气相色谱法测定肉桂油中桂皮醛的含量

目的:建立用气相色谱法测定肉桂油中桂皮醛的含量。方法:以OV-1弹性石英毛细管色谱柱(30m×0.25mm×0.25μm)为固定相,FID检测器,进样口温度230℃,检测器温度250℃,采用程序升温,柱温100℃,保持1min,然后以15℃/min的速率升至220℃,保持8min,载气为氮气,以正十八烷为内标,按内标法计算桂皮醛含量。结果:桂皮醛进样量在1.6~4.8mg/ml范围内其峰面积与进样量呈良好线性关系。y=0.1451x+0.1282,(r=0.9994);加样回收率为101.03%,RSD为0.53%(n=9)。结论该方法灵敏、简便,结果准确可靠,可作为控制肉桂油质量的方法。     

气相色谱法测定喉炎净散中龙脑的含量

建立气相色谱法测定喉炎净散中龙脑含量的方法。色谱柱：DB-WAX 30 m×0.25 mm×0.25μm,柱温：140℃,进样口温度：160℃,检测器温度：180℃,柱流量：1 mL/min,以氮气为载气,以乙酸乙酯为溶剂,以水杨酸甲酯为内标。龙脑进样量在0.1999~3.998μg时峰面积比与浓度呈良好的线性关系（R2=0.999）,平均回收率为99.1%,RSD为0.7%。该方法快速、灵敏、准确,可作为喉炎净散质量评价的依据。     

气相色谱外标法测定饲料添加剂丙二醇(包膜型)含量

为建立气相色谱外标法测定饲料添加剂丙二醇(包膜型)的含量,本研究采用中国科学院兰州化学物理研究所色谱中心PEG-20M毛细管色谱柱(30 m×0.25 mm×0.25μm);柱温150℃,保持6 min;进样口温度270℃;检测器温度280℃;检测器为火焰离子化检测仪(Flame Ionization Detector,FID);载气为氮气(N2);色谱柱流量1.5 mL/min;进样模式为分流进样;进样1μL,分流比为20:1进行测定。结果显示丙二醇在1 mg/mL～5 mg/mL的检测浓度范围内呈良好线性关系(r2=0.999 6),最低定量限为3.2μg。该方法操作简便、灵敏、准确,适用于饲料添加剂产品中丙二醇的含量控制。     

毛细管气相色谱法测定维生素E原料含量

用毛细管气相色谱法测定饲料添加剂维生素E原料中维生素E含量.以正三十二烷为内标物,采用DB-1毛细管柱(30 m×0.25 mm×0.25um),FID检测器;氮气为载气;柱温为280～290℃,检测器温度为290～300℃;进样口温度为290-300℃;无分流进样.在此色谱条件下,维生素E和内标物正三十二烷分离良好,在0.994～4.013 mg/mL浓度范围内呈良好线性关系,r=0.9998,经方法评估函数的评价表明,方法不存在恒定系统误差和相关性系统误差,方法准确性较好.本法操作简便易行,系统适用性良好,适用于饲料添加剂维生素E原料中维生素E含量测定.     

GC和RP-HPLC测定藏药石榴健胃片中桂皮醛含量的方法比较

目的:用GC和RP-HPLC对藏药石榴健胃片中桂皮醛进行含量测定,同时对2种方法进行比较。方法:GC采用Inter Cap WAX色谱柱,检测器FID,进样口温度200℃,分流模式进样,分流比10∶1;色谱柱流速1.0 mL/min(恒流模式);程序升温:初始温度150℃,保持4 min,以25℃/min速率升至230℃,持续3 min。RP-HPLC法采用Phenomenex Gemini C18色谱柱,流动相为乙腈-0.2%磷酸水溶液(48∶52);流速为1.0 mL/min;检测波长:289 nm;柱温:30℃。结果:GC法浓度在23.568~1 178.400μg/mL范围内线性关系良好,回归方程为A=440.689 4C-3 143.235,r=0.999 4,定量限为15.707μg/mL。RP-HPLC法浓度在0.591 1~35.466 0μg/mL范围内线性关系良好,回归方程为A=244 000C-51 500,r=0.999 9,定量限为0.0 047 388μg/mL。结论:GC和RP-HPLC均可用于藏药石榴健胃片中桂皮醛的含量测定。     

阿维菌素残留溶剂气相色谱检测方法的建立

采用6%氰丙基苯基-94%二甲基聚硅氧烷为固定相的毛细管柱,进样口温度220℃,检测器温度250℃,载气:氮气,流速5 m L/min,进样量0.2μL,分流比:10∶1,程序升温:初始温度为50℃,保持5 min,以每分钟15℃的速率升温至80℃,再以每分钟26.7℃的速率升温至240℃。在该色谱条件下,甲醇与内标异丙醇及溶剂间二甲苯分离度良好,检出限为6μg/m L,重复性RSD为3.0%,添加回收率为90.8%。不同色谱柱、柱温、流速、不同进样口温度、不同检测器温度耐用性良好。结果表明该方法可用于阿维菌素残留溶剂的定量检测。     

气相顶空法检测c-met抑制剂中异戊醇的残留

目的:用气相顶空外标法检测药物中的异戊醇残留。方法:将样品溶于N,N-二甲基咪唑啉酮,顶空90℃保持30 min,采用毛细管气相色谱柱HP-INNOWax(30 m×250μm×0.25μm);FID检测器;载气为氮气;流速3 mL/min;检测器温度250℃;进样口温度200℃;分流比5/1;程序升温:起始温度40℃,保持3 min,再以5℃/min温至90℃,保持5 min,最后以20℃/min升温至230℃,保持5 min。结果:异戊醇的线性范围为1.05~67.04μg/mL(R~2=0.998 2),定量限:1.05μg/mL,回收率为95.79%~98.78%,精密度1.0%,溶液稳定性符合设计要求。结论:所建立的气相顶空法灵敏准确、精密稳定,适合对药品中异戊醇的检测研究。     

气相色谱法测定"扑草净粉"中扑草净的含量

采用气相色谱法测定扑草净粉中扑草净的含量。采用3%PEG-20M玻璃填充柱(2m×6 mm),以三唑酮为内标物,FID检测器,载气为氮气,恒流流速40 mL/m in,柱温200℃,进样口、检测器220℃。在4.02~100.5μg/mL范围内线性良好,R2=0.999 6,理论塔板数为3 435,最低检测限为0.25μg/mL。该方法快速、灵敏、可靠,可用于扑草净粉的含量测定。     

响应面法优化渤海紫菜中脂肪酸的检测方法

研究紫菜中脂肪酸测定的前处理技术,样品经干燥,对超声提取条件采用响应面法进行优化,运用毛细管气相色谱法测定紫菜中重要脂肪酸的含量。结果表明,正己烷∶乙酸乙酯=13∶10、超声提取时间26 min、水浴温度60℃及水浴时间60 min粗脂肪百分含量最高;色谱条件:色谱柱为HP-88型毛细管柱(100 m×0.25 mm,0.2μm),柱温采用程序升温,载气为氮气,流速15 mL/min,FID检测器,温度为280℃,进样口温度260℃,分流比为10∶1,进样量为1μL。以保留时间定性,面积归一法定量,检测出紫菜中8种脂肪酸的含量。该方法操作简便、迅速、灵敏和准确度高,可满足紫菜中脂肪酸的检测需要。     

毛细管柱气相色谱法测定精制马拉硫磷溶液含量

建立了毛细管柱气相色谱法测定精制马拉硫磷溶液含量。采用5%苯基-95%甲基聚硅氧烷为固定相的毛细管柱,柱温230℃,进样口温度250℃,检测器温度265℃,载气:氮气;流速:2 mL/min;进样量1μL(分流比50∶1),内标物质为邻苯二甲酸二丙酯。在上述实验条件下,马拉硫磷峰与内标物质峰分离好(分离度10);马拉硫磷浓度在35.2～52.8 mg/mL范围内呈良好线性关系,r=0.9991;方法平均回收率为98.37%～100.08%,RSD为0.2%～0.3%(n=6);校正因子RSD为0.5%(n=6);供试品溶液在10 h内稳定。本法操作简便、快速、结果准确,应用于实际样品检测,结果满意,可作为精制马拉硫磷溶液含量测定的质控方法。     

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.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

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.     

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.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

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.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

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.     

Serum biochemical values and mineral element contents of tissues in yaks

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     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

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

Tropical Animal Health and Production -