mL的质量浓度内甲砜霉素的峰面积与质量浓度呈良好的线性关系(r=0.9997),平均回收率超过76%,RSD小于12%。 相似文献
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建立了用高效液相色谱荧光检测法检测鸡蛋中甲砜霉素残留量的方法。样品经碱性乙酸乙酯提取,饱和正己烷脱脂,氮吹仪吹干浓缩后,以乙腈-磷酸二氢钠溶液（0.01mol/L,含0.005mol/L L十二烷基硫酸钠和0.1%三乙胺）（35∶65）为流动相,流速为1.0mL/min,荧光检测激发波长为224nm,发射波长为290nm。甲砜霉素在0.025～5.0mg/L质量浓度范围内,本方法线性关系良好,相关系数为0.999 7。当甲砜霉素添加水平为15～500μg/kg时,该方法平均回收率为86.35%～93.76%,相对标准偏差为4.21%～7.89%,日内相对标准偏差为4.84%～6.62%;日间相对标准偏差为8.92%～10.83%。甲砜霉素最低检测限为1.5μg/kg（S/N=3）,最低定量限5μg/kg（S/N=10）。所建立的方法简便、快速、灵敏度高,适用于鸡蛋中甲砜霉素残留的高灵敏度检测。 相似文献
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用高效液相色谱法测定甲砜霉素含量,色谱柱用C18(5μm,4.6mm×150mm),柱温为室温,流动相为乙腈-水(46),检测波长225nm,流速1.0nfl/min,进样量20μl.方法的线形范围为0.025～0.2mg/ml,r=0.9990. 相似文献
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甲砜霉素在鸡肌肉中的残留消除规律 总被引：1，自引：0，他引：1
为研究甲砜霉素在鸡肌肉中的残留消除规律,鸡肌肉样品经丙酮、二氯甲烷提取,饱和正己烷脱脂,氮吹仪吹干浓缩后用流动相溶解,上高效液相色谱荧光检测器检测。测定鸡肌肉样品中甲砜霉素的检测限为1.5μg.kg-1(S/N=3)、定量限为5μg.kg-1(S/N=10)。各试验组鸡分别按体质量以10.0、20.0和50.0mg.(kg.d)-1剂量给药,每天1次,连续5d内服给药后,鸡肉中甲砜霉素残留量随给药剂量增大呈上升趋势,随休药期的延长而降低。休药第1天时,鸡肉中甲砜霉素残留量均达到峰值。休药前期甲砜霉素残留消除较快,后期消除缓慢。休药第5天时,鸡肉中甲砜霉素残留量均低于50μg.kg-1,休药第9天时,鸡肌肉中甲砜霉素残留量均低于检测限(1.5μg.kg-1);甲砜霉素在鸡肌肉中的残留量与给药剂量呈正相关。 相似文献
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[目的]研究羊奶粉中氯霉素、甲砜霉素、氟甲砜霉素残留的液相色谱-串联质谱测定方法。[方法]样品经乙腈提取,固相萃取柱净化,以甲醇水作为流动相,采用多反应监测负离子模式进行定性及内标法定量分析。[结果]氯霉素、甲砜霉素、氟甲砜霉素的相关系数均大于0.999,氯霉素检出限为0.1μg/kg,甲砜霉素和氟甲砜霉素检出限为0.2μg/kg;氯霉素加标回收率为100.9%～116.2%,甲砜霉素加标回收率为88.4%～99.6%,氟甲砜霉素加标回收率为89.6%～103.2%。[结论]该方法灵敏度高、准确性好,适于测定羊奶粉中氯霉素、甲砜霉素,氟甲砜霉素的残留量。 相似文献
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《养殖与饲料．饲料世界》2019,(8)
本研究建立了一种针对貉子肉中氯霉素、氟甲砜霉素的超高效液相色谱串联质谱的检测方法。以氘代氯霉素(D5-CAP)为内标,样品经乙腈提取,乙腈饱和正己烷除脂,固相萃取柱净化后,采用多反应监测(MRM)负离子模式,对貉子肉中氯霉素、氟甲砜霉素的残留量进行定量检测。结果表明,2种药物在0.1～5.0μg/mL范围内均呈现良好线性关系,相关系数r均大于0.999。样品中氯霉素和氟甲砜霉素的检测限为0.1μg/kg,定量限为0.3μg/kg,本方法在0.5～2.0μg/kg添加范围内药物回收率为68%～115%,其相对偏差均小于10%。 相似文献
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液相色谱-荧光检测法检测水产品中甲砜霉素、氟甲砜霉素及代谢物氟甲砜霉素胺残留 总被引：2，自引：0，他引：2
建立了以带荧光检测器的液相色谱检测水产品中甲砜霉素、氟甲砜霉素与氟甲砜霉素胺残留的新方法.采用碱性乙酸乙酯-乙腈提取试样中残留的化合物,凝胶渗透色谱(GPC)净化,荧光检测器的激发与发射波长分别为225 nm与295 nm,可疑样品以液相色谱-质谱/质谱进行确证.在添加浓度为0.050～2.0 mg/kg时,平均回收率在86.4%～96.8%之间,相对标准偏差(RSD)在5.63%～9.71%之间(n=5);甲砜霉素、氟甲砜霉素在0.20～5.0 mg/L范围内、氟甲砜霉素胺在0.10～5.0 mg/L范围内有良好的线性关系,甲砜霉素与氟甲砜霉素的检测限达0.020mg/kg、氟甲砜霉素胺的检测限达0.010 mg/kg. 相似文献
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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。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
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。 相似文献
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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. 相似文献
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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. 相似文献
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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。 相似文献
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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. 相似文献