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1.
建立了分散固相萃取结合液相色谱串联质谱法检测牛肉、牛脂肪、牛肝和牛肾等可食性组织中的泰地罗新残留量的方法。取牛组织样品经50%(V/V)乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,正己烷脱脂,高速离心分层后,取适量乙腈层溶液经0.1%(V/V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000 r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为0.1%甲酸和乙腈溶液,采用梯度程序进行洗脱,三重四级杆质谱进行定性定量分析。结果表明,方法的最低检测限为5μg/kg,最低定量限为10μg/kg,添加含量在10～1000μg/kg范围内线性关系良好(r0.995),对应添加回收率为60%～110%,RSD10%,表明该方法具有较好的准确度与精密度。  相似文献   

2.
建立了检测鸡肉、鸡皮脂、鸡肝和鸡蛋中泰万菌素以及其主要代谢产物3-乙酰泰乐菌素残留量的液相色谱串联质谱检测方法。前处理使用分散固相萃取法,选择使用50%(v/v)乙腈提取,无水MgSO4进行脱水和盐析,正己烷脱脂,酸性氧化铝粉末进行样品净化。将离心后的上清液以如下方法进行上机检测：使用反相色谱柱进行分离,流动相为0.1 %甲酸和乙腈,采用梯度程序进行洗脱,三重四级杆质谱进行定性定量分析。实验结果表明,方法的最低检出限为2.5 μg/kg,最低定量限为5 μg/kg,在5～200 μg/kg范围内线性关系良好(r >0.995),添加回收率在60 %～110 ％,RSD＜20 ％,表明该方法具有较好的准确度与精密度。  相似文献   

3.
建立了检测生鲜牛乳及奶粉中双氰胺的亲水作用色谱-电喷雾串联质谱(HILIC-ESI-MS/MS)分析方法.样品经乙腈提取后经亲水作用色谱柱分离,电喷雾串联四级杆质谱检测.结果显示,双氰胺标准曲线在0.5～100μg/L浓度范围内线性良好.相关系数(r)大于0.99;在5～50μg/kg添加水平下,回收率在80.1％～88.2％之间,相对标准偏差(RSD)均小于10％(n=6);方法操作简便、灵敏度高,适用于生鲜牛乳及奶粉中双氰胺的筛查及确证分析.  相似文献   

4.
建立超高效液相色谱-串联质谱测定牛羊可食性组织中巴氯芬残留量的分析方法。取均质后的动物组织经80%(V/V)乙腈甲酸溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,高速离心分层后合并提取液,取适量乙腈层溶液经prime HLB直过式固相萃取柱净化后,以40℃氮气吹干。残渣以15%乙腈甲酸溶液复溶后以反相C18为固定相,0.1%甲酸与0.1%甲酸乙腈为流动相,采用梯度洗脱程序进行分离,以串联质谱进行同位素内标法定性定量分析。巴氯芬在0.5～50μg/kg范围内线性关系良好(r=0.9994),方法的最低检出限为0.25μg/kg,最低定量限为0.50μg/kg,添加回收率在89.09%～109.52%内,批内批间变异系数(CV)小于10%。该方法具有较好的准确度与精密度,适用于牛羊可食性组织中巴氯芬残留量的测定。  相似文献   

5.
本研究建立了鸡肉组织中氯丙嗪残留检测的高效液相色谱-串联质谱(HPLC-MS/MS)定量确证方法。建立的方法所用样品用酸化乙腈和乙腈饱和正己烷提取后,采用C18柱色谱分离,正离子扫描模式,分别以乙腈和5 mmol/L乙酸铵水溶液(含0.1%甲酸)、乙腈和水为流动相,梯度洗脱,电喷雾电离,多反应监测模式检测,内标法定量。该方法检测限为0.008μg/kg,定量限为0.025μg/kg,在0.025~2.5μg/kg的添加范围内,回收率为71.5%~86.7%,日内、日间变异系数均小于7.6%。  相似文献   

6.
饲料中安定的残留分析   总被引：1，自引：0，他引：1  
本实验建立了饲料中安定的液相色谱-质谱联用(LC-MS)检测方法。液相色谱条件为分析柱WatersSunfireTMC18150mm×2.1mm,3.5μm,流动相为乙腈-0.2%甲酸(体积比55∶45),流速:0.2mL/min。质谱条件为电喷雾离子源(ESI ),选择离子监测(SIR)质荷比(m/z)为285,228,154带正电荷的准分子离子和碎片离子。在此条件下安定的线性范围为1～1000μg/L,方法最低定量检测限为1.0μg/kg,安定的回收率为75%±10%。  相似文献   

7.
为了检测猪组织中泰地罗新残留量,试验采用70%乙腈提取,HLB固相萃取柱净化,以乙腈和0.1%甲酸水溶液为流动相,经BEH C_(18)色谱柱梯度洗脱,电喷雾正离子扫描和多反应监测模式对泰地罗新进行质谱分析,建立了超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。结果表明:在25～1 000μg/kg范围内,泰地罗新特征离子质谱响应值与质量浓度呈良好的线性关系,相关系数为0.999;检测限在4.5～7.5μg/kg,定量限15.0～25.0μg/kg;加标回收率为90.5%～98.3%,相对标准偏差为0.5%～3.7%。说明该法准确度高、回收率好,适用于猪组织中泰地罗新残留量的测定。  相似文献   

8.
研究建立了检测鸡肉组织中氨苯砜的高效液相色谱串联质谱(HPLC-MS/MS)定量确证方法。样品采用1%乙酸-乙腈(v/v)提取,乙腈饱和正己烷脱脂,采用C18反相色谱柱分离,以乙腈和5 mmol/L乙酸铵水溶液(含0.1%甲酸)为流动相,梯度洗脱,电喷雾电离,正离子-多反应监测扫描模式,氨苯砜的定量、定性离子分别为249.1156.0,249.1108.0。建立的方法在0.05~10μg/kg范围内线性良好,检测限为0.015μg/kg,定量限为0.05μg/kg,在0.05~5μg/kg的添加范围内,回收率在76.2%~94.5%之间,日内、日间变异系数均小于19.4%。  相似文献   

9.
建立了超高效液相色谱-静电轨道阱质谱联用测定禽蛋中五氯苯酚残留量的分析方法。取均质后的禽蛋样品经乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,高速离心分层后,取适量乙腈层溶液经0.1%(V∶V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000 r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为乙腈:0.1%甲酸=75∶25,采用等度程序进行洗脱,静电轨道阱质谱进行定性定量分析。结果表明,五氯苯酚在0.5~100μg/kg范围内线性关系良好(r>0.995),方法的最低检出限为0.2μg/kg,最低定量限为0.5μg/kg,添加回收率在74.43%~96.85%之间,批内批间变异系数CV%<10%。该方法具有较好的准确度与精密度,适用于禽蛋中五氯苯酚残留量的测定。  相似文献   

10.
吴剑平  严凤  张婧  王博  黄士新  曹莹  张晶 《中国饲料》2023,(13):106-112
为建立超高效液相色谱-串联质谱测定水产饲料中乙撑脲(EU)和乙撑硫脲(ETU)残留量的分析方法,取均质后的水产饲料样品经1%(V/V)氨水乙腈溶液提取,加入氯化钠和无水硫酸镁进行脱水和盐析,高速离心分层后,取适量乙腈层溶液经0.1%(V:V)甲酸稀释后,用20 mg季铵盐(PSA)进行样品净化并以10000 r/min离心取上清液,使用石墨化炭黑柱进行分离,流动相为0.1%甲酸与0.1%甲酸乙腈,采用梯度程序进行洗脱,串联质谱进行定量分析。结果表明:乙撑脲和乙撑硫脲在10～1000μg/kg内线性关系良好(r>0.995),方法的最低检出限为5μg/kg,最低定量限为10μg/kg,添加回收率为77.66%～106.31%,批内批间变异系数CV<10%。该方法具有较好的准确度与精密度,适用于水产饲料中二硫代甲酸酯类农药所引入的乙撑脲和乙撑硫脲残留量的测定。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

13.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

14.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

15.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
  相似文献   

16.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

17.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

18.
A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.  相似文献   

20.
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