超高效液相色谱串联质谱法检测貉子肉中氯霉素、氟甲砜霉素的残留量

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%。     

液相色谱-串联质谱法检测猪肉、鸡肉组织中维吉尼霉素M1残留量的研究

为了建立可同时检测猪肉、鸡肉组织中维吉尼霉素M_1药物残留的液相色谱-串联质谱分析方法,样品选用0.2%甲酸的乙腈/水(80∶20,V/V)溶液为提取液,经Oasis PRi ME HLB固相萃取小柱净化,在液相色谱-串联质谱仪上进行检测。结果表明,维吉尼霉素M_1在0.25~200 ng/m L浓度范围内呈现良好的线性关系,相关系数(R2)大于0.999。猪肉、鸡肉组织中维吉尼霉素M_1的检测限为0.5μg/kg,定量限为2.0μg/kg。在2~200μg/kg(2MRL)添加浓度水平上,回收率范围为80%~100%,批内、批间RSD均小于8.0%。该方法具有简便快捷、灵敏度高、定性准确等特点。     

超高效液相色谱-串联质谱法快速测定禽蛋中氯霉素、氟苯尼考及其代谢物残留

建立了快速测定禽蛋中氯霉素、氟苯尼考及氟苯尼考胺的超高效液相色谱-串联质谱分析方法。禽蛋用乙腈提取后,再用正己烷液液分配除脂,浓缩后用超高效液相色谱分离,以乙腈和10%甲醇水为流动相进行梯度洗脱,MRM反应监测模式检测。结果表明在5-200μg/L的系列浓度范围内均呈良好线性关系,相关系数均大于0.999。氯霉素、氟苯尼考、氟苯尼考胺的检测限为0.5μg/kg,定量限为2.0 μg/kg,本方法在2μg/kg～20μg/kg添加浓度范围内平均回收率为60%～100%,精密度小于20%。该方法方便快捷、定性准确适于禽蛋中的氯霉素、氟苯尼考及氟苯尼考胺药物残留检测。     

动物源食品中氯霉素、甲砜霉素、氟苯尼考及氟苯尼考胺残留检测－超高效液相色谱-串联质谱法研究

建立了动物源食品中氯霉素、甲砜霉素、氟苯尼考及氟苯尼考胺残留检测的超高效液相色谱-串联质谱（UPLC—MS／MS）分析方法。样品在碱性条件下用乙酸乙酯提取后,再用正己烷去除脂肪,浓缩后用BEH C18（50mm×2．1mm,1．7μm）色谱柱分离,以乙腈和水为流动相进行梯度洗脱,流速为0．3mL／min,多反应监测（MRM）模式检测。结果表明：四种药物在2—500μg／L的系列浓度范围内均呈良好线性关系,相关系数r均大于0．990。样品中氯霉素的检测限为0．1μg／kg,定量限为0．2μg/kg;甲砜霉素、氟苯尼考和氟苯尼考胺的检测限为0．5μg/kg,定量限为1μg／kg。本方法氯霉素在0．2～1μg／kg的添加浓度范围内,甲砜霉素、氟苯尼考及氟苯尼考胺在1—50μg／kg的添加浓度范围内平均回收率均为70％-120％,相对标准偏差（RSD）均小于20％。该方法具有简便快捷、灵敏度高、定性准确等特点。     

UPLC-MS／MS法同时测定鸡肉中的莫能菌素和盐霉素残留

建立了同时测定鸡肉中莫能菌素和盐霉素残留检测方法。在国内外已有研究的基础上,对样品前处理和仪器条件进行了改进,采用乙腈提取鸡肉中莫能菌素和盐霉素残留,石墨化碳黑SPE小柱对提取液进行净化,然后用Waters ACQUITY UPLCTMTQD超高效液相色谱-串联质谱仪测定。结果表明,莫能菌素和盐霉素的检测限为0.2μg/kg,最低定量限为0.5μg/kg。选取0.5、1.0、2.0μg/kg三个浓度进行空白添加回收率实验,回收率为71.9%~95.1%,批内变异系数和批间变异系数均小于15%,适合大量鸡肉样品中莫能菌素和盐霉素的残留检测。     

超高效液相色谱-串联质谱法检测动物源食品中氯霉素类药物及其代谢物残留

建立了动物源食品中氯霉素、甲砜霉素、氟苯尼考及氟苯尼考胺残留检测的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法.样品在碱性条件下用乙酸乙酯提取后,再用正己烷去除脂肪,浓缩后用BEH C18(50 mm×2.1 mm,1.7 μm)色谱柱分离,以乙腈和水为流动相进行梯度洗脱,流速为0.3 mL/min,多反应监测(MRM)模式检测.结果表明:四种药物在2～500 μg/L的系列浓度范围内均呈良好线性关系,相关系数r均大于0.990.样品中氯霉素的检测限为0.1 μg/kg,定量限为0.2 μg/kg;甲砜霉素、氟苯尼考和氟苯尼考胺的检测限为0.5 μg/kg,定量限为1 μg/kg.本方法氯霉素在0.2～1 μg/kg的添加浓度范围内,甲砜霉素、氟苯尼考及氟苯尼考胺在1～50 μg/kg的添加浓度范围内平均回收率均为70%～120%,相对标准偏差(RSD)均小于20%.该方法具有简便快捷、灵敏度高、定性准确等特点.     

加速溶剂萃取法结合超高效液相色谱-荧光法测定禽蛋中甲砜霉素残留

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。     

高效液相色谱-串联质谱法检测牛肌肉组织中加米霉素残留

建立一种测定牛肌肉组织中加米霉素残留的高效液相色谱-串联质谱方法。均质后的样品经0.1 mol/L磷酸二氢钾溶液提取,正己烷脱脂,HLB固相萃取柱净化,反相C 18色谱柱分离,采用多反应监测正离子模式测定。结果显示,该方法检测限为0.5μg/kg,定量限为2μg/kg;在2-400μg/kg范围内线性良好,相关系数r均大于0.999;平均回收率范围为91.6%-118.7%,批内变异系数在2.06%-11.06%之间（n=6）,批间变异系数在3.86%-7.98%之间（n=18）。该方法灵敏、准确、重复性好,适用于牛肌肉组织中加米霉素残留量的测定。     

超高效液相色谱-串联质谱法同时测定饲料中林可霉素和克林霉素残留

建立UPLC-MSMS法同时测定饲料中林可霉素和克林霉素残留量。样品处理采用乙腈提取,正己烷去除脂肪净化。分析采用"HSS T3色谱柱";流动相为0.1%(v/v)甲酸-水/乙腈溶液,梯度洗脱;正离子多反应监测模式;外标法进行定量。林可霉素的检出限为5.0μg/kg,定量限为20.0μg/kg,线性范围为20.0～400.0μg/L;克林霉素的检出限为1.0μg/kg,定量限为10.0μg/kg,线性范围分别为5.0～200.0μg/L。该方法专属性强、灵敏度高,分离度好,适用于饲料中林可霉素和克林霉素残留量的测定。     

饲料中甲砜霉素GC-MS检测方法的研究

用气相色谱-质谱法(GC-MS)测定饲料中甲砚霉素的含量,检测限为0.5μg/kg.通过色谱分离,保留时间与标准一致,选择离子相对丰度与标准均不大于20%,结果表明,该方法适用于饲料中的甲砜霉素含量测定.     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

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.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Changes in proportion of canine urinary calculi composed of calcium oxalate or struvite in specimens analyzed from 1981 through 2001

The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.     

Smart Phone Assisted City-scale Wireless Sensor Network Deployment for Transportation System Monitoring

<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

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.